10-Q

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 10-Q

(Mark One)
ý	QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended September 30, 2007
OR
o	TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                             to

Commission File No. 33-7591

(An Electric Membership Corporation)
(Exact name of registrant as specified in its charter)

Georgia (State or other jurisdiction of incorporation or organization)	58-1211925 (I.R.S. employer identification no.)
2100 East Exchange Place Tucker, Georgia (Address of principal executive offices)	30084 (Zip Code)
Registrant's telephone number, including area code	(770) 270-7600

        Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

        Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of "accelerated filer" and "large accelerated filer" in Rule 12b-2 of the Exchange Act. (Check one): Large Accelerated Filer o    Accelerated Filer o    Non-Accelerated Filer ý

        Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o    No ý

        Indicate the number of shares outstanding of each of the registrant's classes of common stock, as of the latest practicable date. The registrant is a membership corporation and has no authorized or outstanding equity securities.

OGLETHORPE POWER CORPORATION
INDEX TO QUARTERLY REPORT ON FORM 10-Q
FOR THE QUARTER ENDED SEPTEMBER 30, 2007

			Page No.
PART I — FINANCIAL INFORMATION
	Item 1.	Financial Statements
		Unaudited Condensed Balance Sheets as of September 30, 2007 and December 31, 2006	2
		Unaudited Condensed Statements of Revenues and Expenses For the Three Months and Nine Months ended September 30, 2007 and 2006	4
		Unaudited Condensed Statements of Patronage Capital and Membership Fees and Accumulated Other Comprehensive Deficit For the Nine Months ended September 30, 2007 and 2006	5
		Condensed Statements of Cash Flows Unaudited For the Nine Months ended September 30, 2007 and 2006	6
		Notes to Unaudited Condensed Financial Statements For the Nine Months ended September 30, 2007 and 2006	7
	Item 2.	Management's Discussion and Analysis of Financial Condition and Results of Operations	11
	Item 3.	Quantitative and Qualitative Disclosures About Market Risk	17
	Item 4.	Controls and Procedures	17
PART II — OTHER INFORMATION
	Item 1.	Legal Proceedings	19
	Item 1A.	Risk Factors	19
	Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	19
	Item 3.	Defaults Upon Senior Securities	19
	Item 4.	Submission of Matters to a Vote of Security Holders	19
	Item 5.	Other Information	19
	Item 6.	Exhibits	19
SIGNATURES			20

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PART I—FINANCIAL INFORMATION
Item 1. Financial Statements

Oglethorpe Power Corporation
Condensed Balance Sheets
September 30, 2007 and December 31, 2006

			(dollars in thousands)
		2007			2006
			(Unaudited)
Assets
Electric plant:
	In service	$	5,785,438		$	5,769,129
	Less: Accumulated provision for depreciation		(2,594,690	)		(2,495,049	)
			3,190,748			3,274,080
	Nuclear fuel, at amortized cost		117,252			119,076
	Construction work in progress		139,535			68,145
			3,447,535			3,461,301
Investments and funds:
	Decommissioning fund, at market		248,635			233,309
	Deposit on Rocky Mountain transactions, at cost		99,621			94,772
	Bond, reserve and construction funds, at market		5,524			6,397
	Investment in associated companies, at cost		45,506			43,331
	Long-term investments, at market		103,306			118,281
	Other, at cost		1,477			1,478
			504,069			497,568
Current assets:
	Cash and cash equivalents, at cost		326,320			423,757
	Restricted cash and cash equivalents, at cost		—			18,312
	Receivables		122,620			91,360
	Inventories, at average cost		139,537			135,996
	Prepayments and other current assets		4,034			4,234
			592,511			673,659
Deferred charges:
	Premium and loss on reacquired debt, being amortized		106,652			112,147
	Deferred amortization of capital leases		92,272			95,450
	Deferred debt expense, being amortized		30,052			30,072
	Deferred outage costs, being amortized		30,311			25,782
	Deferred tax assets		72,000			—
	Other		8,133			5,766
			339,420			269,217
		$	4,883,535		$	4,901,745

The accompanying notes are an integral part of these condensed financial statements.

2

Oglethorpe Power Corporation
Condensed Balance Sheets
September 30, 2007 and December 31, 2006

			(dollars in thousands)
		2007			2006
			(Unaudited)
Equity and Liabilities
Capitalization:
	Patronage capital and membership fees	$	516,404		$	497,509
	Accumulated other comprehensive deficit		(29,214	)		(28,988	)
			487,190			468,521
	Long-term debt		3,212,853			3,197,478
	Obligation under capital leases		257,321			283,816
	Obligation under Rocky Mountain transactions		99,621			94,772
			4,056,985			4,044,587
Current liabilities:
	Long-term debt and capital leases due within one year		121,572			234,621
	Accounts payable		29,393			31,662
	Accrued interest		43,473			54,489
	Accrued and withheld taxes		44,428			41,755
	Other current liabilities		9,179			9,167
			248,045			371,694
Deferred credits and other liabilities:
	Gain on sale of plant, being amortized		36,629			38,485
	Net benefit of Rocky Mountain transactions, being amortized		61,318			63,707
	Asset retirement obligations		261,558			249,575
	Accumulated retirement costs for other obligations		54,708			56,220
	Deferred liability associated with retirement obligations		18,420			11,085
	Interest rate swap arrangements		29,088			29,417
	Long-term contingent liability		72,000			—
	Other		44,784			36,975
			578,505			485,464
		$	4,883,535		$	4,901,745

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Oglethorpe Power Corporation
Condensed Statements of Revenues and Expenses (Unaudited)
For the Three and Nine Months Ended September 30, 2007 and 2006

				(dollars in thousands)
			Three Months						Nine Months
			2007			2006			2007			2006
Operating revenues:
	Sales to Members		$	345,519		$	330,294		$	915,890		$	874,773
	Sales to non-Members			506			312			1,252			1,084
		Total operating revenues		346,025			330,606			917,142			875,857
Operating expenses:
	Fuel			139,918			129,992			327,136			289,356
	Production			71,270			64,888			200,143			189,793
	Purchased power			50,726			53,381			121,882			146,907
	Depreciation and amortization			36,646			36,376			109,640			120,866
	Accretion			3,294			2,176			13,456			14,147
	Gain on sale of emission allowances			—			—			(394	)		(39,529	)
		Total operating expenses		301,854			286,813			771,863			721,540
Operating margin				44,171			43,793			145,279			154,317
Other income (expense):
	Investment income			9,468			6,763			32,762			29,415
	Other			1,871			1,990			6,654			6,491
		Total other income		11,339			8,753			39,416			35,906
Interest charges:
	Interest on long-term debt and capital leases			52,634			50,137			157,495			149,924
	Other interest			303			772			1,525			2,282
	Allowance for debt funds used during construction			(2,013	)		(1,042	)		(5,036	)		(2,272	)
	Amortization of debt discount and expense			3,500			3,939			11,816			11,819
		Net interest charges		54,424			53,806			165,800			161,753
Net margin			$	1,086		$	(1,260	)	$	18,895		$	28,470

4

Oglethorpe Power Corporation
Condensed Statements of Patronage Capital and Membership Fees
and Accumulated Other Comprehensive Deficit (Unaudited)
For the Nine Months Ended September 30, 2007 and 2006

			(dollars in thousands)
		Patronage Capital and Membership Fees		Accumulated Other Comprehensive Deficit			Total
Balance at December 31, 2005		$	479,308	$	(35,498	)	$	443,810
Components of comprehensive margin:
	Net margin		28,470					28,470
	Unrealized gain on interest rate swap arrangements				4,799			4,799
	Unrealized gain on available-for-sale securities				126			126
Total comprehensive margin								33,395
Balance at September 30, 2006		$	507,778	$	(30,573	)	$	477,205
Balance at December 31, 2006		$	497,509	$	(28,988	)	$	468,521
Components of comprehensive margin:
	Net margin		18,895					18,895
	Unrealized loss on interest rate swap arrangements				(504	)		(504	)
	Unrealized gain on available-for-sale securities				278			278
Total comprehensive margin								18,669
Balance at September 30, 2007		$	516,404	$	(29,214	)	$	487,190

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Oglethorpe Power Corporation
Condensed Statements of Cash Flows (Unaudited)
For the Nine Months Ended September 30, 2007 and 2006

					(dollars in thousands)
				2007			2006
Cash flows from operating activities:
	Net margin			$	18,895		$	28,470
	Adjustments to reconcile net margin to net cash provided by operating activities:
		Depreciation and amortization, including nuclear fuel			175,916			177,089
		Accretion cost			13,456			14,147
		Amortization of deferred gains associated with sale-leasebacks			(4,245	)		(4,245	)
		Allowance for equity funds used during construction			(1,283	)		(597	)
		Deferred outage costs			(28,075	)		(24,777	)
		Other			1,873			725
	Change in operating assets and liabilities:
		Receivables			(32,826	)		(5,039	)
		Inventories			(3,541	)		(37,390	)
		Prepayments and other current assets			200			325
		Accounts payable			(2,268	)		(25,270	)
		Accrued interest			(11,017	)		(8,710	)
		Accrued and withheld taxes			2,673			9,861
		Other current liabilities			797			(352	)
			Total adjustments		111,660			95,767
Net cash provided by operating activities					130,555			124,237
Cash flows from investing activities:
	Property additions				(123,106	)		(71,868	)
	Activity in decommissioning fund—Purchases				(417,577	)		(613,238	)
	—Proceeds				404,963			599,218
	Activity in bond, reserve and construction funds—Purchases				(137	)		(176	)
	—Proceeds				1,100			1,178
	Decrease in restricted cash and cash equivalents				18,312			16,156
	Decrease inother short-term investments				—			182,218
	Increase in investment in associated organizations				(1,669	)		(1,987	)
	Activity in other long-term investments—Purchases				(493,015	)		(299,748	)
	—Proceeds				510,964			263,994
	Increase in Members' advances				—			(74,471	)
	Other				(1,879	)		1,128
Net cash (used in) provided by investing activities					(102,044	)		2,404
Cash flows from financing activities:
	Long-term debt proceeds				26,389			—
	Long-term debt payments				(150,559	)		(136,048	)
	Other debt related costs				(1,778	)		625
Net cash used in financing activities					(125,948	)		(135,423	)
Net decrease in cash and cash equivalents					(97,437	)		(8,782	)
Cash and cash equivalents at beginning of period					423,757			170,734
Cash and cash equivalents at end of period				$	326,320		$	161,952
Cash paid for:
	Interest (net of amounts capitalized)			$	165,000		$	158,644

6

Oglethorpe Power Corporation
Notes to Unaudited Condensed Financial Statements
September 30, 2007 and 2006

(A)

General.    The condensed financial statements included in this report have been prepared by Oglethorpe Power Corporation (Oglethorpe), pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). In the opinion of management, the information furnished in this report reflects all adjustments (which include only normal recurring adjustments) and estimates necessary to fairly state, in all material respects, the results for the periods ended September 30, 2007 and 2006. Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles have been condensed or omitted pursuant to SEC rules and regulations, although Oglethorpe believes that the disclosures are adequate to make the information presented not misleading. These condensed financial statements should be read in conjunction with the financial statements and the notes thereto included in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006, as filed with the SEC. The results of operations for the three-month and nine-month periods ended September 30, 2007 are not necessarily indicative of results to be expected for the full year. As noted in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006, substantially all of Oglethorpe's sales are to its 38 electric distribution cooperative members (the Members) and, thus, the receivables on the accompanying balance sheets are principally from its Members. (See "Notes to Financial Statements" in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006.)

(B)

Adoption of Financial Interpretation No. 48, "Accounting for Uncertainty in Income Taxes—an Interpretation of Financial Accounting Standards No. 109 Positions" (FIN 48).    In July 2006, the Financial Accounting Standards Board (FASB) issued FIN 48. The interpretation addresses the determination of whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the financial statements. Under FIN 48, Oglethorpe may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such a position should be measured based on the largest benefit that has the greater than fifty percent likelihood of being realized upon ultimate settlement. FIN 48 also provides guidance on derecognition, classification, interest and penalties on income taxes, accounting in interim periods and requires increased disclosures.

Oglethorpe and its subsidiaries file a U.S. federal consolidated income tax return. The U.S. federal statute of limitations remains open for the year 2004 forward. State jurisdictions have statutes of limitations generally ranging from three to five years from the filing of an income tax return. The state impact of any federal changes remains subject to examination by various states for a period of up to one year after formal notification to the states. Years still open to examination by tax authorities in major state jurisdictions include 2004 forward.

Oglethorpe adopted the provisions of FIN 48 effective January 1, 2007. As a result of the adoption of FIN 48, Oglethorpe recognized a $96 million increase in the liability for unrecognized tax benefits. This change in the liability resulted in no decrease to the January 1, 2007 balance of patronage capital as the effects were offset by recognition of deferred tax assets. During the third quarter of 2007, one of the four open years expired. Accordingly, this liability and related deferred tax asset was reduced by $24 million during the third quarter. Oglethorpe is carrying forward significant regular tax and alternative minimum tax (AMT) net operating losses (NOLs). Therefore, any regular tax liability in the open years related to the uncertain tax position would be offset by regular NOLs. However, Oglethorpe would be liable for the portion of AMT for this

7

period that is not allowed to be offset by the AMT NOLs. In the current open years, Oglethorpe's exposure is not material to its consolidated results of operations, cash flows or financial position.

Oglethorpe recognizes accrued interest with uncertain tax positions in interest expense in the condensed statements of revenues and expenses. As of September 30, 2007, Oglethorpe has recorded approximately $464,450 for interest in the accompanying balance sheet. It is expected that the amount of unrecognized tax benefits will change in the next twelve months; however, Oglethorpe does not expect the change to have a significant impact on its results of operations, its financial position or its effective tax rate.

(C)

New Accounting Standards.    In February 2007, the FASB issued SFAS No. 159, "The Fair Value Option for Financial Assets and Financial Liabilities," including an amendment of SFAS No. 115, "Accounting for Certain Investments in Debt and Equity Securities." This statement permits entities to choose to measure many financial instruments and certain other items at fair value that are not currently required to be measured at fair value. This statement also establishes presentation and disclosure requirements designed to facilitate comparison between entities that choose different measurement attributes for similar types of assets and liabilities. The statement provides entities with the opportunity to mitigate volatility in reported earnings caused by measuring related assets and liabilities differently without having to apply complex hedge accounting provisions. The provisions of this Statement apply only to entities that elect the fair value option; however, the amendment to SFAS No. 115 applies to all entities with available-for-sale and trading securities. SFAS No. 159 is effective for Oglethorpe January 1, 2008; however, Oglethorpe has elected not to adopt the provisions of SFAS No. 159 except for those provisions applicable to SFAS No. 115.

In September 2006, the FASB issued SFAS No. 157, "Fair Value Measurements," which defines fair value, establishes a framework for measuring fair value in generally accepted accounting principles (GAAP), and expands disclosures about fair value measurements. SFAS No. 157 does not require any new fair value measurements. However, the application of SFAS No. 157 may change the current practice for measuring fair value. SFAS No. 157 is effective January 1, 2008, and Oglethorpe is evaluating the impact, if any, that the adoption of SFAS No. 157 will have on Oglethorpe's financial position or results of operations.

(D)

Accumulated Comprehensive Deficit.    The table below provides detail of the beginning and ending balance for each classification of accumulated other comprehensive deficit along with the amount of any reclassification adjustments included in margin for each of the periods presented in the Statement of Patronage Capital and Membership Fees and Accumulated Other Comprehensive Deficit. There were no material changes in the nature, timing or amounts of expected (gain) loss reclassified to net margin from the amounts disclosed in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006.

8

Oglethorpe's effective tax rate is zero; therefore, all amounts below are presented net of tax.

	Accumulated Other Comprehensive Deficit
	(dollars in thousands)
	Interest Rate Swap Arrangements		Available-for-sale Securities		Total
Balance at December 31, 2005	($34,910	)	($588	)	($35,498	)
Unrealized gain/(loss)	4,799		252		5,051
(Gain) loss reclassified to net margin	—		(126	)	(126	)
Balance at September 30, 2006	($30,111	)	($462	)	($30,573	)
Balance at December 31, 2006	($28,584	)	($404	)	($28,988	)
Unrealized gain/(loss)	(504	)	278		(226	)
(Gain) loss reclassified to net margin	—		—		—
Balance at September 30, 2007	($29,088	)	($126	)	($29,214	)

(E)

Environmental Matters:    Set forth below are environmental matters that could have an effect on Oglethorpe's financial condition or results of operations. At this time, the resolution of these matters is uncertain, and Oglethorpe has made no accruals for such contingencies and cannot reasonably estimate the possible loss or range of loss with respect to these matters.

1.    General.    As is typical for electric utilities, Oglethorpe is subject to various federal, state and local air and water quality requirements which, among other things, regulate emissions of pollutants, such as particulate matter, sulfur dioxide and nitrogen oxides into the air and discharges of other pollutants, including heat, into waters of the United States. Oglethorpe is also subject to federal, state and local waste disposal requirements that regulate the manner of transportation, storage and disposal of various types of waste.

In general, environmental requirements are becoming increasingly stringent. New requirements may substantially increase the cost of electric service by requiring changes in the design or operation of existing facilities. Failure to comply with these requirements could result in the imposition of civil and criminal penalties as well as the complete shutdown of individual generating units not in compliance. Certain of our debt instruments require us to comply in all material respects with laws, rules, regulations and orders imposed by applicable governmental authorities, which include current or future environmental laws and regulations. Should we fail to be in compliance with these requirements, it would constitute a default under such debt instruments. Oglethorpe cannot provide assurance that it will always be in compliance with current and future regulations.

2.    Clean Air Act.    In January 2003, the Sierra Club appealed an unsuccessful challenge to the air operating permit for the Chattahoochee combined cycle facility to the U.S. Court of Appeals for the Eleventh Circuit. Oglethorpe acquired this facility when it merged with Chattahoochee EMC in May 2003. Oglethorpe intervened in the appeal on behalf of the U.S. Environmental Protection Agency (EPA). In May 2004, the Court ruled in favor of the Sierra Club, invalidating EPA's denial of the petition and remanding the matter to EPA for further consideration. In November 2005, EPA issued an order denying Sierra Club's petition to object to the permit. In January 2006, the Sierra Club filed an appeal of that order to the U.S. Court of Appeals for the Eleventh Circuit. Oglethorpe again intervened in the appeal on behalf of EPA, and on June 26, 2007, the Court

9

ruled in favor of EPA, upholding its decision not to object to the permit. The time for Sierra Club to appeal has not yet expired.

In April 2007, the Sierra Club and the Coosa River Basin Initiative appealed two unsuccessful permit challenges involving operating permit renewals for Plants Scherer (co-owned by Oglethorpe), Bowen, Hammond and Branch to the U.S. Court of Appeals for the Eleventh Circuit. The permits were all challenged on the basis of not including compliance schedules to bring the sources into compliance with the opacity standards, not including an adequate statement of basis, and for Scherer and Bowen, not including compliance schedules to bring the sources into compliance with Prevention of Significant Deterioration requirements. Oglethorpe filed a motion to intervene on behalf of EPA in the case and that motion was granted. Briefing on the case is scheduled to be completed in November 2007. Oral argument is expected to be scheduled for Spring 2008, with a decision likely to be reached by the Court later that year.

(F)

Sale of SO₂ Allowances.    During the nine-month period ended September 30, 2006, Oglethorpe sold SO₂ allowances in excess of its needs to various third parties and received $39.5 million in net proceeds from these sales; there were no sales of SO₂ allowances during the three-month period ended September 30, 2006. The 2006 gain on these sales is reflected in the "Gain on sale of emission allowances" in the accompanying Condensed Statements of Revenues and Expenses (Unaudited). Sales of SO₂ allowances for the nine-month period ended September 30, 2007 totaled $0.4 million.

(G)

Ad Valorem Tax Matters.    For each tax year 2003-2006, the Monroe County Board of Tax Assessors has issued its assessment of Oglethorpe's interest in Plant Scherer for an amount greater than the value determined by the Georgia Department of Revenue (DOR). Oglethorpe has appealed each of the County's valuations by filing a notice of arbitration with the Monroe County Board of Tax Assessors. The arbitration for all four appeals are on hold pending the outcome of a related case filed by GPC, which challenges the authority of Monroe County to change the values determined by the Georgia Department of Revenue. GPC obtained a ruling from the Georgia Court of Appeals that Monroe County did not have the authority to change the values determined by the Georgia Department of Revenues. However, the Georgia Supreme Court granted the County's request to review that ruling. On October 15, 2007, the parties made their oral arguments. Depending on the final outcome of the GPC appeal, the arbitration for Oglethorpe's four appeals will be heard by a panel of arbitrators, with the right to appeal first to the Monroe County Superior Court and then to the Georgia appellate courts. None of the appeals have been sent to the arbitrators, but even if a negative result occurred, Oglethorpe does not believe that it would have a material effect on its financial condition or results of operations.

10

Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations

Results of Operations

For the Three Months and Nine Months Ended September 30, 2007 and 2006

Forward-Looking Statements and Associated Risks

This Quarterly Report on Form 10-Q contains forward-looking statements, including statements regarding, among other items, (i) anticipated transactions by Oglethorpe, (ii) Oglethorpe's future capital requirements and sources of capital and (iii) achievement of a minimum 1.10 Margins for Interest Ratio (MFI Ratio). These forward-looking statements are based largely on Oglethorpe's current expectations and are subject to a number of risks and uncertainties, some of which are beyond Oglethorpe's control. For factors that could cause actual results to differ materially from those anticipated by these forward-looking statements, see Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006, in particular Item 1A-Risk Factors. In light of these risks and uncertainties, there can be no assurance that events anticipated by the forward-looking statements contained in this Quarterly Report will in fact transpire.

Net Margin

Oglethorpe's net margin (deficit) for the three-month and nine-month periods ended September 30, 2007 was $1.1 million and $18.9 million compared to ($1.3) million and $28.5 million for the same periods of 2006. The net margin (deficit) variances for the three-month and nine-month periods ended September 30, 2007 compared to the same periods of 2006 primarily relate to the gain on sale of SO₂ allowances during the first quarter of 2006 as discussed in Note F of the Notes to Unaudited Condensed Financial Statements. See "Operating Revenues" below for discussion regarding impact of gain on sale of SO₂ allowances on Member capacity revenues.

Throughout the year, Oglethorpe monitors its financial results and, with Board approval, makes budget adjustments when and as necessary to ensure that a net margin equivalent to the minimum 1.10 MFI Ratio required under the Mortgage Indenture is achieved. Oglethorpe's management anticipates that the margin for the year ended December 31, 2007 will be approximately $19 million, which will yield an MFI Ratio of 1.10. For additional information on Oglethorpe's margin requirement, see "Management's Discussion and Analysis of Financial Condition and Results of Operations—Summary of Cooperative Operations—Rates and Regulation" in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006.

Operating Revenues

Oglethorpe's operating revenues fluctuate from period to period based on factors including weather and other seasonal factors, load growth in the service territories of its Members, operating costs, availability of electric generation resources, Oglethorpe's decisions of whether to dispatch its owned or purchased resources or Member-owned resources over which it has dispatch rights and by Members' decisions of whether to purchase a portion of their hourly energy requirements from Oglethorpe's resources or from other suppliers.

Total revenues from sales to Members were 4.6% and 4.7% higher in the three-month and nine-month periods ended September 30, 2007 than such revenues for the same periods of 2006. Megawatt-hour (MWh) sales to Members increased 2.1% in the current quarter of 2007 versus the same quarter of 2006 and decreased 0.5% during the nine months ended September 30, 2007 compared to the same period of 2006. The average total revenue per MWh from sales to Members increased 2.4% and 5.3% for the three-month and nine-month periods ended September 30, 2007 compared to the same periods of 2006. For the three-months and nine-months ended September 30, 2007 MWhs supplied by

11

Oglethorpe to its Members varied slightly. There was however, a decrease in MWhs sold to Members primarily due to the termination, effective March 31, 2006, of an agreement to purchase capacity and energy from Georgia Power Company (GPC) at a favorable cost. This decrease was offset somewhat by an increase in MWhs generated and sold to Members. For further discussion regarding purchased power costs and the increase in generation, see "Operating Expenses" below.

The components of Member revenues for the three months and nine months ended September 30, 2007 and 2006 were as follows (amounts in thousands except for cents per kilowatt hour):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2007		2006		2007		2006
Capacity revenues	$	148,828	$	144,661	$	452,689	$	435,613
Energy revenues		196,691		185,633		463,201		439,160
Total	$	345,519	$	330,294	$	915,890	$	874,773
Kilowatt hours sold to Members		6,764,801		6,624,577		17,333,942		17,424,227
Cents per kilowatt hour		5.12¢		4.99¢		5.28¢		5.02¢

Capacity revenues for the three-month and nine-month periods ended September 30, 2007 increased 2.9% and 3.9% compared to the same periods of 2006. Capacity revenues as budgeted and billed for the nine-month period ended September 30, 2007 reflect lower collections of approximately $3.8 million due to the termination of the GPC power purchase agreement effective March 31, 2006. Capacity revenues as budgeted and billed for the nine-month period ended September 30, 2006 reflect lower collections from Members of $20.9 million. Collections from Members were lower in 2006 to offset a portion of the gain on sale of SO₂allowances in 2006. Energy revenues were 6.0% and 5.5% higher for the three-month and nine-month periods ended September 30, 2007 compared to the same periods of 2006. Oglethorpe's average energy revenue per MWh from sales to Members was 3.8% and 6.0% higher for the current periods of 2007 as compared to the same periods of 2006. The increase in energy revenues for the three months and nine months ended September 30, 2007 was primarily due to an increase in the pass through of higher fuel costs. For the nine-month period ended September 30, 2007 the increase in higher fuel costs was offset somewhat by the pass through of lower purchased power costs. For a discussion of fuel costs and purchased power costs see "Operating Expenses" below.

Operating Expenses

Operating expenses for the three-month and nine-month periods ended September 30, 2007 (excluding the gain on the sale of SO₂ allowances of $0.4 million for year-to-date 2007 and $39.5 million for the same period of 2006, respectively,) increased 5.2% and 1.5% compared to the same periods of 2006. The increase in operating expenses for the current quarter of 2007 compared to the same quarter of 2006 was primarily due to higher fuel costs and higher production expenses. The increase in operating expenses for the nine-month period ended September 30, 2007 compared to the same period of 2006 was primarily due to increases in fuel costs and production expenses offset somewhat by lower purchased power and depreciation expenses.

For the three-month and nine-month periods ended September 30, 2007 compared to the same periods of 2006, total fuel costs increased 7.6% and 13.1% while total generation increased 2.5% and 1.6%, respectively. Average fuel costs per MWh increased 5.0% and 11.3% in the current periods of 2007 compared to the same periods of 2006. The increase in total and average fuel costs for the three-month and nine-month periods ended September 30, 2007 as compared to the same periods of 2006 resulted primarily from increased generation of higher cost natural gas-fired generation from both the Chattahoochee energy facility and, to a lesser degree, from the Talbot energy facility.

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Production costs increased 9.8% for the three-month period ended September 30, 2007 compared to the same period of 2006. The increase was primarily due to increased amortization of deferred nuclear refueling outage costs and increased amortization of deferred operations and maintenance (O&M) outage costs for coal-fired generation plants in 2007 compared to 2006. The increase in O&M expenses is also partly attributable to higher expenses at Plant Wansley for Selective Catalytic Reduction (SCR) operations. In addition, administrative and general (A&G) expenses increased by 25.7% (or $1.6 million) partly due to timing of expenses incurred from various membership organizations and partly due to increases in administrative support services from Georgia System Operations Company (GSOC), professional services and payroll expenses.

Total purchased power costs decreased 5.0% and 17.0% for the three-month and nine-month periods ended September 30, 2007 compared to the same periods of 2006. Purchased MWhs decreased 5.5% and 30.0% for the three months and nine months ended September 30, 2007 compared to the same periods of 2006. The average cost per MWh of total purchased power increased 0.6% and 18.5% for the three months and nine months ended September 30, 2007 compared to the same periods of 2006.

Purchased power costs were as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2007		2006		2007		2006
	(dollars in thousands)				(dollars in thousands)
Capacity costs	$	10,426	$	10,305	$	30,606	$	35,172
Energy costs		40,300		43,076		91,276		111,735
Total	$	50,726	$	53,381	$	121,882	$	146,907
Kilowatt hours of purchased power		556,640		589,061		1,252,350		1,788,362
Cents per kilowatt hour		9.11¢		9.06¢		9.73¢		8.22¢

Purchased power capacity costs varied slightly in the current quarter of 2007 compared to the same quarter of 2006 and decreased 13.0% for the nine months ended September 30, 2007 as compared to the same period of 2006. Purchased power energy costs for the three-month and nine-month periods ended September 30, 2007 decreased 6.4% and 18.3% compared to the same periods of 2006. The decrease in purchased power capacity and energy costs for the nine months ended September 30, 2007 compared to the same period of 2006 resulted primarily from the decrease in purchased MWhs, which in turn resulted primarily from the termination of the GPC agreement, effective March 31, 2006, as discussed above. The average cost of purchased power energy decreased 1.0% and increased 16.7% for the three-month and six-month periods ended September 30, 2007 compared to the same periods of 2006. Purchased power energy costs, purchased MWhs and average cost of energy per MWh varied slightly for the current quarter of 2007 compared to the same quarter of 2006. The decrease in purchased power energy costs and volume of purchased power MWhs along with the increase in average energy cost per MWh during the nine-month period ended September 30, 2007 compared to the same period of 2006 was primarily due to the termination of the GPC purchased power agreement (with its favorable energy cost to Oglethorpe), effective March 31, 2006. The decrease in MWhs acquired under Oglethorpe's energy replacement program which replaces power from Oglethorpe owned generation facilities with lower price spot market purchased power energy also contributed to the decrease in purchased power energy costs and to the volume of purchased power MWhs.

Accretion expense represents the change in the asset retirement obligations due to the passage of time. For nuclear decommissioning, Oglethorpe records a regulatory asset or liability for the timing difference in accretion recognized under SFAS No. 143, "Accounting for Asset Retirement Obligations", compared to the expense recovered for ratemaking purposes. The accretion expense recognized is equal to the lesser of the earnings from both the decommissioning trust fund and the internal

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decommissioning fund or the ARO nuclear decommissioning expenses to be recognized under FAS No. 143. The earnings in the three-month and nine-month periods ended September 30, 2007 were $0.9 million higher and $1.5 million lower than in the same periods of 2006. As a result, accretion expense increased 51.4% and decreased 4.9%, respectively, during the three and nine months ended September 30, 2007 as compared to the same periods of 2006.

Depreciation and amortization expense decreased 9.3% (or $11.2 million) for the nine-month period ended September 30, 2007 compared to the same period of 2006. Depreciation and amortization expenses in 2007 were lower primarily because of accelerated amortization of deferred amortization of capital leases taken in 2006 in order to offset a portion of the gain from the 2006 sale of SO₂ allowances. Depreciation and amortization expense remained relatively flat during the three months ended September 30, 2007 as compared to the same period of 2006.

Other Income

Investment income increased 40.0% (or $2.7 million) and 11.4% (or $3.3 million) in the three-month and nine-month periods in 2007 compared to the same periods of 2006. The increase for the three months and nine months ended September 30, 2007 compared to the same periods of 2006 resulted primarily from increased interest earnings on cash and cash equivalent investments principally as a result of higher average investment balances. The higher investment balances resulted primarily from cash generated due to the issuance of additional debt as discussed in "Interest Charges" below. The increase to investment income for the nine months ended September 30, 2007 was offset somewhat partly by the elimination of earnings from funds deposited in the Rural Utilities Service (RUS) Cushion of Credit Account and partly from lower earnings from the decommissioning trust fund as discussed above. Funds in the Cushion of Credit Account were utilized to pay debt service costs and as of September 30, 2006, there were no remaining deposits invested in the account; therefore, there has not been any additional income relative to these investments in subsequent periods.

Interest Charges

Interest on long-term debt and capital leases increased by 5.0% and 5.1% in the three months and nine months ended September 30, 2007 compared to the same periods of 2006. This increase resulted primarily from the issuance of $300 million in first mortgage bonds in October 2006; the proceeds are being used to fund the installation of environmental controls facilities at Plant Scherer, one of Oglethorpe's coal-fired generating plants, and for general corporate purposes.

Balance Sheet Analysis as of September 30, 2007

Assets

Property additions for the nine months ended September 30, 2007 totaled $123.1 million. Included in this total were expenditures of approximately $26 million for nuclear fuel and approximately $53 million for environmental control projects. The remaining expenditures were primarily for normal additions and replacements to existing generation facilities.

Construction work in progress increased by $71.4 million in the nine months ended September 30, 2007, primarily due to costs incurred for various replacement and improvement projects (including environmental control) at existing generation facilities.

The $15.0 million decrease in long-term investments was principally due to a $21.2 million decrease in the holdings of auction rate securities. The funds were primarily re-invested in commercial paper, which is short-term in nature.

Cash and cash equivalents decreased $97.4 million principally due to the timing of certain principal and interest payments, property additions and payments to GPC.

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Restricted cash and cash equivalents at December 31, 2006 represented a portion of the proceeds obtained from the refinancing of certain indebtedness associated with pollution control bonds (PCBs) in October 2006. These proceeds, which were on deposit with a trustee, were subsequently used in the first quarter of 2007 to pay principal related to the refinanced PCB debt that matured in January 2007.

Receivables increased $31.3 million, or 34.2%. The increase was due in part to an increase of approximately $13.3 million in energy revenue (September 2007 vs. December 2006), which was largely a result of increased generation at the natural gas fired plants. In addition, the December 31, 2006 receivables balance included approximately $10.1 million of credits available to the Members for a Board approved reduction to 2006 revenue requirements. These credits were realized by the Members during the first quarter of 2007.

Deferred outage costs increased $4.5 million (net of amortization), or 17.6%, as a result of the deferral of approximately $9.0 million of refueling outage costs incurred at Plant Hatch Unit No. 2 and $11.3 million at Plant Vogtle Unit No. 2 during the nine months ended September 30, 2007. In addition, approximately $1.9 million was deferred for scheduled major maintenance costs at Plant Wansley Unit No. 1 and $5.6 million at Plant Scherer Unit No. 2. Deferred outage costs are amortized over the plant's operating cycle.

As a result of the adoption of FIN 48, Oglethorpe has reversed the valuation allowance of a $72 million deferred tax asset. For further discussion regarding the deferred tax asset see Note B of the Notes to Unaudited Condensed Financial Statements.

Other deferred charges increased $2.4 million primarily due to a $1.9 million increase in equipment prepayments to GPC. These prepayments are associated with refueling outages at Plant Hatch and Plant Vogtle.

Equity and Liabilities

Long-term debt and capital leases due within one year decreased 52.2%, or $122.4 million. The decrease was primarily a result of the reclassification of certain Federal Financing Bank (FFB) and Pollution Control Bond (PCB) debt to long-term debt. The reclassification was due in part to the maturity extension of $428 million of certain FFB debt in May 2007. In October 2007, Oglethorpe also refinanced $454 million of certain FFB debt and $182 million of certain PCB debt. The short-term portions of these debts were also reclassified to long-term debt in accordance with SFAS No. 6, "Classification of Short-term Obligations Expected to be Refinanced". For further discussion regarding the extension of the FFB debt maturities and FFB debt prepayment, see "Financings" below.

The decrease in accrued interest was largely due to the timing of a principal and interest payment for the Plant Scherer Unit No. 2 capital lease obligation. The December 31, 2006 accrued interest balance included an amount for the semi-annual lease payment that was due on January 2, 2007, while the balance at September 30, 2007 included only three months of accrued interest.

As a result of a $5.5 million increase in the unrealized gain associated with the nuclear decommissioning fund and an additional $1.3 million of accretion expense recorded as a result of decommissioning fund earnings, the deferred liability associated with asset retirement obligations increased by $7.3 million. For further discussion regarding accretion expense, see "Operating Expenses" above.

As a result of the adoption of FIN 48, Oglethorpe has recorded a $72 million long-term contingent tax liability. For further discussion regarding the long-term contingent tax liability see Note B of the Notes to Unaudited Condensed Financial Statements.

Other deferred credits and liabilities increased primarily due to a $4.5 million increase in liabilities associated with payments made to Oglethorpe by its Members. Approximately $2.2 million of the

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increase is associated with funding the future overhaul of the combustion turbine plants. An additional $2.3 million is associated with the funding of future debt payments.

Financial Condition

Capital Requirements and Liquidity and Sources of Capital

Environmental Capital Requirements

Oglethorpe's future capital expenditures depend in part on future environmental regulations, including future implementation of existing laws and regulations and how Oglethorpe and the other co-owners of coal-fired Plants Scherer and Wansley choose to comply with these regulations, once finalized. Regulations recently adopted by the Georgia Environmental Protection Division specify certain environmental control equipment that must be added to Georgia electric generating units, and by specific dates, including Plants Scherer and Wansley. As described in "MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS—Financial Condition—Capital Requirements" in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006, Oglethorpe forecasted expenditures of $252 million for environmental compliance in 2007-2009. Oglethorpe also reported the likelihood of being required to spend $400 million to $600 million beyond 2009, in anticipation of finalization of regulations. As design work has continued to determine how best to retrofit the units with the required equipment, and as the construction environment is now being evaluated, the estimated cost to install these retrofits continues to be being refined. Current indications are that the capital expenditures required beyond 2009 will exceed $600 million, maybe by as much as $200 million to $300 million. Large construction projects such as these entail certain risks, as described in Item 1A of Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006. There can be no assurance that the cost of compliance with these regulations will not be higher, nor that future regulations will not require additional reductions in emissions or earlier compliance. See Note E of the Notes to Unaudited Condensed Financial Statements for more information on environmental compliance matters.

Liquidity

As of September 30, 2007, Oglethorpe had $876 million of unrestricted available liquidity to meet short-term cash needs and liquidity requirements. This liquidity consisted of (i) approximately $326 million in cash and cash equivalents, and (ii) $550 million available under three committed working capital line of credit facilities.

Oglethorpe has in place a five-year $450 million committed working capital line of credit supporting its commercial paper program that matures in July 2012. The line of credit contains a financial covenant requiring Oglethorpe to maintain patronage capital of at least $400 million, and at September 30, 2007, Oglethorpe had patronage capital in excess of $516 million. The facility also contains an additional covenant limiting Oglethorpe's secured indebtedness to no more than $8.5 billion and its unsecured indebtedness to no more than $4.0 billion. Oglethorpe's current debt levels are well below these thresholds.

Oglethorpe also has in place two $50 million committed lines of credit, one with National Rural Utilities Cooperative Finance Corporation ("CFC") that matures in October 2008, and one with CoBank, ACB that matures in November 2008. Oglethorpe expects to renew the CFC and CoBank credit facilities, as needed, prior to their respective expiration dates.

There are currently no amounts outstanding under any of the three committed credit facilities discussed above.

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Oglethorpe also had $40 million invested in auction rate securities at September 30, 2007. These securities have maturities in excess of one year and as such are classified as long-term investments. However, most of these securities re-price in auctions that occur every 35 days or less, and Oglethorpe could seek to liquidate these securities at the end of any auction period.

Financings

Oglethorpe has embarked on a program to refinance or otherwise reamortize a portion of its FFB and PCB debt to extend the maturities of this debt in connection with the extension, in 2005, of its Member wholesale power contracts from 2025 to 2050. In connection with this program, on October 3, 2007 Oglethorpe issued $500,000,000 of Series 2007 First Mortgage Bonds, the proceeds of which were used to prepay approximately $450 million of existing FFB debt and for other general purposes. This new fixed rate debt is subject to mandatory sinking fund redemptions occurring in 2024 to 2030, with a final maturity in 2031.

Also in connection with the debt reamortization program, on October 25, 2007 Oglethorpe issued $182 million of Series 2007 PCB debt, which was used to refinance a like amount of existing PCB debt, including $22 million scheduled to mature on January 1, 2008, $122 million scheduled to mature on January 1, 2018 and $38 million scheduled to mature on January 1, 2024. This $182 million of new variable rate PCB debt has bullet maturities that come due in the 2038 to 2040 time frame. The debt was secured under the Mortgage Indenture. Georgia Transmission Corporation (GTC) elected to participate in this refunding and assumed an obligation to pay $3.7 million of the Burke Series 2007A debt. See "MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS—Financial Condition—Off-Balance Sheet Arrangements—GTC Debt Assumption" in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006.

In September 2007, the RUS approved a $442 million loan for Oglethorpe representing two outstanding loan applications that were pending. Oglethorpe does not anticipate closing on this loan and advancing any funds thereunder until mid-2008.

For more detailed information regarding Oglethorpe's financing plans, see "MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS—Financial Condition—Financing Activities" in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006.

Critical Accounting Policy

Oglethorpe's critical accounting policies have not changed from the policy reported in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended Dec. 31, 2006 except for the estimate recorded in conjunction with the adoption of FIN 48. See Note B of the Notes to Unaudited Condensed Financial Statements for further discussion.

New Accounting Interpretation and Standards

For discussion of FIN 48 and SFAS No. 159 and 157 see Notes B and C of the Notes to Unaudited Condensed Financial Statements.

Item 3. Quantitative and Qualitative Disclosures About Market Risk

Oglethorpe's market risks have not changed materially from the risks reported in Oglethorpe's Annual Report on Form 10-K for the fiscal year ended Dec. 31, 2006.

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Item 4. Controls and Procedures

As of September 30, 2007, Oglethorpe had carried out an evaluation, under the supervision and with the participation of its management, including its President and Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of its disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended). Based on this evaluation, the President and Chief Executive Officer and the Chief Financial Officer concluded that Oglethorpe's disclosure controls and procedures are effective.

There have been no changes in Oglethorpe's internal control over financial reporting or other factors that occurred during the quarter ended September 30, 2007 that have materially affected, or are reasonably likely to materially affect, Oglethorpe's internal control over financial reporting.

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PART II — OTHER INFORMATION

Item 1. Legal Proceedings

Environmental Matters

For information about legal and regulatory proceedings regarding environmental matters that could have an effect on Oglethorpe, see Note E of the Notes to Unaudited Condensed Financial Statements.

Item 1A. Risk Factors

There have not been any material changes in Oglethorpe's risk factors from those disclosed in Item 1A of Oglethorpe's Annual Report on Form 10-K for the fiscal year ended December 31, 2006.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds

Not Applicable.

Item 3. Defaults upon Senior Securities

Not Applicable.

Item 4. Submission of Matters to a Vote of Security Holders

Not Applicable.

Item 5. Other Information

Not Applicable.

Item 6. Exhibits

Number	Description
4.7.1(oo)	Fortieth Supplemental Indenture, dated as of October 1, 2007, made by Oglethorpe to U.S. Bank National Association, as trustee, relating to the Oglethorpe Power Corporation First Mortgage Bonds, Series 2007.
4.7.1(pp)	Forty-First Supplemental Indenture, dated as of October 1, 2007, made by Oglethorpe to U.S. Bank National Association, as trustee, relating to the Series 2007A (Appling) Note, Series 2007B (Appling) Note, Series 2007A (Burke) Note, Series 2007B (Burke) Note, Series 2007C (Burke) Note, Series 2007D (Burke) Note, Series 2007E (Burke) Note, Series 2007F (Burke) Note and Series 2007A (Monroe) Note.
31.1	Rule 13a-14(a)/15d-14(a) Certification, by Thomas A. Smith (Principal Executive Officer).
31.2	Rule 13a-14(a)/15d-14(a) Certification, by Elizabeth B. Higgins (Principal Financial Officer).
32.1	Certification Pursuant to 18 U.S.C. 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, by Thomas A. Smith (Principal Executive Officer).
32.2	Certification Pursuant to 18 U.S.C. 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, by Elizabeth B. Higgins (Principal Financial Officer).

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SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

		Oglethorpe Power Corporation (An Electric Membership Corporation)
Date: November 13, 2007	By:	/s/ Thomas A. Smith Thomas A. Smith President and Chief Executive Officer
Date: November 13, 2007		/s/ Elizabeth B. Higgins Elizabeth B. Higgins Chief Financial Officer (Principal Financial Officer)

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PART I—FINANCIAL INFORMATION
Item 1. Financial Statements
Oglethorpe Power Corporation Notes to Unaudited Condensed Financial Statements September 30, 2007 and 2006
SIGNATURES

EX-4.7.1(OO)

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EX-4.7.1(PP)

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EXHIBIT 4.7.1(pp)

Upon recording, return to:
Ms. Shawne M. Keenan
Sutherland Asbill & Brennan LLP
999 Peachtree Street, N.E.
Atlanta, Georgia 30309-3996

PURSUANT TO §44-14-35.1 OF OFFICIAL CODE OF GEORGIA ANNOTATED, THIS INSTRUMENT EMBRACES,
COVERS AND CONVEYS SECURITY TITLE TO AFTER-ACQUIRED PROPERTY OF THE GRANTOR

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION),
GRANTOR,

to

U.S. BANK NATIONAL ASSOCIATION,
TRUSTEE

FORTY-FIRST SUPPLEMENTAL
INDENTURE

Relating to the

Series 2007A (Appling) Note
Series 2007B (Appling) Note
Series 2007A (Burke) Note
Series 2007B (Burke) Note
Series 2007C (Burke) Note
Series 2007D (Burke) Note
Series 2007E (Burke) Note
Series 2007F (Burke) Note
Series 2007A (Monroe) Note

Dated as of October 1, 2007

FIRST MORTGAGE OBLIGATIONS

THIS FORTY-FIRST SUPPLEMENTAL INDENTURE, dated as of October 1, 2007, is between OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION), formerly known as Oglethorpe Power Corporation (An Electric Membership Generation & Transmission Corporation), an electric membership corporation organized and existing under the laws of the State of Georgia, as Grantor (hereinafter called the "Company"), and U.S. BANK NATIONAL ASSOCIATION, a national banking association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as Trustee (in such capacity, the "Trustee").

WHEREAS, the Company has heretofore executed and delivered to the Trustee an Indenture, dated as of March 1, 1997 (the "Original Indenture") for the purpose of securing its Existing Obligations and providing for the authentication and delivery of Additional Obligations by the Trustee from time to time under the Original Indenture (capitalized terms used herein and not otherwise defined shall have the meanings assigned to them in the Original Indenture);

WHEREAS, the Company has heretofore executed and delivered to the Trustee forty Supplemental Indentures (the Original Indenture, as heretofore, hereby and hereafter supplemented and modified, being herein sometimes called the "Indenture"), and the Original Indenture and the forty Supplemental Indentures have been recorded as set forth on Schedule 1;

Series 2007A Appling Bonds

WHEREAS, the Appling Authority has agreed to issue $20,530,000 in aggregate principal amount of Development Authority of Appling County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Hatch Project), Series 2007A (the "Series 2007A Appling Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007A Appling Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007A Appling Bonds is evidenced by that certain Series 2007A (Appling) Note, dated the date of its authentication (the "Series 2007A (Appling) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007A Appling Trustee"), as assignee and pledgee of the Appling Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007A Appling Indenture"), between the Appling Authority and the Series 2007A Appling Trustee;

Series 2007B Appling Bonds

WHEREAS, the Appling Authority has agreed to issue $20,000,000 in aggregate principal amount of Development Authority of Appling County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Hatch Project), Series 2007B (the "Series 2007B Appling Bonds"; and together with the Series 2007A Appling Bonds, the "Appling Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007B Appling Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007B Appling Bonds is evidenced by that certain Series 2007B (Appling) Note, dated the date of its authentication (the "Series 2007B (Appling) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007B Appling Trustee"), as assignee and pledgee of the Appling Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007B Appling Indenture"), between the Appling Authority and the Series 2007B Appling Trustee;

WHEREAS, the Company will use the proceeds from the sale of the Appling Bonds to refund (i) the entire outstanding principal amount of the Appling Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Hatch Project), Series 2002, and (ii) the entire outstanding principal amount of the Appling Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Hatch Project), Series 2003A;

Series 2007A Burke Bonds

WHEREAS, the Burke Authority has agreed to issue $27,105,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007A (the "Series 2007A Burke Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007A Burke Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007A Burke Bonds is evidenced by that certain Series 2007A (Burke) Note, dated the date of its authentication (the "Series 2007A (Burke) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007A Burke Trustee"), as assignee and pledgee of the Burke Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007A Burke Indenture"), between the Burke Authority and the Series 2007A Burke Trustee;

Series 2007B Burke Bonds

WHEREAS, the Burke Authority has agreed to issue $27,210,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007B (the "Series 2007B Burke Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007B Burke Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007B Burke Bonds is evidenced by that certain Series 2007B (Burke) Note, dated the date of its authentication (the "Series 2007B (Burke) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007B Burke Trustee"), as assignee and pledgee of the Burke Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007B Burke Indenture"), between the Burke Authority and the Series 2007B Burke Trustee;

Series 2007C Burke Bonds

WHEREAS, the Burke Authority has agreed to issue $20,000,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007C (the "Series 2007C Burke Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007C Burke Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007C Burke Bonds is evidenced by that certain Series 2007C (Burke) Note, dated the date of its authentication (the "Series 2007C (Burke) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007C Burke Trustee"), as assignee and pledgee of the Burke Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007C Burke Indenture"), between the Burke Authority and the Series 2007C Burke Trustee;

Series 2007D Burke Bonds

WHEREAS, the Burke Authority has agreed to issue $20,000,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007D (the "Series 2007D Burke Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007D Burke Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007D Burke Bonds is evidenced by that certain Series 2007D (Burke) Note, dated the date of its

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authentication (the "Series 2007D (Burke) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007D Burke Trustee"), as assignee and pledgee of the Burke Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007D Burke Indenture"), between the Burke Authority and the Series 2007D Burke Trustee;

Series 2007E Burke Bonds

WHEREAS, the Burke Authority has agreed to issue $20,000,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007E (the "Series 2007E Burke Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007E Burke Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007E Burke Bonds is evidenced by that certain Series 2007E (Burke) Note, dated the date of its authentication (the "Series 2007E (Burke) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007E Burke Trustee"), as assignee and pledgee of the Burke Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007E Burke Indenture"), between the Burke Authority and the Series 2007E Burke Trustee;

Series 2007F Burke Bonds

WHEREAS, the Burke Authority has agreed to issue $10,390,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007F (the "Series 2007F Burke Bonds"; and together with the Series 2007A Burke Bonds, the Series 2007B Burke Bonds, the Series 2007C Burke Bonds, the Series 2007D Burke Bonds and the Series 2007E Burke Bonds, the "Burke Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007F Burke Loan Agreement");

WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007F Burke Bonds is evidenced by that certain Series 2007F (Burke) Note, dated the date of its authentication (the "Series 2007F (Burke) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007F Burke Trustee"), as assignee and pledgee of the Burke Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007F Burke Indenture"), between the Burke Authority and the Series 2007F Burke Trustee;

WHEREAS, the Company will use the proceeds from the sale of the Burke Bonds, together with other amounts provided by Oglethorpe, to refund (i) the portion of each of the Burke Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 1993A and Series 1994A, subject to mandatory sinking fund redemption on January 1, 2008; (ii) the entire outstanding principal amount of the Burke Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2002A, (iii) the entire outstanding principal amount of the Burke Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2002B, and (iv) the entire outstanding principal amount of the Burke Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2002C;

Series 2007A Monroe Bonds

WHEREAS, the Monroe Authority has agreed to issue $16,655,000 in aggregate principal amount of Development Authority of Monroe County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Scherer Project), Series 2007A (the "Series 2007A Monroe Bonds"), and to loan the proceeds from the sale thereof to the Company pursuant to that certain Loan Agreement, dated as of October 1, 2007, relating thereto (the "Series 2007A Monroe Loan Agreement");

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WHEREAS, the Company's obligation to repay the loan of the proceeds of the Series 2007A Monroe Bonds is evidenced by that certain Series 2007A (Monroe) Note, dated the date of its authentication (the "Series 2007A (Monroe) Note"), from the Company to U.S. Bank National Association, as trustee (in such capacity, the "Series 2007A Monroe Trustee"), as assignee and pledgee of the Monroe Authority pursuant to the Trust Indenture, dated as of October 1, 2007 (the "Series 2007A Monroe Indenture"), between the Monroe Authority and the Series 2007A Monroe Trustee;

WHEREAS, the Company will use the proceeds from the sale of the Series 2007A Monroe Bonds to refund (i) the portion of the Monroe Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Scherer Project), Series 1992A, maturing on January 1, 2008, and (ii) the entire outstanding principal amount of the Monroe Authority's Pollution Control Revenue Bonds (Oglethorpe Power Corporation Scherer Project), Series 2002;

WHEREAS, the Company desires to execute and deliver this Forty-First Supplemental Indenture, in accordance with the provisions of the Original Indenture, for the purpose of providing for the creation and designation of the Series 2007A (Appling) Note, the Series 2007B (Appling) Note, the Series 2007A (Burke) Note, the Series 2007B (Burke) Note, the Series 2007C (Burke) Note, the Series 2007D (Burke) Note, the Series 2007E (Burke) Note, the Series 2007F (Burke) Note and the Series 2007A (Monroe) Note (collectively, the "Notes") as Additional Obligations and specifying the form and provisions thereof;

WHEREAS, Section 12.1 of the Original Indenture provides that, without the consent of the Holders of any of the Obligations, the Company, when authorized by a Board Resolution, and the Trustee, may enter into Supplemental Indentures for the purposes and subject to the conditions set forth in said Section 12.1, including to create additional series of Obligations under the Indenture and to make provisions for such additional series of Obligations; and

WHEREAS, all acts and proceedings required by law and by the Articles of Incorporation and Bylaws of the Company necessary to secure under the Indenture the payment of the principal of (and premium, if any) and interest on the Notes, to make the Notes to be issued hereunder, when executed by the Company, authenticated and delivered by the Trustee and duly issued, the valid, binding and legal obligation of the Company, and to constitute the Indenture a valid and binding lien for the security of the Notes, in accordance with its terms, have been done and taken; and the execution and delivery of this Forty-First Supplemental Indenture has been in all respects duly authorized by the Company.

NOW, THEREFORE, THIS FORTY-FIRST SUPPLEMENTAL INDENTURE WITNESSES, that, to secure the payment of the principal of (and premium, if any) and interest on the Outstanding Secured Obligations, including, when authenticated and delivered, the Notes, to confirm the lien of the Indenture upon the Trust Estate, including property purchased, constructed or otherwise acquired by the Company since the date of execution of the Original Indenture, to secure performance of the covenants therein and herein contained, to declare the terms and conditions on which the Notes are secured, and in consideration of the premises thereof and hereof, the Company by these presents does grant, bargain, sell, alienate, remise, release, convey, assign, transfer, mortgage, hypothecate, pledge, set over and confirm to the Trustee, and its successors and assigns in the trust created thereby and hereby, in trust, all property, rights, privileges and franchises (other than Excepted Property or Excludable Property) of the Company, whether now owned or hereafter acquired, of the character described in the Granting Clauses of the Original Indenture, wherever located, including all such property, rights, privileges and franchises acquired since the date of execution of the Original Indenture, including, without limitation, all property described on Exhibit A attached hereto, subject to all exceptions, reservations and matters of the character referred to in the Indenture, and does grant a security interest therein for the purposes expressed herein and in the Original Indenture subject in all cases to

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Sections 5.2 and 11.2 B of the Original Indenture and to the rights of the Company under the Original Indenture, including the rights set forth in Article V thereof; but expressly excepting and excluding from the lien and operation of the Indenture all properties of the character specifically excepted as "Excepted Property" or "Excludable Property" in the Original Indenture to the extent contemplated thereby.

PROVIDED, HOWEVER, that if, upon the occurrence of an Event of Default, the Trustee, or any separate trustee or co-trustee appointed under Section 9.14 of the Original Indenture or any receiver appointed pursuant to statutory provision or order of court, shall have entered into possession of all or substantially all of the Trust Estate, all the Excepted Property described or referred to in Paragraphs A through H, inclusive, of "Excepted Property" in the Original Indenture then owned or thereafter acquired by the Company, shall immediately, and, in the case of any Excepted Property described or referred to in Paragraphs I, J, L, N and P of "Excepted Property" in the Original Indenture (excluding the property described in Section 2 of Exhibit B in the Original Indenture), upon demand of the Trustee or such other trustee or receiver, become subject to the lien of the Indenture to the extent permitted by law, and the Trustee or such other trustee or receiver may, to the extent permitted by law, at the same time likewise take possession thereof, and whenever all Events of Default shall have been cured and the possession of all or substantially all of the Trust Estate shall have been restored to the Company, such Excepted Property shall again be excepted and excluded from the lien of the Indenture to the extent and otherwise as hereinabove set forth and as set forth in the Indenture.

        The Company may, however, pursuant to the Granting Clause Third of the Original Indenture, subject to the lien of the Indenture any Excepted Property or Excludable Property, whereupon the same shall cease to be Excepted Property or Excludable Property.

TO HAVE AND TO HOLD all such property, rights, privileges and franchises hereby and hereafter (by a Supplemental Indenture or otherwise) granted, bargained, sold, alienated, remised, released, conveyed, assigned, transferred, mortgaged, hypothecated, pledged, set over or confirmed as aforesaid, or intended, agreed or covenanted so to be, together with all the tenements, hereditaments and appurtenances thereto appertaining (said properties, rights, privileges and franchises, including any cash and securities hereafter deposited or required to be deposited with the Trustee (other than any such cash which is specifically stated in the Indenture not to be deemed part of the Trust Estate) being part of the Trust Estate), unto the Trustee, and its successors and assigns in the trust herein created by the Indenture, forever.

SUBJECT, HOWEVER, to (i) Permitted Exceptions and (ii) to the extent permitted by Section 13.6 of the Original Indenture as to property hereafter acquired (a) any duly recorded or perfected prior mortgage or other lien that may exist thereon at the date of the acquisition thereof by the Company and (b) purchase money mortgages, other purchase money liens, chattel mortgages, conditional sales agreements or other title retention agreements created by the Company at the time of acquisition thereof.

BUT IN TRUST, NEVERTHELESS, with power of sale, for the equal and proportionate benefit and security of the Holders from time to time of all the Outstanding Secured Obligations without any priority of any such Obligation over any other such Obligation and for the enforcement of the payment of such Obligations in accordance with their terms.

UPON CONDITION that, until the happening of an Event of Default and subject to the provisions of Article V of the Original Indenture, and not in limitation of the rights elsewhere provided in the Original Indenture, including the rights set forth in Article V of the Original Indenture, the Company shall be permitted to (i) possess and use the Trust Estate, except cash, securities, Designated Qualifying Securities and other personal property deposited, or required to be deposited, with the Trustee, (ii) explore for, mine, extract, separate and dispose of coal, ore, gas, oil and other minerals, and harvest

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standing timber, and (iii) receive and use the rents, issues, profits, revenues and other income, products and proceeds of the Trust Estate.

THE INDENTURE, INCLUDING THIS FORTY-FIRST SUPPLEMENTAL INDENTURE, is intended to operate and is to be construed as a deed passing title to the Trust Estate and is made under the provisions of the laws of the State of Georgia relating to deeds to secure debt, and not as a mortgage or deed of trust, and is given to secure the Outstanding Secured Obligations. Should the indebtedness secured by the Indenture be paid according to the tenor and effect thereof when the same shall become due and payable and should the Company perform all covenants contained in the Indenture in a timely manner, then the Indenture shall be canceled and surrendered.

AND IT IS HEREBY COVENANTED AND DECLARED that the Notes are to be authenticated and delivered and the Trust Estate is to be held and applied by the Trustee, subject to the covenants, conditions and trusts set forth herein and in the Indenture, and the Company does hereby covenant and agree to and with the Trustee, for the equal and proportionate benefit of all Holders of the Outstanding Secured Obligations, as follows:

ARTICLE I

THE NOTES AND CERTAIN PROVISIONS RELATING THERETO

Section 1.1    Authorization and Terms of the Notes.

A.

The Series 2007A (Appling) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007A (Appling) Note" (hereinafter referred to as the "Series 2007A (Appling) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007A (Appling) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $20,530,000.

        The Series 2007A (Appling) Note shall be dated the date of its authentication. The Series 2007A (Appling) Note shall mature on January 1, 2038 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007A (Appling) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007A Appling Trustee.

        All payments made on the Series 2007A (Appling) Note shall be made to the Series 2007A Appling Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

B.

The Series 2007B (Appling) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007B (Appling) Note" (hereinafter referred to as the "Series 2007B (Appling) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007B (Appling) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $20,000,000.

        The Series 2007B (Appling) Note shall be dated the date of its authentication. The Series 2007B (Appling) Note shall mature on January 1, 2038 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007B (Appling) Note shall be authenticated and

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delivered to, and made payable to, U.S. Bank National Association, as the Series 2007B Appling Trustee.

        All payments made on the Series 2007B (Appling) Note shall be made to the Series 2007B Appling Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

C.

The Series 2007A (Burke) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007A (Burke) Note" (hereinafter referred to as the "Series 2007A (Burke) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007A (Burke) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $27,105,000.

        The Series 2007A (Burke) Note shall be dated the date of its authentication. The Series 2007A (Burke) Note shall mature on January 1, 2039 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007A (Burke) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007A Burke Trustee.

        All payments made on the Series 2007A (Burke) Note shall be made to the Series 2007A Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

D.

The Series 2007B (Burke) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007B (Burke) Note" (hereinafter referred to as the "Series 2007B (Burke) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007B (Burke) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $27,210,000.

        The Series 2007B (Burke) Note shall be dated the date of its authentication. The Series 2007B (Burke) Note shall mature on January 1, 2038 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007B (Burke) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007B Burke Trustee.

        All payments made on the Series 2007B (Burke) Note shall be made to the Series 2007B Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

E.

The Series 2007C (Burke) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007C (Burke) Note" (hereinafter referred to as the "Series 2007C (Burke) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007C (Burke) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $20,000,000.

        The Series 2007C (Burke) Note shall be dated the date of its authentication. The Series 2007C (Burke) Note shall mature on January 1, 2039 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note

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prescribed pursuant to Section 1.2 hereof. The Series 2007C (Burke) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007C Burke Trustee.

        All payments made on the Series 2007C (Burke) Note shall be made to the Series 2007C Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

F.

The Series 2007D (Burke) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007D (Burke) Note" (hereinafter referred to as the "Series 2007D (Burke) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007D (Burke) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $20,000,000.

        The Series 2007D (Burke) Note shall be dated the date of its authentication. The Series 2007D (Burke) Note shall mature on January 1, 2040 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007D (Burke) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007D Burke Trustee.

        All payments made on the Series 2007D (Burke) Note shall be made to the Series 2007D Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

G.

The Series 2007E (Burke) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007E (Burke) Note" (hereinafter referred to as the "Series 2007E (Burke) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007E (Burke) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $20,000,000.

        The Series 2007E (Burke) Note shall be dated the date of its authentication. The Series 2007E (Burke) Note shall mature on January 1, 2040 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007E (Burke) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007E Burke Trustee.

        All payments made on the Series 2007E (Burke) Note shall be made to the Series 2007E Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

H.

The Series 2007F (Burke) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007F (Burke) Note" (hereinafter referred to as the "Series 2007F (Burke) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007F (Burke) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $10,390,000.

        The Series 2007F (Burke) Note shall be dated the date of its authentication. The Series 2007F (Burke) Note shall mature on January 1, 2039 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note

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prescribed pursuant to Section 1.2 hereof. The Series 2007F (Burke) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007F Burke Trustee.

        All payments made on the Series 2007F (Burke) Note shall be made to the Series 2007F Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

I.

The Series 2007A (Monroe) Note

        There shall be created and established an Additional Obligation in the form of a promissory note known as and entitled the "Series 2007A (Monroe) Note" (hereinafter referred to as the "Series 2007A (Monroe) Note"), the form, terms and conditions of which shall be substantially as set forth in or prescribed pursuant to this Section and Section 1.2 hereof. The aggregate principal amount of the Series 2007A (Monroe) Note which shall be authenticated and delivered and Outstanding at any one time is limited to $16,655,000.

        The Series 2007A (Monroe) Note shall be dated the date of its authentication. The Series 2007A (Monroe) Note shall mature on January 1, 2038 and shall bear interest from the date of its authentication to the date of its maturity at rates calculated as provided for in the form of note prescribed pursuant to Section 1.2 hereof. The Series 2007A (Monroe) Note shall be authenticated and delivered to, and made payable to, U.S. Bank National Association, as the Series 2007A Monroe Trustee.

        All payments made on the Series 2007A (Monroe) Note shall be made to the Series 2007A Monroe Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the date payment is due.

Section 1.2    Form of the Notes.

A.

The Series 2007A (Appling) Note

        The Series 2007A (Appling) Note and the Trustee's certificate of authentication for the Series 2007A (Appling) Note shall be substantially in the form of Exhibit B attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

B.

The Series 2007B (Appling) Note

        The Series 2007B (Appling) Note and the Trustee's certificate of authentication for the Series 2007B (Appling) Note shall be substantially in the form of Exhibit C attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

C.

The Series 2007A (Burke) Note

        The Series 2007A (Burke) Note and the Trustee's certificate of authentication for the Series 2007A (Burke) Note shall be substantially in the form of Exhibit D attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

D.

The Series 2007B (Burke) Note

        The Series 2007B (Burke) Note and the Trustee's certificate of authentication for the Series 2007B (Burke) Note shall be substantially in the form of Exhibit E attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

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E.

The Series 2007C (Burke) Note

        The Series 2007C (Burke) Note and the Trustee's certificate of authentication for the Series 2007C (Burke) Note shall be substantially in the form of Exhibit F attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

F.

The Series 2007D (Burke) Note

        The Series 2007D (Burke) Note and the Trustee's certificate of authentication for the Series 2007D (Burke) Note shall be substantially in the form of Exhibit G attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

G.

The Series 2007E (Burke) Note

        The Series 2007E (Burke) Note and the Trustee's certificate of authentication for the Series 2007E (Burke) Note shall be substantially in the form of Exhibit H attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

H.

The Series 2007F (Burke) Note

        The Series 2007F (Burke) Note and the Trustee's certificate of authentication for the Series 2007F (Burke) Note shall be substantially in the form of Exhibit I attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

I.

The Series 2007A (Monroe) Note

        The Series 2007A (Monroe) Note and the Trustee's certificate of authentication for the Series 2007A (Monroe) Note shall be substantially in the form of Exhibit J attached hereto, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted in the Original Indenture.

ARTICLE II

MISCELLANEOUS

Section 2.1    This Forty-First Supplemental Indenture is executed and shall be construed as an indenture supplemental to the Original Indenture, and shall form a part thereof, and the Original Indenture, as heretofore supplemented and as hereby supplemented and modified, is hereby confirmed. Except to the extent inconsistent with the express terms hereof, all of the provisions, terms, covenants and conditions of the Indenture shall be applicable to the Notes to the same extent as if specifically set forth herein. All references herein to Sections, definitions or other provisions of the Original Indenture shall be to such Sections, definitions and other provisions as they may be amended or modified from time to time pursuant to the Indenture. All capitalized terms used in this Forty-First Supplemental Indenture shall have the same meanings assigned to them in the Original Indenture, except in cases where the context clearly indicates otherwise.

Section 2.2    All recitals in this Forty-First Supplemental Indenture are made by the Company only and not by the Trustee; and all of the provisions contained in the Original Indenture, in respect of the rights, privileges, immunities, powers and duties of the Trustee shall be applicable in respect hereof as fully and with like effect as if set forth herein in full.

Section 2.3    Whenever in this Forty-First Supplemental Indenture any of the parties hereto is named or referred to, this shall, subject to the provisions of Articles IX and XI of the Original Indenture, be deemed to include the successors and assigns of such party, and all the covenants and agreements in

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this Forty-First Supplemental Indenture contained by or on behalf of the Company, or by or on behalf of the Trustee shall, subject as aforesaid, bind and inure to the respective benefits of the respective successors and assigns of such parties, whether so expressed or not.

Section 2.4    Nothing in this Forty-First Supplemental Indenture, expressed or implied, is intended, or shall be construed, to confer upon, or to give to, any person, firm or corporation, other than the parties hereto and the Holders of the Outstanding Secured Obligations, any right, remedy or claim under or by reason of this Forty-First Supplemental Indenture or any covenant, condition, stipulation, promise or agreement hereof, and all the covenants, conditions, stipulations, promises and agreements in this Forty-First Supplemental Indenture contained by or on behalf of the Company shall be for the sole and exclusive benefit of the parties hereto, and of the Holders of Outstanding Secured Obligations.

Section 2.5    This Forty-First Supplemental Indenture may be executed in several counterparts, each of such counterparts shall for all purposes be deemed to be an original, and all such counterparts, or as many of them as the Company and the Trustee shall preserve undestroyed, shall together constitute but one and the same instrument.

Section 2.6    To the extent permitted by applicable law, this Forty-First Supplemental Indenture shall be deemed to be a Security Agreement and Financing Statement whereby the Company grants to the Trustee a security interest in all of the Trust Estate that is personal property or fixtures under the Uniform Commercial Code, as adopted or hereafter adopted in one or more of the states in which any part of the properties of the Company are situated. The mailing address of the Company, as debtor is:

2100 East Exchange Place
Tucker, Georgia 30084-5336,

and the mailing address of the Trustee, as secured party, is:

U.S. Bank National Association
Attention: Corporate Trust Services
1349 West Peachtree Street, NW
Suite 1050, Two Midtown Plaza
Atlanta, Georgia 30309

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IN WITNESS WHEREOF, the parties hereto have caused this Forty-First Supplemental Indenture to be duly executed under seal as of the day and year first written above.

Company:	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION), an electric membership corporation organized under the laws of the State of Georgia
	By:	/s/ Elizabeth B. Higgins Elizabeth B. Higgins Chief Financial Officer
Signed, sealed and delivered by the Company in the presence of:	Attest:	/s/ Patricia N. Nash Patricia N. Nash Secretary
/s/ Michelle Hanus	[CORPORATE SEAL]
Witness
/s/ Thomas J. Brendiar
Notary Public
(Notarial Seal)
My commission expires:     1/27/09

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Trustee:	U.S. BANK NATIONAL ASSOCIATION, a national banking association
Signed and delivered by the Trustee in the Presence of:	By:	/s/ Jack Ellerin Authorized Agent
/s/ Sonia S. Henry
Witness
/s/ Muriel Shaw
Notary Public
(Notarial Seal)
My commission expires:     1/14/08

Exhibit A

        All property of the Company in the Counties in Appling, Ben Hill, Burke, Carroll, Clarke, Cobb, DeKalb, Floyd, Heard, Jackson, Monroe, Talbot and Toombs, State of Georgia.

A-1

Exhibit B

[Form of Series 2007A (Appling) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF APPLING COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007A (APPLING) NOTE                DATE: OCTOBER 25, 2007

(HATCH PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Appling County (the "Appling Authority") to issue $20,530,000 in aggregate principal amount of Development Authority of Appling County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Hatch Project), Series 2007A (the "Series 2007A Appling Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007A Appling Trustee"), as assignee and pledgee of the Appling Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Appling Authority to the Series 2007A Appling Trustee (the "Series 2007A (Appling) Indenture"), or its successor in trust, the principal sum of $20,530,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007A Indenture), a sum which will equal the interest on the Series 2007A Appling Bonds which will become due on such Interest Payment Date on the Series 2007A Appling Bonds; and

        (b)   on or before January 1, 2038, a sum which will equal the principal amount of the Series 2007A Appling Bonds which will become due on January 1, 2038; and

        (c)   on or before any redemption date for the Series 2007A Appling Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007A Appling Bonds which are to be redeemed on such date.

        This Series 2007A (Appling) Note evidences the Loan (as defined in the Series 2007A (Appling) Loan Agreement hereinafter referred to) of the Appling Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007A (Appling) Loan Agreement"), between the Appling Authority and Oglethorpe, pursuant to which the Appling Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007A Appling Bonds.

        This Series 2007A (Appling) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007A (Appling) Note and of the terms upon which this Series 2007A (Appling) Note is authenticated and

B-1

delivered. This Series 2007A (Appling) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007A (Appling) Note."

        All payments hereon are to be made to the Series 2007A Appling Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007A (Appling) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007A (Appling) Loan Agreement.

        This Series 2007A (Appling) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007A (Appling) Loan Agreement.

        If the Series 2007A Appling Trustee shall accelerate payment of the Series 2007A Appling Bonds, all payments on this Series 2007A (Appling) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007A (Appling) Loan Agreement. The Series 2007A (Appling) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007A Appling Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007A (Appling) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007A (Appling) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007A (Appling) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

B-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007A (Appling) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

B-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

B-4

Exhibit C

[Form of Series 2007B (Appling) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF APPLING COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007B (APPLING) NOTE                DATE: OCTOBER 25, 2007

(HATCH PROJECT)

OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Appling County (the "Appling Authority") to issue $20,000,000 in aggregate principal amount of Development Authority of Appling County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Hatch Project), Series 2007B (the "Series 2007B Appling Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007B Appling Trustee"), as assignee and pledgee of the Appling Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Appling Authority to the Series 2007B Appling Trustee (the "Series 2007B (Appling) Indenture"), or its successor in trust, the principal sum of $20,000,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007B Indenture), a sum which will equal the interest on the Series 2007B Appling Bonds which will become due on such Interest Payment Date on the Series 2007B Appling Bonds; and

        (b)   on or before January 1, 2038, a sum which will equal the principal amount of the Series 2007B Appling Bonds which will become due on January 1, 2038; and

        (c)   on or before any redemption date for the Series 2007B Appling Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007B Appling Bonds which are to be redeemed on such date.

        This Series 2007B (Appling) Note evidences the Loan (as defined in the Series 2007B (Appling) Loan Agreement hereinafter referred to) of the Appling Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007B (Appling) Loan Agreement"), between the Appling Authority and Oglethorpe, pursuant to which the Appling Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007B Appling Bonds.

        This Series 2007B (Appling) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007B (Appling) Note and of the terms upon which this Series 2007B (Appling) Note is authenticated and

C-1

delivered. This Series 2007B (Appling) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007B (Appling) Note."

        All payments hereon are to be made to the Series 2007B Appling Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007B (Appling) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007B (Appling) Loan Agreement.

        This Series 2007B (Appling) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007B (Appling) Loan Agreement.

        If the Series 2007B Appling Trustee shall accelerate payment of the Series 2007B Appling Bonds, all payments on this Series 2007B (Appling) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007B (Appling) Loan Agreement. The Series 2007B (Appling) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007B Appling Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007B (Appling) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007B (Appling) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007B (Appling) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

C-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007B (Appling) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

C-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

C-4

Exhibit D

[Form of Series 2007A (Burke) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF BURKE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007A (BURKE) NOTE                DATE: OCTOBER 25, 2007

(VOGTLE PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Burke County (the "Burke Authority") to issue $27,105,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007A (the "Series 2007A Burke Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007A Burke Trustee"), as assignee and pledgee of the Burke Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Burke Authority to the Series 2007A Burke Trustee (the "Series 2007A (Burke) Indenture"), or its successor in trust, the principal sum of $27,105,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007A Indenture), a sum which will equal the interest on the Series 2007A Burke Bonds which will become due on such Interest Payment Date on the Series 2007A Burke Bonds; and

        (b)   on or before January 1, 2039, a sum which will equal the principal amount of the Series 2007A Burke Bonds which will become due on January 1, 2039; and

        (c)   on or before any redemption date for the Series 2007A Burke Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007A Burke Bonds which are to be redeemed on such date.

        This Series 2007A (Burke) Note evidences the Loan (as defined in the Series 2007A (Burke) Loan Agreement hereinafter referred to) of the Burke Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007A (Burke) Loan Agreement"), between the Burke Authority and Oglethorpe, pursuant to which the Burke Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007A Burke Bonds.

        This Series 2007A (Burke) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007A (Burke) Note and of the terms upon which this Series 2007A (Burke) Note is authenticated and

D-1

delivered. This Series 2007A (Burke) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007A (Burke) Note."

        All payments hereon are to be made to the Series 2007A Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007A (Burke) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007A (Burke) Loan Agreement.

        This Series 2007A (Burke) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007A (Burke) Loan Agreement.

        If the Series 2007A Burke Trustee shall accelerate payment of the Series 2007A Burke Bonds, all payments on this Series 2007A (Burke) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007A (Burke) Loan Agreement. The Series 2007A (Burke) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007A Burke Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007A (Burke) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007A (Burke) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

D-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007A (Burke) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

D-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

D-4

Exhibit E

[Form of Series 2007B (Burke) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF BURKE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007B (BURKE) NOTE                DATE: OCTOBER 25, 2007

(VOGTLE PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Burke County (the "Burke Authority") to issue $27,210,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007B (the "Series 2007B Burke Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007B Burke Trustee"), as assignee and pledgee of the Burke Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Burke Authority to the Series 2007B Burke Trustee (the "Series 2007B (Burke) Indenture"), or its successor in trust, the principal sum of $27,210,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007B Indenture), a sum which will equal the interest on the Series 2007B Burke Bonds which will become due on such Interest Payment Date on the Series 2007B Burke Bonds; and

        (b)   on or before January 1, 2038, a sum which will equal the principal amount of the Series 2007B Burke Bonds which will become due on January 1, 2038; and

        (c)   on or before any redemption date for the Series 2007B Burke Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007B Burke Bonds which are to be redeemed on such date.

        This Series 2007B (Burke) Note evidences the Loan (as defined in the Series 2007B (Burke) Loan Agreement hereinafter referred to) of the Burke Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007B (Burke) Loan Agreement"), between the Burke Authority and Oglethorpe, pursuant to which the Burke Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007B Burke Bonds.

        This Series 2007B (Burke) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007B (Burke) Note and of the terms upon which this Series 2007B (Burke) Note is authenticated and

E-1

delivered. This Series 2007B (Burke) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007B (Burke) Note."

        All payments hereon are to be made to the Series 2007B Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007B (Burke) Loan Agreement.

        This Series 2007B (Burke) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007B (Burke) Loan Agreement.

        If the Series 2007B Burke Trustee shall accelerate payment of the Series 2007B Burke Bonds, all payments on this Series 2007B (Burke) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007B (Burke) Loan Agreement. The Series 2007B (Burke) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007B Burke Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007B (Burke) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007B (Burke) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007B (Burke) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

E-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007B (Burke) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

E-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

E-4

Exhibit F

[Form of Series 2007C (Burke) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF BURKE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007C (BURKE) NOTE                DATE: OCTOBER 25, 2007

(VOGTLE PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Burke County (the "Burke Authority") to issue $20,000,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007C (the "Series 2007C Burke Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007C Burke Trustee"), as assignee and pledgee of the Burke Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Burke Authority to the Series 2007C Burke Trustee (the "Series 2007C (Burke) Indenture"), or its successor in trust, the principal sum of $20,000,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007C Indenture), a sum which will equal the interest on the Series 2007C Burke Bonds which will become due on such Interest Payment Date on the Series 2007C Burke Bonds; and

        (b)   on or before January 1, 2039, a sum which will equal the principal amount of the Series 2007C Burke Bonds which will become due on January 1, 2039; and

        (c)   on or before any redemption date for the Series 2007C Burke Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007C Burke Bonds which are to be redeemed on such date.

        This Series 2007C (Burke) Note evidences the Loan (as defined in the Series 2007C (Burke) Loan Agreement hereinafter referred to) of the Burke Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007C (Burke) Loan Agreement"), between the Burke Authority and Oglethorpe, pursuant to which the Burke Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007C Burke Bonds.

        This Series 2007C (Burke) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007C (Burke) Note and of the terms upon which this Series 2007C (Burke) Note is authenticated and

F-1

delivered. This Series 2007C (Burke) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007C (Burke) Note."

        All payments hereon are to be made to the Series 2007C Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007C (Burke) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007C (Burke) Loan Agreement.

        This Series 2007C (Burke) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007C (Burke) Loan Agreement.

        If the Series 2007C Burke Trustee shall accelerate payment of the Series 2007C Burke Bonds, all payments on this Series 2007C (Burke) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007C (Burke) Loan Agreement. The Series 2007C (Burke) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007C Burke Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007C (Burke) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007C (Burke) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007C (Burke) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

F-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007C (Burke) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

F-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

F-4

Exhibit G

[Form of Series 2007D (Burke) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF BURKE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007D (BURKE) NOTE                DATE: OCTOBER 25, 2007

(VOGTLE PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Burke County (the "Burke Authority") to issue $20,000,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007D (the "Series 2007D Burke Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007D Burke Trustee"), as assignee and pledgee of the Burke Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Burke Authority to the Series 2007D Burke Trustee (the "Series 2007D (Burke) Indenture"), or its successor in trust, the principal sum of $20,000,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007D Indenture), a sum which will equal the interest on the Series 2007D Burke Bonds which will become due on such Interest Payment Date on the Series 2007D Burke Bonds; and

        (b)   on or before January 1, 2040, a sum which will equal the principal amount of the Series 2007D Burke Bonds which will become due on January 1, 2040; and

        (c)   on or before any redemption date for the Series 2007D Burke Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007D Burke Bonds which are to be redeemed on such date.

        This Series 2007D (Burke) Note evidences the Loan (as defined in the Series 2007D (Burke) Loan Agreement hereinafter referred to) of the Burke Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007D (Burke) Loan Agreement"), between the Burke Authority and Oglethorpe, pursuant to which the Burke Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007D Burke Bonds.

        This Series 2007D (Burke) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007D (Burke) Note and of the terms upon which this Series 2007D (Burke) Note is authenticated and

G-1

delivered. This Series 2007D (Burke) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007D (Burke) Note."

        All payments hereon are to be made to the Series 2007D Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007D (Burke) Loan Agreement.

        This Series 2007D (Burke) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007D (Burke) Loan Agreement.

        If the Series 2007D Burke Trustee shall accelerate payment of the Series 2007D Burke Bonds, all payments on this Series 2007D (Burke) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007D (Burke) Loan Agreement. The Series 2007D (Burke) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007D Burke Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007D (Burke) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007D (Burke) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007D (Burke) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

G-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007D (Burke) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

G-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

G-4

Exhibit H

[Form of Series 2007E (Burke) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF BURKE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007E (BURKE) NOTE                DATE: OCTOBER 25, 2007

(VOGTLE PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Burke County (the "Burke Authority") to issue $20,000,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007E (the "Series 2007E Burke Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007E Burke Trustee"), as assignee and pledgee of the Burke Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Burke Authority to the Series 2007E Burke Trustee (the "Series 2007E (Burke) Indenture"), or its successor in trust, the principal sum of $20,000,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007E Indenture), a sum which will equal the interest on the Series 2007E Burke Bonds which will become due on such Interest Payment Date on the Series 2007E Burke Bonds; and

        (b)   on or before January 1, 2040, a sum which will equal the principal amount of the Series 2007E Burke Bonds which will become due on January 1, 2040; and

        (c)   on or before any redemption date for the Series 2007E Burke Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007E Burke Bonds which are to be redeemed on such date.

        This Series 2007E (Burke) Note evidences the Loan (as defined in the Series 2007E (Burke) Loan Agreement hereinafter referred to) of the Burke Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007E (Burke) Loan Agreement"), between the Burke Authority and Oglethorpe, pursuant to which the Burke Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007E Burke Bonds.

        This Series 2007E (Burke) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007E (Burke) Note and of the terms upon which this Series 2007E (Burke) Note is authenticated and

H-1

delivered. This Series 2007E (Burke) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007E (Burke) Note."

        All payments hereon are to be made to the Series 2007E Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007E (Burke) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007E (Burke) Loan Agreement.

        This Series 2007E (Burke) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007E (Burke) Loan Agreement.

        If the Series 2007E Burke Trustee shall accelerate payment of the Series 2007E Burke Bonds, all payments on this Series 2007E (Burke) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007E (Burke) Loan Agreement. The Series 2007E (Burke) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007E Burke Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007E (Burke) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007E (Burke) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007E (Burke) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

H-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007E (Burke) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

H-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

H-4

Exhibit I

[Form of Series 2007F (Burke) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF BURKE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007F (BURKE) NOTE                DATE: OCTOBER 25, 2007

(VOGTLE PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Burke County (the "Burke Authority") to issue $10,390,000 in aggregate principal amount of Development Authority of Burke County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Vogtle Project), Series 2007F (the "Series 2007F Burke Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007F Burke Trustee"), as assignee and pledgee of the Burke Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Burke Authority to the Series 2007F Burke Trustee (the "Series 2007F (Burke) Indenture"), or its successor in trust, the principal sum of $10,390,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007F Indenture), a sum which will equal the interest on the Series 2007F Burke Bonds which will become due on such Interest Payment Date on the Series 2007F Burke Bonds; and

        (b)   on or before January 1, 2039, a sum which will equal the principal amount of the Series 2007F Burke Bonds which will become due on January 1, 2039; and

        (c)   on or before any redemption date for the Series 2007F Burke Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007F Burke Bonds which are to be redeemed on such date.

        This Series 2007F (Burke) Note evidences the Loan (as defined in the Series 2007F (Burke) Loan Agreement hereinafter referred to) of the Burke Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007F (Burke) Loan Agreement"), between the Burke Authority and Oglethorpe, pursuant to which the Burke Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007F Burke Bonds.

        This Series 2007F (Burke) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007F (Burke) Note and of the terms upon which this Series 2007F (Burke) Note is authenticated and

I-1

delivered. This Series 2007F (Burke) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007F (Burke) Note."

        All payments hereon are to be made to the Series 2007F Burke Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007F (Burke) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007F (Burke) Loan Agreement.

        This Series 2007F (Burke) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007F (Burke) Loan Agreement.

        If the Series 2007F Burke Trustee shall accelerate payment of the Series 2007F Burke Bonds, all payments on this Series 2007F (Burke) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007F (Burke) Loan Agreement. The Series 2007F (Burke) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007F Burke Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007F (Burke) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007F (Burke) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007F (Burke) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

I-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007F (Burke) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

I-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

I-4

Exhibit J

[Form of Series 2007A (Monroe) Note]

THIS NOTE IS NON-TRANSFERABLE EXCEPT AS MAY BE REQUIRED TO EFFECT ANY TRANSFER TO ANY SUCCESSOR TRUSTEE UNDER THE TRUST INDENTURE, DATED AS OF OCTOBER 1, 2007, RELATING HERETO, BETWEEN THE DEVELOPMENT AUTHORITY OF MONROE COUNTY AND U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE.

OGLETHORPE POWER CORPORATION
(AN ELECTRIC MEMBERSHIP CORPORATION)

SERIES 2007A (MONROE) NOTE                DATE: OCTOBER 25, 2007

(SCHERER PROJECT)

        OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION) ("Oglethorpe"), an electric membership corporation organized and existing under the laws of the State of Georgia, for value received and in consideration of the agreement of the Development Authority of Monroe County (the "Monroe Authority") to issue $16,655,000 in aggregate principal amount of Development Authority of Monroe County Pollution Control Revenue Bonds (Oglethorpe Power Corporation Scherer Project), Series 2007A (the "Series 2007A Monroe Bonds") and to loan the proceeds thereof to Oglethorpe, hereby promises to pay to U.S. Bank National Association (the "Series 2007A Monroe Trustee"), as assignee and pledgee of the Monroe Authority, acting pursuant to the Trust Indenture, dated as of October 1, 2007, from the Monroe Authority to the Series 2007A Monroe Trustee (the "Series 2007A (Monroe) Indenture"), or its successor in trust, the principal sum of $16,655,000, together with interest and prepayment premium (if any) thereon as follows:

        (a)   on or before each Interest Payment Date (as defined in the Series 2007A Indenture), a sum which will equal the interest on the Series 2007A Monroe Bonds which will become due on such Interest Payment Date on the Series 2007A Monroe Bonds; and

        (b)   on or before January 1, 2038, a sum which will equal the principal amount of the Series 2007A Monroe Bonds which will become due on January 1, 2038; and

        (c)   on or before any redemption date for the Series 2007A Monroe Bonds, a sum equal to the principal of, redemption premium (if any) and interest on, the Series 2007A Monroe Bonds which are to be redeemed on such date.

        This Series 2007A (Monroe) Note evidences the Loan (as defined in the Series 2007A (Monroe) Loan Agreement hereinafter referred to) of the Monroe Authority to Oglethorpe and the obligation to repay the same and shall be governed by and shall be payable in accordance with the terms, conditions and provisions of the Loan Agreement, dated as of October 1, 2007 (the "Series 2007A (Monroe) Loan Agreement"), between the Monroe Authority and Oglethorpe, pursuant to which the Monroe Authority has agreed to loan to Oglethorpe the proceeds from the sale of the Series 2007A Monroe Bonds.

        This Series 2007A (Monroe) Note is a duly authorized obligation of Oglethorpe issued under and equally and ratably secured by the Indenture, dated as of March 1, 1997 (the "Original Indenture"), as heretofore supplemented and as supplemented by the Forty-First Supplemental Indenture, dated as of October 1, 2007, between Oglethorpe, as grantor, and U.S. Bank National Association, as successor to SunTrust Bank, formerly known as SunTrust Bank, Atlanta, as trustee (in such capacity, the "Indenture Trustee"), (the Original Indenture, as supplemented, the "Indenture"). Reference is hereby made to the Indenture for a statement of the description of the properties thereby mortgaged, pledged and assigned, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities thereunder of Oglethorpe, the Indenture Trustee and the holder of this Series 2007A (Monroe) Note and of the terms upon which this Series 2007A (Monroe) Note is authenticated and

J-1

delivered. This Series 2007A (Monroe) Note is created by the Forty-First Supplemental Indenture and designated as the "Series 2007A (Monroe) Note."

        All payments hereon are to be made to the Series 2007A Monroe Trustee at its corporate office in Atlanta, Georgia, in lawful money of the United States of America which will be immediately available on the day payment is due. As set forth in Section 4.6 of the Series 2007A (Monroe) Loan Agreement, the obligation of Oglethorpe to make the payments required hereunder shall be absolute and unconditional.

        Oglethorpe shall be entitled to certain credits against payments required to be made hereunder as provided in Section 4.3 of the Series 2007A (Monroe) Loan Agreement.

        This Series 2007A (Monroe) Note may be prepaid upon the terms and conditions set forth in Article VIII of the Series 2007A (Monroe) Loan Agreement.

        If the Series 2007A Monroe Trustee shall accelerate payment of the Series 2007A Monroe Bonds, all payments on this Series 2007A (Monroe) Note shall be declared due and payable in the manner and with the effect provided in the Series 2007A (Monroe) Loan Agreement. The Series 2007A (Monroe) Loan Agreement provides that, under certain conditions, such declaration shall be rescinded by the Series 2007A Monroe Trustee.

        No recourse shall be had for the payments required hereby or for any claim based herein or in the Series 2007A (Monroe) Loan Agreement or in the Indenture against any officer, director or member, past, present or future, of Oglethorpe as such, either directly or through Oglethorpe, or under any constitutional provision, statute or rule of law or by the enforcement of any assessment or by any legal or equitable proceedings or otherwise.

        This Series 2007A (Monroe) Note shall not be entitled to any benefit under the Indenture and shall not become valid or obligatory for any purposes until the Indenture Trustee shall have signed the form of authentication certificate endorsed hereon.

        This Series 2007A (Monroe) Note shall be governed by and construed in accordance with the laws of the State of Georgia.

J-2

IN WITNESS WHEREOF, Oglethorpe has caused this Series 2007A (Monroe) Note to be executed in its corporate name by its President and Chief Executive Officer and attested by its Secretary and its corporate seal to be hereunto affixed.

	OGLETHORPE POWER CORPORATION (AN ELECTRIC MEMBERSHIP CORPORATION)
	By:
		Elizabeth B. Higgins Chief Financial Officer
(SEAL)
Attest:
Patricia N. Nash Secretary

J-3

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Obligations of the series designated therein referred to in the within mentioned Indenture.

U.S. BANK NATIONAL ASSOCIATION, as Trustee
By:
	Authorized Agent

J-4

Schedule 1

RECORDING INFORMATION
FOR
                COUNTY, GEORGIA

DOCUMENT	RECORDING INFORMATION	DATE OF RECORDING
Original Indenture
First Supplemental Indenture
Second Supplemental Indenture
Third Supplemental Indenture
Fourth Supplemental Indenture
Fifth Supplemental Indenture
Sixth Supplemental Indenture
Seventh Supplemental Indenture
Eighth Supplemental Indenture
Ninth Supplemental Indenture
Tenth Supplemental Indenture
Eleventh Supplemental Indenture
Twelfth Supplemental Indenture
Thirteenth Supplemental Indenture
Fourteenth Supplemental Indenture
Fifteenth Supplemental Indenture
Sixteenth Supplemental Indenture
Seventeenth Supplemental Indenture
Eighteenth Supplemental Indenture
Nineteenth Supplemental Indenture
Twentieth Supplemental Indenture
Twenty-First Supplemental Indenture
Twenty-Second Supplemental Indenture
Twenty-Third Supplemental Indenture
Twenty-Fourth Supplemental Indenture
Twenty-Fifth Supplemental Indenture
Twenty-Sixth Supplemental Indenture
Twenty-Seventh Supplemental Indenture
Twenty-Eighth Supplemental Indenture
Twenty-Ninth Supplemental Indenture
Thirtieth Supplemental Indenture
Thirty-First Supplemental Indenture
Thirty-Second Supplemental Indenture
Thirty-Third Supplemental Indenture
Thirty-Fourth Supplemental Indenture
Thirty-Fifth Supplemental Indenture
Thirty-Sixth Supplemental Indenture
Thirty-Seventh Supplemental Indenture
Thirty-Eighth Supplemental Indenture
Thirty-Ninth Supplemental Indenture
Fortieth Supplemental Indenture

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FORTY-FIRST SUPPLEMENTAL INDENTURE

EX-31.1

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EXHIBIT 31.1

Rule 13a-14(a)/15d-14(a) Certification, by Thomas A. Smith
(Principal Executive Officer)

I, Thomas A. Smith, certify that:

1.

I have reviewed this quarterly report on Form 10-Q of Oglethorpe Power Corporation (An Electric Membership Corporation);



2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;



3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;



4.

The registrant's other certifying officers and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:



(a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;



(b)

Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and



(c)

Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and



5.

The registrant's other certifying officers and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of registrant's board of directors (or persons performing the equivalent functions):



(a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and



(b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: November 13, 2007

/s/ Thomas A. Smith Thomas A. Smith
President and Chief Executive Officer
(Principal Executive Officer)

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Rule 13a-14(a)/15d-14(a) Certification, by Thomas A. Smith (Principal Executive Officer)

EX-31.2

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EXHIBIT 31.2

Rule 13a-14(a)/15d-14(a) Certification, by Elizabeth B. Higgins
(Principal Financial Officer)

I, Elizabeth B. Higgins, certify that:

1.

I have reviewed this quarterly report on Form 10-Q of Oglethorpe Power Corporation (An Electric Membership Corporation);



2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;



3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;



4.

The registrant's other certifying officers and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:



(a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;



(b)

Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and



(c)

Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and



5.

The registrant's other certifying officers and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of registrant's board of directors (or persons performing the equivalent functions):



(a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and



(b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: November 13, 2007

/s/ Elizabeth B. Higgins Elizabeth B. Higgins
Chief Financial Officer
(Principal Financial Officer)

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Rule 13a-14(a)/15d-14(a) Certification, by Elizabeth B. Higgins (Principal Financial Officer)

EX-32.1

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EXHIBIT 32.1

Certification Pursuant to 18 U.S.C. 1350
As Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

        In connection with the Quarterly Report on Form 10-Q for the period ended September 30, 2007 (the "Report") of Oglethorpe Power Corporation (the "Registrant"), as filed with the Securities and Exchange Commission on the date hereof, I, Thomas A. Smith, the President and Chief Executive Officer of the Registrant certify, to the best of my knowledge, that:

(1)

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and



(2)

The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

/s/ Thomas A. Smith Thomas A. Smith
President and Chief Executive Officer

November 13, 2007 Date

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EXHIBIT 32.1

EX-32.2

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EXHIBIT 32.2

Certification Pursuant to 18 U.S.C. 1350
As Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

        In connection with the Quarterly Report on Form 10-Q for the period ended September 30, 2007 (the "Report") of Oglethorpe Power Corporation (the "Registrant"), as filed with the Securities and Exchange Commission on the date hereof, I, Elizabeth B. Higgins, the Chief Financial Officer of the Registrant certify, to the best of my knowledge, that:

(1)

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and



(2)

The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

/s/ Elizabeth B. Higgins Elizabeth B. Higgins
Chief Financial Officer

November 13, 2007 Elizabeth B. Higgins
Date

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EXHIBIT 32.2