Consolidated Balance Sheets (Unaudited) (USD $) In Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2011		Dec. 31, 2010
Current assets
Cash and cash equivalents	$ 562		$ 1,612
Restricted cash and investments	35		30
Accounts receivable, net
Customer	1,766		1,932
Other	697		1,196
Mark-to-market derivative assets	438		487
Mark-to-market derivative assets with affiliates	0		0
Inventories, net
Fossil fuel	161		216
Materials and supplies	625		590
Deferred income taxes	69		0
Regulatory assets	125		10
Other	509		325
Total current assets	4,987		6,398
Property, plant and equipment, net	30,856		29,941
Deferred debits and other assets
Regulatory assets	4,189		4,140
Nuclear decommissioning trust funds	6,699		6,408
Investments	736		717
Investments in affiliates	15		15
Goodwill	2,625		2,625
Mark-to-market derivative assets	324		409
Mark-to-market derivative assets with affiliates	0		0
Pledged assets for Zion Station decommissioning	804		824
Other	751		763
Total deferred debits and other assets	16,143		15,901
Total assets	51,986		52,240
Current liabilities
Short-term borrowings	140		0
Short-term notes payable - accounts receivable agreement	225		225
Long-term debt due within one year	1,048		599
Accounts payable	1,297		1,373
Accrued expenses	878		1,040
Deferred income taxes	0		85
Regulatory liabilities	63		44
Mark-to-market derivative liabilities	50		38
Mark-to-market derivative liabilities with affiliate	0		0
Other	567		836
Total current liabilities	4,268		4,240
Long-term debt	11,764		11,614
Long-term debt to financing trusts	390		390
Deferred credits and other liabilities
Deferred income taxes and unamortized investment tax credits	7,391		6,621
Asset retirement obligations	3,597		3,494
Pension obligations	1,495		3,658
Non-pension postretirement benefit obligations	2,311		2,218
Spent nuclear fuel obligation	1,019		1,018
Regulatory liabilities	3,706		3,555
Mark-to-market derivative liabilities	66		21
Mark-to-market derivative liabilities with affiliate	0		0
Payable for Zion Station decommissioning	640		659
Other	1,137		1,102
Total deferred credits and other liabilities	21,362		22,346
Total liabilities	37,784		38,590
Commitments and contingencies	-		-
Preferred securities	87		87
Shareholders' equity
Common stock	9,054		9,006
Treasury stock, at cost (35 and 35 shares held at December 31, 2010 and December 31, 2009, respectively)	(2,327)		(2,327)
Retained earnings	9,894		9,304
Accumulated other comprehensive income (loss), net	(2,509)		(2,423)
Total shareholders' equity	14,112		13,560
Noncontrolling interest	3		3
Total equity	14,115		13,563
Total liabilities and shareholders' equity	51,986		52,240
Member's equity
Accumulated other comprehensive income (loss), net	(2,509)		(2,423)
Noncontrolling interest	3		3
Exelon Generation Co L L C [Member]
Current assets
Cash and cash equivalents	109		456
Restricted cash and cash equivalents	1		1
Accounts receivable, net
Customer	582		469
Other	200		161
Mark-to-market derivative assets	438	[1]	487	[2]
Mark-to-market derivative assets with affiliates	414	[1]	455	[2]
Receivables from affiliates	86		306
Inventories, net
Fossil fuel	104		129
Materials and supplies	527		500
Other	215		123
Total current assets	2,676		3,087
Property, plant and equipment, net	12,224		11,662
Deferred debits and other assets
Nuclear decommissioning trust funds	6,699		6,408
Investments	38		35
Mark-to-market derivative assets	310	[1]	391	[2]
Mark-to-market derivative assets with affiliates	345	[1]	525	[2]
Prepaid pension asset	2,127		1,236
Pledged assets for Zion Station decommissioning	804		824
Other	410		366
Total deferred debits and other assets	10,733		9,785
Total assets	25,633		24,534
Current liabilities
Long-term debt due within one year	3		3
Accounts payable	670		749
Accrued expenses	562		391
Payables to affiliates	51		47
Deferred income taxes	216		427
Mark-to-market derivative liabilities	47	[1]	34	[2]
Mark-to-market derivative liabilities with affiliate	0	[1]	0	[2]
Other	198		192
Total current liabilities	1,747		1,843
Long-term debt	3,675		3,676
Deferred credits and other liabilities
Deferred income taxes and unamortized investment tax credits	3,616		3,318
Asset retirement obligations	3,458		3,357
Non-pension postretirement benefit obligations	756		692
Spent nuclear fuel obligation	1,019		1,018
Payables to affiliates	2,380		2,267
Mark-to-market derivative liabilities	36	[1]	21	[2]
Mark-to-market derivative liabilities with affiliate	0	[1]	0	[2]
Payable for Zion Station decommissioning	640		659
Other	514		506
Total deferred credits and other liabilities	12,419		11,838
Total liabilities	17,841		17,357
Commitments and contingencies	-		-
Shareholders' equity
Accumulated other comprehensive income (loss), net	690		1,013
Noncontrolling interest	5		5
Member's equity
Membership interest	3,526		3,526
Undistributed earnings	3,571		2,633
Accumulated other comprehensive income (loss), net	690		1,013
Total member's equity	7,787		7,172
Noncontrolling interest	5		5
Total equity	7,792		7,177
Total liabilities and equity	25,633		24,534
Commonwealth Edison Co [Member]
Current assets
Cash and cash equivalents	94		50
Restricted cash and cash equivalents	3		0
Accounts receivable, net
Customer	748		768
Other	287		525
Inventories, net
Inventories, net	79		72
Deferred income taxes	40		115
Counterparty collateral deposited	125		153
Regulatory assets	505		456
Other	20		12
Total current assets	1,901		2,151
Property, plant and equipment, net	12,824		12,578
Deferred debits and other assets
Regulatory assets	822		947
Investments	22		23
Investments in affiliates	6		6
Goodwill	2,625		2,625
Receivable from affiliate	1,981		1,895
Mark-to-market derivative assets	0		4
Prepaid pension asset	1,856		1,039
Other	311		384
Total deferred debits and other assets	7,623		6,923
Total assets	22,348		21,652
Current liabilities
Short-term borrowings	0		0
Long-term debt due within one year	796		347
Accounts payable	303		332
Accrued expenses	260		366
Payables to affiliates	374		398
Customer deposits	133		130
Regulatory liabilities	23		19
Mark-to-market derivative liabilities with affiliate	412		450
Other	107		92
Total current liabilities	2,408		2,134
Long-term debt	4,805		4,654
Long-term debt to financing trusts	206		206
Deferred credits and other liabilities
Deferred income taxes and unamortized investment tax credits	3,461		3,308
Asset retirement obligations	106		105
Non-pension postretirement benefit obligations	324		271
Regulatory liabilities	3,250		3,137
Mark-to-market derivative liabilities	30
Mark-to-market derivative liabilities with affiliate	345		525
Other	470		402
Total deferred credits and other liabilities	7,986		7,748
Total liabilities	15,405		14,742
Commitments and contingencies	-		-
Shareholders' equity
Common stock	1,588		1,588
Other paid-in capital	4,992		4,992
Retained earnings	364		331
Accumulated other comprehensive income (loss), net	(1)		(1)
Total shareholders' equity	6,943		6,910
Total liabilities and shareholders' equity	22,348		21,652
Member's equity
Accumulated other comprehensive income (loss), net	(1)		(1)
PECO Energy Co [Member]
Current assets
Cash and cash equivalents	319		522
Restricted cash and cash equivalents	2		0
Accounts receivable, net
Customer	435		695
Other	199		277
Inventories, net
Fossil fuel	57		87
Materials and supplies	19		18
Deferred income taxes	41		41
Receivable from Exelon intercompany money pool	171		0
Prepaid utility taxes	92		0
Regulatory assets	34		9
Other	35		21
Total current assets	1,404		1,670
Property, plant and equipment, net	5,730		5,620
Deferred debits and other assets
Regulatory assets	1,010		968
Investments	22		20
Investments in affiliates	8		8
Receivable from affiliate	401		375
Prepaid pension asset	386		281
Other	35		43
Total deferred debits and other assets	1,862		1,695
Total assets	8,996		8,985
Current liabilities
Short-term notes payable - accounts receivable agreement	225		225
Long-term debt due within one year	250		250
Accounts payable	244		201
Accrued expenses	77		95
Payables to affiliates	57		275
Customer deposits	55		65
Regulatory liabilities	40		25
Mark-to-market derivative liabilities	2		4
Mark-to-market derivative liabilities with affiliate	2		5
Other	22		18
Total current liabilities	974		1,163
Long-term debt	1,972		1,972
Long-term debt to financing trusts	184		184
Deferred credits and other liabilities
Deferred income taxes and unamortized investment tax credits	1,947		1,823
Asset retirement obligations	33		32
Non-pension postretirement benefit obligations	304		292
Regulatory liabilities	457		418
Other	131		131
Total deferred credits and other liabilities	2,872		2,696
Total liabilities	6,002		6,015
Commitments and contingencies	-		-
Preferred securities	87		87
Shareholders' equity
Common stock	2,361		2,361
Retained earnings	546		522
Accumulated other comprehensive income (loss), net	0		0
Total shareholders' equity	2,907		2,883
Total liabilities and shareholders' equity	8,996		8,985
Member's equity
Accumulated other comprehensive income (loss), net	$ 0		$ 0

[1] Current and noncurrent assets are shown net of collateral of $300 million and $92 million, respectively, and current and noncurrent liabilities are shown inclusive of collateral of $9 million and $24 million, respectively. The total cash collateral received, net of cash collateral posted and offset against mark-to-market assets and liabilities was $425 million at June 30, 2011.

[2] Current and noncurrent assets are shown net of collateral of $725 million and $199 million, respectively, and current and noncurrent liabilities are shown inclusive of collateral of $10 million and $17 million, respectively. The total cash collateral received net of cash collateral posted and offset against mark-to-market assets and liabilities was $951 million at December 31, 2010.