8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of report (Date of earliest event reported):June 1, 2011

Commission File Number	Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number	IRS Employer Identification Number
1-8962	Pinnacle West Capital Corporation (an Arizona corporation) 400 North Fifth Street, P.O. Box 53999 Phoenix, AZ 85072-3999 (602) 250-1000	86-0512431
1-4473	Arizona Public Service Company (an Arizona corporation) 400 North Fifth Street, P.O. Box 53999 Phoenix, AZ 85072-3999 (602) 250-1000	86-0011170

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

oWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

oSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

oPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

oPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

This combined Form 8-K is separately filed or furnished by Pinnacle West Capital Corporation and Arizona Public Service Company.  Each registrant is filing or furnishing on its own behalf all of the information contained in this Form 8-K that relates to such registrant and, where required, its subsidiaries.  Except as stated in the preceding sentence, neither registrant is filing or furnishing any information that does not relate to such registrant, and therefore makes no representation as to any such information.

Item 7.01Regulation FD Disclosure.

Investor and Analyst Meetings and Rate Case Materials

Pinnacle West Capital Corporation (“Pinnacle West”) will be participating in various investor and analyst meetings from June 1, 2011 through June 3, 2011 and will be utilizing slides during those meetings.  Copies of the slides are attached hereto as Exhibit 99.1.

As described under Item 8.01 below, Arizona Public Service Company (“APS” or the “Company”) will be filing an application and related schedules with the Arizona Corporation Commission (the “ACC”) on June 1, 2011.  These materials are posted on an APS website at www.azenergyfuture.com.  The information on this website is not incorporated by reference into this report.

Item 8.01Other Events.

Retail Rate Case Filing with the Arizona Corporation Commission

On June 1, 2011, APS will file an application with the ACC for a net retail base rate increase of $95.5 million.  The Company will request that the increase become effective July 1, 2012.  The request would increase the average retail customer bill approximately 6.6%.  The filing is based on a test year ended December 31, 2010, adjusted as described below.  APS expects the ACC to issue a procedural schedule during the next sixty days detailing the timeline for addressing the request.

The key financial provisions of the request will include:

·an increase in non-fuel base rates of $194.1 million, before the reclassification into base rates of $44.9 million of revenues related to solar generation projects collected through the Company’s renewable energy surcharge (which will increase base rates) and $143.5 million of lower fuel and purchased power costs currently addressed through the Power Supply Adjustor (the “PSA”) (which will decrease base rates);

·a rate base of $5.7 billion, which approximates the ACC-jurisdictional portion of the book value of utility assets, net of accumulated depreciation and other credits, as of December 31, 2010, subject to certain adjustments, including plant additions under construction at the end of the test year that are currently in service or expected to be placed into service before the proposed rates are requested to become effective;

·the following proposed capital structure and costs of capital:

	Capital Structure		Cost of Capital
Long-term debt	46.1	%	6.38	%
Common stock equity	53.9	%	11.00	%
Weighted-average cost of capital			8.87	%

·a base rate for fuel and purchased power costs (“Base Fuel Rate”) of $0.03242 per kilowatt-hour (“kWh”) based on estimated 2012 prices (a decrease from the current Base Fuel Rate of $0.03757 per kWh).

The Company will propose that its PSA be modified to allow full pass-through of all fuel and purchased power costs, instead of the current 90/10 sharing provision.  In addition, APS will propose two new recovery mechanisms that would adjust electricity rates annually between changes in retail base rates.  The Efficiency and Infrastructure Account, a decoupling mechanism, would address recovery of the Company’s fixed costs after reflecting implementation of ACC-mandated energy efficiency standards and renewable distributed generation.  The Environmental and Reliability Account, a generation infrastructure adjustment mechanism, would allow recovery of the costs associated with generation investments related to new generation additions, generation efficiency projects and environmental compliance requirements.

On June 1, 2011, APS issued a press release announcing its filing with the ACC described above.  A copy of the press release is attached hereto as Exhibit 99.2.

Item 9.01Financial Statements and Exhibits.

(d)Exhibits

Exhibit No.	Registrant(s)	Description
99.1	Pinnacle West APS	Pinnacle West slides for use at various investor and analyst meetings from June 1, 2011 through June 3, 2011.
99.2	Pinnacle West APS	Press release issued June 1, 2011.

2

SIGNATURES

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

		PINNACLE WEST CAPITAL CORPORATION
		(Registrant)
Dated:	June 1, 2011	By:	/s/ James R. Hatfield
			James R. Hatfield
			Senior Vice President and Chief Financial
			Officer
		ARIZONA PUBLIC SERVICE COMPANY
		(Registrant)
Dated:	June 1, 2011	By:	/s/ James R. Hatfield
			James R. Hatfield
			Senior Vice President and Chief Financial
			Officer

3

EX-99.1

Exhibit 99.1

DELIVERING SUPERIOR SHAREHOLDER VALUE Investor and Analyst Meetings June 1 - 3, 2011

FORWARD-LOOKING STATEMENTS This presentation contains forward-looking statements based on current expectations, including statements regarding our 2011 earnings outlook. These forward-looking statements are often identified by words such as “estimate,” “predict,” “may,” “believe,” “plan,” “expect,” “require,” “intend,” “assume” and similar words. Because actual results may differ materially from expectations, we caution you not to place undue reliance on these statements. A number of factors could cause future results to differ materially from historical results, or from outcomes currently expected or sought by Pinnacle West or APS. These factors include, but are not limited to: our ability to achieve timely and adequate rate recovery of our costs, including returns on debt and equity capital; our ability to manage capital expenditures and other costs while maintaining reliability and customer service levels; variations in demand for electricity, including those due to weather, the general economy, customer and sales growth (or decline), and the effects of energy conservation measures and distributed generation; power plant performance and outages; volatile fuel and purchased power costs; fuel and water supply availability; regulatory and judicial decisions, developments and proceedings; new legislation or regulation including those relating to greenhouse gas emissions, renewable energy mandates, nuclear plant operation and energy efficiency standards; our ability to meet renewable energy requirements and recover related costs; risks inherent in the operation of nuclear facilities, including spent fuel disposal uncertainty; competition in retail and wholesale power markets; the duration and severity of the economic decline in Arizona and current real estate market conditions; the cost of debt and equity capital and the ability to access capital markets when required; changes to our credit ratings; the investment performance of the assets of our nuclear decommissioning trust, pension, and other postretirement benefit plans and the resulting impact on future funding requirements; the liquidity of wholesale power markets and the use of derivative contracts in our business; potential shortfalls in insurance coverage; new accounting requirements or new interpretations of existing requirements; generation, transmission and distribution facility and system conditions and operating costs; the ability to meet the anticipated future need for additional baseload generation and associated transmission facilities in our region; the willingness or ability of our counterparties, power plant participants and power plant land owners to meet contractual or other obligations or extend the rights for continued power plant operations; technological developments affecting the electric industry; and restrictions on dividends or other burdensome provisions in our credit agreements and Arizona Corporation Commission orders. These and other factors are discussed in Risk Factors described in Item 1A of the Pinnacle West/APS Annual Report on Form 10-K for the fiscal year ended December 31, 2010, which you should review carefully before placing any reliance on our financial statements, disclosures or earnings outlook. Neither Pinnacle West nor APS assumes any obligation to update these statements, even if our internal estimates change, except as required by law. 2

PINNACLE WEST: OUR VALUE PROPOSITION 3 Our commitment to investors: Deliver superior shareholder returns through …

4 PINNACLE WEST: OUR VALUE PROPOSITION

POSITIVE LONG-TERM DEMOGRAPHICS 5 CAPITALIZING ON INTRINSIC GROWTH Superior Growth APS’ customer growth generally outpaces U.S. and Arizona population growth. Annual Growth 1990 1995 2000 2005 2010 2015 Projected APS Customer Growth Arizona Population Growth US Population Growth 73% Millions APS Customer Growth

6 We reduced capital expenditures based on current economic conditions, yet still expect strong rate base growth. APS CAP EX DRIVES STRONG RATE BASE GROWTH APS Capital Expenditures APS Rate Base $ Millions $ Billions Projected Projected CAPITALIZING ON INTRINSIC GROWTH Other Distribution Transmission Renewable Generation Traditional Generation

7 PINNACLE WEST: OUR VALUE PROPOSITION

CUSTOMER SATISFACTION… A KEY PRIORITY 8 Our employees provide top-tier customer service. MAINTAINING OPERATIONAL EXCELLENCE Lowering Outage Time Per Customer Average Outage Minutes/Year Outstanding Residential Customer Satisfaction Rating Rating 2010 J.D. Power Residential Customer Survey APS Industry Average

Coal Performance Metrics Nuclear Capacity Factors SUPERIOR POWER PLANT PERFORMANCE 9 Our nuclear and coal plants are strong baseload resources. MAINTAINING OPERATIONAL EXCELLENCE APS Commercial Availability APS Capacity Factor Industry Capacity Factor Industry 90% APS 91% 65% 81% 92%

ENVIRONMENTAL, SUSTAINABILITY AND GOVERNANCE LEADERSHIP 10 Highest Rating (AAA) and Ranked #2 Electric Utility Dow Jones Sustainability Index Global 100 Most Sustainable Corporations in World Social Responsibility Index “Best in Class” Distinction Social Responsibility Reporting Highest Overall Score of U.S. Utilities U.S. DOE/EPA Sustained Excellence Award Top 10 Utility Solar Ranking MAINTAINING OPERATIONAL EXCELLENCE We are recognized worldwide for our achievements. Ranked 294 of 1,000 Companies Worldwide Ranked 15th Overall Highest for Any Utility

11 PINNACLE WEST: OUR VALUE PROPOSITION

12 MAKING COMPELLING CAPITAL INVESTMENTS RESOURCE PLANNING FOR RELIABILITY AND SUSTAINABILITY Additional Resources by 2025 • 2012 Four Corners transactions • Renewables (primarily solar and wind) • Energy efficiency • Natural gas Through a balanced resource mix including renewable resources and energy efficiency programs, we will meet future load growth. MW Projected 14,000 12,000 10,000 8,000 6,000 4,000 2,000 0 3% Four Corners Transactions, Net 4% Other Future Purchases 22% Future Renewable Resources 22% Future Energy Efficiency 50% Future Natural Gas Generation

RENEWABLE ENERGY RISES WITH THE SUN 13 We are helping Arizona become the “Solar Capital of the World.” Germany and Japan are among countries with highest installed solar capacity, yet have solar conditions far inferior to Arizona MAKING COMPELLING CAPITAL INVESTMENTS Arizona

14 • 100 MW photovoltaic solar plants to be owned by APS • Up to $500 million capital investment ($384 million committed to date) • In service 2011-2014 • Constructive rate recovery APS has contracted to date for 83% of the program. Announced Projects to Date Capacity Paloma 17 MW Cotton Center 17 MW Hyder 16 MW Chino Valley 19 MW Luke Air Force Base 14 MW AZ SUN PROGRAM PROVIDES EARNINGS GROWTH POTENTIAL MAKING COMPELLING CAPITAL INVESTMENTS

15 MAKING COMPELLING CAPITAL INVESTMENTS FOUR CORNERS POWER PLANT TRANSACTIONS Our proposal represents a balanced solution to new environmental regulations. Acquire Southern California Edison’s 739 MW interest in Units 4 & 5 and shut down 560 MW Units 1 – 3 Purchase price: $294 million Acquisition target date: late 2012 Estimated environmental compliance investment: $300 million Finance with mix of debt and equity Arizona, California and other regulatory approvals required Economic, environmental and social benefits ACC Procedural Schedule May 31, 2011 Staff/Intervenor direct testimony June 22, 2011 APS rebuttal testimony July 14, 2011 Hearing to commence

TRANSMISSION INVESTMENT ESSENTIAL 16 • 10-Year Transmission Plan (115-kV and above) • $450 million of new transmission investment • 258 miles of new lines • Increases import capability by 6% to metro Phoenix and 39% to Yuma • Projects to deliver renewable energy approved by ACC • Transmission investment diversifies regulatory risk • Constructive regulatory treatment • FERC formula rates and retail adjustor Strategic transmission is necessary to maintain reliability and deliver diversified resources to our customers. Legend NORTH SAGUARO N . GILA PALO VERDE - HASSAYAMPA YUCCA GILA BEND REDHAWK KYRENE WEST WING BAGDAD 2016 PINNACLE PEAK CHOLLA NAVAJO 2014 CORONADO FLAGSTAFF ( APS ) 2013 2010 SUNDANCE 2014 FOUR CORNERS DESERT BASIN Line Relocation 2014 Planned lines Existing lines Solar potential area Wind potential area 2012 DELANY 2012 MAZATZAL 2013 MORGAN 2010 2014 MAKING COMPELLING CAPITAL INVESTMENTS

17 PINNACLE WEST: OUR VALUE PROPOSITION

ARIZONA CORPORATION COMMISSIONERS 18 IMPROVING OUR REGULATORY ENVIRONMENT Sandra Kennedy (Dem) Paul Newman (Dem) Bob Stump (Rep) Brenda Burns (Rep) Gary Pierce (Rep)* Chairman Terms Through January 2013 The new composition provides opportunities for additional relationships and process efficiencies. Terms Through January 2015 * Term limited

2011 RETAIL RATE CASE FILING BENEFITS 19 Provides financial support APS needs to achieve Arizona’s energy goals Encourages progress toward sustainable energy future Supports renewable energy and energy efficiency Continues constructive regulatory framework established in 2009 regulatory settlement Promotes rate gradualism for customers IMPROVING OUR REGULATORY ENVIRONMENT The rate case provisions contain a number of benefits for customers and shareholders.

2011 RETAIL RATE CASE FILING KEY FINANCIAL COMPONENTS 20 APS has requested a base rate increase to become effective July 1, 2012. IMPROVING OUR REGULATORY ENVIRONMENT Annual Revenue Change Non-fuel base rate increase $ 194.1 6.6% Amounts transferring from adjustment mechanism revenues Renewable Energy Surcharge revenues related to AZ Sun and other solar projects 44.9 Power Supply Adjustor revenues (refunds) (143.5) Net base rate increase $ 95.5 3.3%

2011 RETAIL RATE CASE FILING KEY FINANCIAL ASSUMPTIONS 21 IMPROVING OUR REGULATORY ENVIRONMENT Rate base $5.7 billion Return on equity 11% Capital structure Long-term debt 46.1% Common equity 53.9% Base fuel rate (¢/kWh) 3.25 Projected fuel-price year for base fuel rate 2012 Test year ended December 31, 2010 Updated rate base, cost of capital and fuel prices underpin the rate request amounts.

2011 RETAIL RATE CASE FILING DETAILS OF REQUEST 22 Post test-year plant additions through rate effective date $259 million AZ Sun projects $161 million other projects Revenue-per-customer decoupling mechanism Infrastructure tracker New generation additions and generation efficiency projects Environmental compliance investments 100% Power Supply Adjustor Remaining portions of AZ Sun project to be recovered through RES until included in base rates (consistent with treatment for first 50 MW) IMPROVING OUR REGULATORY ENVIRONMENT Other key provisions continue constructive regulatory treatment and limit regulatory lag.

APS LINE EXTENSION POLICY PROPOSAL 23 IMPROVING OUR REGULATORY ENVIRONMENT APS has requested line extension policy changes in a separate docket. Restore sharing of extension costs between new customers and APS Implement 750-foot free footage allowance and other measures dependent upon customer class Accounting to revert to contributions in aid of construction or customer advances Policy change to be implemented concurrently with new base rates at conclusion of general retail rate case Application filed May 20, 2011

DECOUPLING MODEL 24 APS requested decoupling model consistent with policy statement for consideration in general rate case filing Fixed-cost revenue per customer methodology Decoupling provides method to mitigate disincentives associated with energy efficiency and distributed generation by separating revenues from sales volumes Arizona Corporation Commission unanimously approved supportive decoupling policy statement, December 2010 Decoupling mechanism to be addressed by the commission on a utility-by-utility basis State regulators have approved a policy statement supporting a revenue-per-customer approach. IMPROVING OUR REGULATORY ENVIRONMENT

25 PINNACLE WEST: OUR VALUE PROPOSITION

26 Our on-going earnings have improved. STRENGTHENING OUR FINANCIAL PROFILE CONSOLIDATED ON-GOING EPS OUTLOOK Per Share $3.00 - $3.15 See key factors and assumptions in Appendix. As of 4/29/11

27 Improving our earned return on equity is one of our top priorities. Earned ROEs Key Initiatives • Supportive electric utility rates • Regulatory framework improvements • Cost management initiatives • Efficiency and effectiveness throughout organization STRENGTHENING OUR FINANCIAL PROFILE ROE IMPROVEMENT: A MULTI-PRONGED APPROACH * On-going earnings APS PNW*

28 Our goal is to keep O&M growth in line with retail sales growth. $ Millions Excludes RES and demand-side management costs STRENGTHENING OUR FINANCIAL PROFILE APS OPERATIONS & MAINTENANCE EXPENSE TRENDS

AMPLE FINANCING ACCESS 29 Investment-grade credit ratings, capitalization and liquidity should provide adequate access to bank and capital markets. 2011 $500M APS revolver refinancing* 2011 $175M PNW senior notes refinancing* 2011 $400M APS senior notes refinancing 2012 $375M APS senior notes refinancing 2012 APS new debt issuance 2012 PNW equity issuance (at earliest) 2011 - 2012 Major Financing Activities STRENGTHENING OUR FINANCIAL PROFILE $ Billions Consolidated Capitalization APS ACC Capitalization Consolidated Liquidity December 31, 2010 50.7% 53.9% Capitalization and Liquidity *Completed.

TOP-TIER DIVIDEND YIELD 30 Pinnacle West’s annual dividend is $2.10 per share — providing a top-quartile yield with a near-average payout. STRENGTHENING OUR FINANCIAL PROFILE Dividend Yield Dividend Payout Industry Averages PNW Yield as of April 30, 2011 Payout 12 Months Ended December 31, 2010

31 SUPERIOR SHAREHOLDER RETURNS Our total return to shareholders has outperformed our industry and the broad market over the past five years. STRENGTHENING OUR FINANCIAL PROFILE (18.6%) Pinnacle West S&P 500 S&P 1500 Electric Utilities 50% 40% 30% 20% 10% 0% (10)% (20)% 19.5% 15.0% 4.4% 45.5% 45.4% 9.0% 17.4% (8.3)% 32.6% 12.0% 20.9% 1 Year 2 Years 3 Years 5 Years Periods ended December 31, 2010

32 PINNACLE WEST: OUR VALUE PROPOSITION Our commitment to investors Deliver Superior Shareholder Returns

33 APPENDIX

A RESPECTED, VETERAN LEADERSHIP TEAM 34 Our top executives have more than 130 combined years of creating shareholder value in the energy industry. Jim Hatfield SVP & CFO Mark Schiavoni SVP Fossil Generation Dave Falck EVP, General Counsel & Secretary Randy Edington EVP & Chief Nuclear Officer Don Brandt Chairman & CEO Don Robinson APS President & COO SUPERIOR SHAREHOLDER RETURNS

PINNACLE WEST: WHO WE ARE 35 We are a vertically integrated, regulated electric utility. Vertically Integrated Regulated Electric Utility $12 Billion Assets Non-Utility Subsidiaries $56 Million Assets NYSE Ticker PNW Market Cap $5 Billion Enterprise Value $8 Billion

FOCUSING ON CORE REGULATED ELECTRIC UTILITY BUSINESS 36 APS is Arizona’s largest and longest-serving electric utility. Service Territory • 1.1 million customer accounts • 34,646 square miles Customer Growth • 1.7% average annual growth expected 2011-2013 • 3-4% historical average — well above industry average Resources • 6,293 MW owned/leased capacity • 2,454 MW contracted conventional resources • 605 MW contracted renewables 2010 Peak Demand – 6,936 MW CONTINENTAL UNITED STATES STATE OF ARIZONA

37 • Electricity gross margin (operating revenues,* net of fuel and purchased power expense) about $2.05 billion to $2.10 billion; • Retail customer growth about 1 percent; • Weather-normalized retail electricity sales volume growth about 1 percent taking into account effects of the Company’s energy efficiency initiatives; • Normal weather for year; • Operating expenses (operations and maintenance,* depreciation and amortization; and taxes other than income taxes) about $1.32 billion to $1.35 billion; • Interest expense, net of allowances for borrowed and equity funds used during construction, about $200 million to $210 million; • Net income attributable to noncontrolling interests about $20 million to $25 million; • Effective tax rate about 34 percent; • Full-year effect of 2010 equity issuance; and • APS earnings to contribute substantially all of consolidated earnings. 2011 ON-GOING EPS GUIDANCE Key Factors and Assumptions as of April 29, 2011. STRENGTHENING OUR FINANCIAL PROFILE * Excludes approximately $149 million of O&M, and offsetting operating revenues, associated with renewable energy, demand-side management and similar regulatory programs, as well as $28 million pretax related to settlement of prior-period Four Corners transmission rights-of-way.

38 Our cost management and efficiency efforts will improve financial results beyond those achievable solely through regulatory decisions. STRENGTHENING OUR FINANCIAL PROFILE COST EFFICIENCY SUPPORTS FUTURE RESULTS Enterprise-wide emphasis Better leverage technology Optimize assets and resources Effective, efficient execution Engaged, motivated workforce Cost Efficiency

CREDIT RATINGS 39 APS Parent Senior Unsecured Moody’s Baa2 Baa3* S&P BBB- BB+* Fitch BBB - Outlook Moody’s Stable Stable S&P Positive Positive Fitch Stable Stable APS has investment-grade credit ratings. STRENGTHENING OUR FINANCIAL PROFILE *Preliminary We are disclosing these ratings to enhance understanding of our sources of liquidity and the effects of our ratings on our costs of funds.

S&P CREDIT METRICS 40 APS FFO / Debt FFO / Interest Debt / Capitalization Pinnacle West FFO / Debt FFO / Interest Debt / Capitalization Our key credit metrics have been improving. STRENGTHENING OUR FINANCIAL PROFILE 2006 2007 2008 2009 2010 17.5% 17.2% 22.1% 22.8% 22.3% 4.2x 4.1x 5.1x 4.8x 4.6x 56.6% 55.2% 57.4% 56.8% 53.0% 16.3% 15.7% 18.0% 18.4% 22.5% 3.8x 3.7x 4.3x 4.0x 4.6x 57.0% 57.0% 59.4% 59.8% 55.1%

2010 RETAIL CUSTOMER, SALES AND REVENUE MIXES 41 Residential Commercial Industrial Other Customers Year-End 1.1 Million Retail Sales 27,709 GWh Operating Revenues $2.9 Billion 8% 45% 47% 11% 89% Our business mix is attractive due to favorable climate and other conditions in our market area. MAINTAINING OPERATIONAL EXCELLENCE

42 2010 APS GENERATION AND ENERGY FUEL MIXES Energy Fuel Mix 33,781 GWh Generation Fuel Mix 26,828 GWh Generation Capacity Mix 6,293 MW Nuclear Coal Gas & Oil Purchased Power Our balanced resource mix provides our customers reliability and manages price volatility. MAINTAINING OPERATIONAL EXCELLENCE 46% 16% 21% 16% 36% 20% 34% 54% 28% 18%

Coal Performance Metrics Nuclear Capacity Factors SUPERIOR POWER PLANT PERFORMANCE 43 Our nuclear and coal plants are strong baseload resources. MAINTAINING OPERATIONAL EXCELLENCE APS Commercial Availability APS Capacity Factor Industry Capacity Factor Industry 90% APS 91% 65% 81% 92% • Returned to superior performance • 3,938 MW total managed capacity • 1,146 MW total APS share • 2014 goals: • Consistent site capacity factor greater than 90% • Operating costs excluding fuel less than $0.02/kWh • Top-quartile safety • 20-year license extension approved by U.S. Nuclear Regulatory Commission • Consistent solid performance • 2,747 MW total managed capacity • 1,753 MW APS share • Highly experienced management • Fleet operating strategy • New commercial availability metric measures plant reliability during high-demand periods and market responsiveness

A WELL-BALANCED GENERATION PORTFOLIO 44 Fuel / Plant Location Units Dispatch Commercial Ops. Date Operator Ownership Interest1 Net Capacity (MW) Nuclear Palo Verde Wintersburg, AZ 1-3 Base 1986 - 1989 APS 29.1% 1,146 Total Nuclear 1,146 Coal Cholla Joseph City, AZ 1-3 Base 1962 - 1980 APS 100 647 Four Corners Farmington, NM 1-3 Base 1963 - 1964 APS 100 560 Four Corners Farmington, NM 4,5 Base 1969 - 1970 APS 15 231 Navajo Page, AZ 1-3 Base 1974 - 1976 SRP 14 315 Total Coal 1,753 Gas/Oil - Combined Cycle Redhawk Arlington, AZ 1,2 Intermediate 2002 APS 100 984 West Phoenix Phoenix, AZ 1-5 Intermediate 1976 - 2003 APS 100 887 Total Gas/Oil - Combined Cycle 1,871 Gas/Oil - Steam Turbines Ocotillo Tempe, AZ 1,2 Peaking 1960 APS 100 220 Saguaro Red Rock, AZ 1,2 Peaking 1954 - 1955 APS 100 210 Total Gas/Oil - Steam Turbines 430 Gas/Oil - Combustion Turbines Sundance Casa Grande, AZ 10 Peaking 2002 APS 100 420 Yucca Yuma, AZ 6 Peaking 1971 - 2008 APS 100 243 Saguaro Red Rock, AZ 1-3 Peaking 1972 - 2002 APS 100 189 West Phoenix Phoenix, AZ 1,2 Peaking 1972 - 1973 APS 100 110 Ocotillo Tempe, AZ 1,2 Peaking 1972 - 1973 APS 100 110 Douglas Douglas, AZ 1 Peaking 1972 APS 100 16 Total Gas/Oil - Combustion Turbines 1,088 Solar Solar -- As Available APS 100 5 1996 - 2006 Total Solar Total Generation Capacity 6,293 As of December 31, 2010 1Includes leased generating plants. Multiple State-wide Facilities 5 MAKING COMPELLING CAPITAL INVESTMENTS

RENEWABLE PURCHASE POWER CONTRACTS 45 MAKING COMPELLING CAPITAL INVESTMENTS Fuel / Contract Location Original Developer Status 1 PPA Signed Commercial Operation Date Term (years) Capacity Net (MW) Solar Solana Gila Bend, AZ Abengoa UC Feb-2008 2013 30 250 Ajo Ajo, AZ Recurrent UC Jan-2010 2011 25 5 Prescott Prescott, AZ SunEdison UC Feb-2010 2011 30 10 Solar 1 Tonopah, AZ Not Disclosed AD Jan-2011 2012 30 15 Total Solar 280 Wind Aragonne Mesa Santa Rosa, NM Babcock & Brown IO Dec-2005 Dec-2006 20 90 High Lonesome Mountainair, NM Foresight / EME IO Feb-2008 Jul-2009 30 100 Perrin Ranch Wind Williams, AZ NextEra Energy AD Jul-2010 2011 25 99 Total Wind 289 Geothermal CE Turbo Imperial County, CA CalEnergy IO Jan-2006 Jan-2006 23 10 Total Geothermal 10 Biomass Snowflake Snowflake, AZ Snowflake White Mtn. Power IO Aug-2006 Jun-2008 15 10 Snowflake Snowflake, AZ IO Aug-2010 Jun-2008 1 10 Total Biomass 20 Biogas Glendale Landfill Glendale, AZ Glendale Energy LLC IO Jul-2008 Jan-2010 20 3 Landfill 1 Surprise, AZ Not Disclosed AD Dec-2010 2012 20 3 Total Biogas 6 Total Renewable Contracted Capacity 605 As of April 30, 2011 1 AD = Advanced Development; UC= Under Construction; IO = In Operation Snowflake White Mtn. Power

46 FOUR CORNERS POWER PLANT FACTS & FIGURES MAKING COMPELLING CAPITAL INVESTMENTS Common Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Commercial Operation Date 1963 1963 1964 1969 1970 Original Cost ($M) $37 $369 $166 Net Book Value at 12/31/10 ($M) $20 $125 $63 Current Depreciation Ends 2031 Mid-2016 Mid-2016 Mid-2016 2031 2031 Current Expiration Dates Site Lease July 6, 2016 BHP Coal Agreement July 6, 2016 Certain Related Rights-of-Way July 6, 2016 Total Employees (549) 48 Common (75% Native Americans) + 75 Matrix 193 233 Capacity (MW) 170 170 220 770 770 Ownership Percentages Arizona Public Service 100% 100% 100% 15% 15% Southern California Edison - - - 48% 48% Public Service Company of New Mexico - - - 13% 13% Salt River Project - - - 10% 10% El Paso Electric - - - 7% 7% Tucson Electric Power - - - 7% 7% Heat Rate (Btu/kWh) 10,816 11,051 10,614 9,443 10,035

47 Renewable Energy (RES) Minimum Requirements Portion of retail sales to be supplied by renewable resources 5% by 2015 15% by 2025 Distributed energy component 30% of total requirement by 2012 APS committed to approximately double 2015 requirement Pursuant to 2009 regulatory settlement Energy Efficiency Requirements Increasing annually 2011-2020 Cumulative energy savings as a percent of retail sales 3% by 2012 9.5% by 2015 22% by 2020 ARIZONA’S RENEWABLE RESOURCE AND ENERGY EFFICIENCY STANDARDS We are committed to aggressive renewable and energy efficiency standards. MAKING COMPELLING CAPITAL INVESTMENTS

AZ SUN PROGRAM SUMMARY 48 MAKING COMPELLING CAPITAL INVESTMENTS APS is investing up to $500 million to own 100 MW of solar generation by year-end 2014. Name Location Capacity Developer Target COD* Paloma Gila Bend, AZ 17 MW First Solar 2011 Cotton Center Gila Bend, AZ 17 MW Solon 2011 Hyder Phase 1 Hyder, AZ 11 MW SunEdison 2011 Hyder Phase 2 Hyder, AZ 5 MW SunEdison 2012 Chino Valley Chino Valley, AZ 19 MW SunEdison 2012 Luke Air Force Base Glendale, AZ 14 MW SunPower 2012/2013 Total Announced To Date 83 MW To Be Announced 17 MW Program Total 100 MW As of February 16, 2011 * Commercial Operation Date

SOLANA: A “SUNNY PLACE” 49 • 250-MW 30-year PPA for all output (~900 GWh/year) • Concentrating solar trough facility 70 miles southwest of Phoenix • Expected to be first major stored-heat plant in U.S. on targeted 2013 commercial operation date • Near existing transmission lines • Thermal storage capability with summer on-peak capacity factor +90% • To be built, owned and operated by Abengoa Solar • DOE loan guarantee financing finalized MAKING COMPELLING CAPITAL INVESTMENTS Solana will provide about one-third of APS’ renewable energy target of 10% by 2015.

50 APS ENERGY EFFICIENCY INITIATIVES INCREASING • Program costs currently recovered through retail DSM adjustor • Decoupling or other financial mechanism to be proposed in 2011 base rate case • Under retail regulatory settlement, APS to achieve additional retail sales savings of 3.75% in 2010-2012 • Arizona energy efficiency rules require cumulative savings of 22% of retail sales by 2020 Cumulative Annual Energy Savings Associated with EE/DSM Programs MAINTAINING OPERATIONAL EXCELLENCE APS plans to double customers’ energy efficiency savings from 2010 through 2012. GWh

IMPROVING REGULATORY FRAMEWORK 51 On-going APS meetings with stakeholders Progress on generic issues • Approvals by ACC in 2010 • Decoupling policy statement • Resource planning rules • Energy efficiency rules • Renewable transmission action plan • Other generic dockets underway • Rate case process streamlining • Line extensions 2011 general retail rate case filing Opportunities exist to continue regulatory dialogue, cooperatively addressing shareholder and stakeholder interests. IMPROVING OUR REGULATORY ENVIRONMENT

• Strengthens APS’ earned ROE and financial condition • Supports common dividend • Demonstrates increased cooperation among APS, ACC Staff, residential consumer advocate (RUCO) and other intervenors • Allows opportunity to help shape Arizona’s energy future outside continual rate cases • Provides earnings support until next base rate case • Estimated pretax earnings benefits: $165 million, 2010; $180 million, 2011; and $254 million, 2012 • Establishes expedited process for future base rate cases • Allows next rate case filing on or after June 1, 2011, for rate changes effective on or after July 1, 2012 52 PROGRESSIVE REGULATORY SETTLEMENT POSITIONS APS WELL THROUGH 2012 IMPROVING OUR REGULATORY ENVIRONMENT APS’ 2009 regulatory settlement contains a number of investor benefits.

2009 REGULATORY SETTLEMENT SUMMARY 53 IMPROVING OUR REGULATORY ENVIRONMENT The settlement provisions include earnings support until APS’ next rate case decision. Estimated Pretax Earnings Benefits $ Millions 2010 2011 2012 Settlement agreement terms Base rate increase $ 207 $ 207 $ 207 Line extensions treated as revenue 23 25 49 Pension and OPEB deferrals – 13 29 Palo Verde depreciation reduction _ _ 34 Subtotals 230 245 319 Less interim base rate surcharge that ended upon general rate case implementation (65) (65) (65) Total $ 165 $ 180 $ 254

OUR REGULATORY MIX 54 Most Recent Rate Decisions $6.8 Billion Total Approved Rate Base ACC FERC Rates Effective Date 1/1/2010 6/1/2011 Test Year Ended 12/31/2007* 12/31/2010 Rate Base $5.6 B $1.2 B Equity Layer 54% 54% Allowed ROE 11.00% 10.75% IMPROVING OUR REGULATORY ENVIRONMENT The bulk of APS’ revenues comes from a regulated retail rate base and a meaningful transmission business. * Adjusted to include post test-year plant in service through June 30, 2009 Transmission 18% Generation & Distribution 82%

55 APS REVENUES BY RECOVERY MECHANISM Supportive regulatory treatment through adjustment mechanisms supplements base rates. Test Year Historical Forecast Base Rates RES TCA PSA DSM Other $ Millions Regulated Electricity Revenue by Recovery Mechanism IMPROVING OUR REGULATORY ENVIRONMENT

56 • FERC Formula Rates adopted in 2008 • Adjusted annually with 10.75% allowed ROE • Based on FERC Form 1 and certain projections • Retail portion flows through ACC Transmission Cost Adjustor (TCA) • Recent transmission revenue changes CONSTRUCTIVE TRANSMISSION RATE REGULATION Annual Revenue Rate Effective Dates Annual Revenue Rate Effective Dates Annual Revenue Rate Effective Dates Retail Portion (TCA) $ 38 M 7/1/2011* $(10) M 8/1/2010 $ 21 M 8/1/2009 Wholesale Portion $ 6 M 6/1/2011 $ (2) M 6/1/2010 $ 2 M 6/1/2009 Total Increase (Decrease) $ 44 M $(12) M $ 23 M Equity Ratio 54% 51% 55% Rate Base $1.2 B $1.1 B $1.1 B Test Year 2010 2009 2008 IMPROVING OUR REGULATORY ENVIRONMENT We have achieved transmission rate treatment with annual adjustments. * Requested

57 SIGNIFICANT REGULATORY PROGRESS SINCE 2005 IMPROVING OUR REGULATORY ENVIRONMENT We have achieved a more supportive regulatory structure and improvements in cost recovery timing. Mechanism Adopted/ Last Adjusted Description Power Supply Adjustor (“PSA”) April 2005 / February 2011 Recovers 90% of variance between actual fuel and purchased power costs and base fuel rate Includes forward-looking, historical and transition components Renewable Energy Surcharge (“RES”) May 2008 / January 2011 Recovers costs related to renewable initiatives Collects projected dollars to meet RES targets Provides incentives to customers to install distributed renewable energy Demand-Side Management Adjustment Clause (“DSMAC”) April 2005 / March 2011 Recovers costs related to energy efficiency and DSM programs above $10 million in base rates Provides performance incentive to APS for net benefits achieved Provides rebates and other incentives to participating customers Environmental Improvement Surcharge (“EIS”) July 2007 / July 2007 Recovers retroactively costs related to environmental upgrades not fully recovered through base rates Allows for cost recovery of ACC-approved projects Retail Line Extension Fees February 2008 /January 2010 “Pay as you go” mechanism collects dollars spent for new distribution construction at beginning of project Better protects existing customers by allocating cost of expansion to developers Transmission Cost Adjustor (“TCA”) April 2005 / July 2011* Recovers FERC-approved transmission costs related to retail customers Resets annually as result of FERC Formula Rate process (see below) FERC Formula Rates 2008 / June 2011 Recovers transmission costs based on historical costs per FERC Form 1 and certain projected data Resets annually * Requested

EX-99.2

Exhibit 99.2

FOR IMMEDIATE RELEASE June 1, 2011

Media Contacts:	Alan Bunnell	(602) 250-3376	Page 1 of 2
	Jim McDonald	(602) 321-3738 (cell)
Analyst Contact:	Rebecca Hickman	(602) 250-5668
	Geoff Wendt	(602) 250-5643
Website:	aps.com/newsroom

APS FILING AIMS TO CONTINUE ADVANCES

IN SUSTAINABILITY AND RELIABILITY

PHOENIX — Arizona Public Service Company later today will ask the Arizona Corporation Commission for approval to increase customer bills by 6.6 percent, effective July 1, 2012. The request is needed to help meet Arizona’s energy goals, including:

·Continuing to maintain and upgrade the reliable electric system APS customers expect.

·Producing 15 percent of the electricity used by APS customers from renewable generation by 2020. Today, the company obtains 3 percent of its generation from renewables.

·Meeting 22 percent of the energy needs of the company’s customers through energy efficiency measures by 2020. The current number for APS customers is 3.6 percent.

“Two years ago, we came together with the ACC and 21 other stakeholders to create a long-term vision for Arizona’s energy future. That shared vision includes continued upgrades to our power grid, ambitious goals for a cleaner energy supply and new energy efficiency programs for our customers,” said Don Robinson, APS President and Chief Operating Officer. “We are meeting those goals and spending about $1 billion each year to create a cleaner, reliable and more efficient energy future for Arizona. Now we are asking the ACC to continue its support of this plan.”

The rate request also would enable the company to incorporate more smart technology into Arizona’s electric grid and enhance control for customers over their energy use and bills.

If the company’s request is approved, the typical APS residential customer using 1,100 kilowatt hours per month would see a bill increase of $8.36 for a total of $135.61.

Robinson said that most APS customers could offset the impact of the rate increase by participating in one or more of the company’s energy efficiency programs. “The savings can be substantial,” Robinson said. “For example, participation in our refrigerator recycling program could offset the entire increase. Even something as simple as installing compact fluorescent light bulbs can make a big difference.”

APS FILES RATE REQUEST WITH ACC	June 1, 2011
	Page 2 of 2

This request comes only after significant cost management on the part of the company. Since the 2009 rate case, APS has cut operating costs by more than $37 million. The Nuclear Regulatory Commission’s recent approval of Palo Verde’s application for a 20-year renewal of its operating license also lowered the request.

The filing also seeks to modernize the way electric rates are set to reflect the importance of energy efficiency as a clean and affordable way to meet customer demand. “The current rate structure was created in the early 1900s, long before energy conservation became an important national priority,” said Robinson. The APS proposal would eliminate the company’s incentive for customers to consume more energy and ensure that energy efficiency programs can be used when the best resource choice for APS and its customers is using less energy.

These ongoing efforts are paying off for customers:

·The APS system continues as one of the most reliable in the nation. The company is among the industry leaders in reliability measurements that track frequency and duration of service interruptions.

·Renewable generating resources have increased from almost nothing (less than one megawatt) 10 years ago to enough (304 megawatts) to power a city the size of Yuma today.

·APS is spending about $500 million to build 100 megawatts of new photovoltaic solar plants located across Arizona that together are known as “AZ Sun.”

·In 2010, APS energy efficiency programs resulted in 319 million kilowatt hours of savings, which is equal to the total usage of approximately 24,000 average residential customers.

·APS has installed nearly 610,000 smart meters and is testing and implementing other smart grid technologies.

·Customer satisfaction levels are at all-time highs. According to the latest J.D. Power residential survey that measures such factors as price, billing and payment, customer service and power quality and reliability, APS ranks third nationally among 55 investor-owned utilities.

“All of these are huge steps, but especially our commitment to take advantage of the energy potential of the sun,” said Robinson. “The sun is an abundant resource in Arizona and reduces our need to burn fossil fuels. The funding provided by this rate request will help build a reliable and sustainable energy future for Arizona.”

For more information on the APS request, go to azenergyfuture.com.

APS, Arizona’s largest and longest-serving electricity utility, serves more than 1.1 million customers in 11 of the state’s 15 counties. With headquarters in Phoenix, APS is the principal subsidiary of Pinnacle West Capital Corp. (NYSE: PNW).

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