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): SEPTEMBER 29, 1999


                        PINNACLE WEST CAPITAL CORPORATION
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)



          Arizona                   1-8962                      86-0512431
- ----------------------------      ------------            ----------------------
(State or other jurisdiction      (Commission                 (IRS Employer
      of incorporation)           File Number)            Identification Number)


400 East Van Buren, P.O. Box 52132, Phoenix, Arizona            85072-2132
- ----------------------------------------------------            ----------
      (Address of principal executive offices)                  (Zip Code)



                                 (602) 379-2500
              (Registrant's telephone number, including area code)



                                      NONE
          (Former name or former address, if changed since last report)

ITEM 5. OTHER EVENTS

     As previously  reported,  Pinnacle West Capital Corporation (the "Company")
believes that there will be opportunities to expand its investment in generating
assets in the next five years.  See "Liquidity and Capital  Resources" in Item 2
of the Company's Quarterly Report on Form 10-Q for the fiscal quarter ended June
30, 1999. The Company has announced that it is currently planning to construct a
natural,  gas-fired  electric  generating  station  of  up  to  2,120  megawatts
approximately 50 miles west of Phoenix,  near the Palo Verde Nuclear  Generating
Station.  The plant will be  operated by Pinnacle  West  Energy  Corporation,  a
subsidiary  of the Company.  The Company  expects that the plant will consist of
four  530-megawatt  units,  which will come on line in phases beginning in 2003,
with the final unit anticipated to be operational  around 2007.  Construction on
the first unit is expected to begin in late 2000.

     The plant is expected to cost  approximately $1 billion,  assuming all four
units  are  built.  Projected  capital  expenditures  for  this  plant  and  the
previously-announced  potential  expansion at the West Phoenix  Power Plant are:
1999, $44 million; 2000, $125 million; and 2001, $238 million.

     The above discussion contains forward-looking statements that involve risks
and  uncertainties,   which  include,  but  are  not  limited  to,  the  ongoing
restructuring  of  the  electric   industry;   the  outcome  of  the  regulatory
proceedings  relating  to  the  restructuring;   regional  economic  and  market
conditions,  which could affect  customer growth and the cost of power supplies;
the cost of debt and  equity  capital;  weather  variations  affecting  customer
usage; the successful completion of large-scale  construction  projects; and the
strength  of the  real  estate  market.  These  factors  and the  other  matters
discussed  above may cause future results to differ  materially  from historical
results,  or from  results  or  outcomes  currently  expected  or  sought by the
Company.

                                   SIGNATURES


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


                                        PINNACLE WEST CAPITAL CORPORATION
                                                   (Registrant)



Dated: October 1, 1999                  By: /s/ Nancy C. Loftin
                                            ------------------------------------
                                            Nancy C. Loftin
                                            Vice President and General Counsel