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                                                                 Exhibit 10.92bd

Summary of 2006 CEO Variable Incentive Plan and Officer Variable Incentive Plan

     On December 13, 2005, the Human  Resources  Committee (the  "Committee") of
the  Company's  Board of Directors  approved the 2006  Chairman and CEO Variable
Incentive Plan (the "CEO Incentive Plan").  The Company's  Chairman of the Board
and CEO,  William J. Post,  is eligible to receive an incentive  award under the
CEO Incentive  Plan.  Incentive  award  funding under the CEO Incentive  Plan is
triggered by the  attainment of specified 2006 Company  earnings.  The amount of
the award to Mr. Post is in the sole  discretion of the Committee.  Accordingly,
the Committee may consider  factors other than 2006 Company  earnings to measure
Mr. Post's performance.

     On December 14,  2005,  the  Company's  Board of  Directors,  acting on the
recommendation  of the Committee,  approved the 2006 Officer Variable  Incentive
Plan (the "Officer Incentive Plan"). Each of the Company's officers,  as well as
the officers of APS, are eligible to participate in the Officer  Incentive Plan,
including the following four most highly-compensated  current executive officers
(excluding the CEO) named in the Company's proxy  statement  relating to its May
18, 2005 annual meeting: Jack E. Davis, President and Chief Operating Officer of
the Company;  Donald E. Brandt,  Executive  Vice  President and Chief  Financial
Officer of the Company; James M. Levine, Executive Vice President, Generation of
APS; and Steven M.  Wheeler,  Executive  Vice  President,  Customer  Service and
Regulation of APS (the "Named Executive Officers").

     The Officer  Incentive Plan is composed of two components,  one of which is
based  on the  Company's  2006  earnings  and the  other on the  achievement  of
specified business unit results. Once a specified earnings threshold is met, the
achievement  of the  level of  earnings  and  business  unit  results  generally
determines what award, if any, the officer receives.  However, the amount of the
award,  if any, to each officer under the Officer  Incentive Plan is in the sole
discretion of the  Committee.  Accordingly,  the Committee may consider  factors
other than Company  earnings  and the  achievement  of business  unit results to
measure  performance,  including  input from the CEO about each  officer's  2006
achievements.

     Subject to the foregoing, award opportunities (expressed as a percentage of
the  officer's  base salary) for the  Chairman  and CEO and the Named  Executive
Officers will be based on the following performance measures (weighted according
to the indicated percentages):

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<TABLE>
<CAPTION>

       Officer                      Performance Measure(s)                   Award Opportunity
-------------------------    -------------------------------------       --------------------------------
<S>                          <C>                                         <C>
William J. Post                Company Earnings                            Threshold (63%)
                                                                           Midpoint (125%)
                                                                           Maximum (200%)

Jack E. Davis                  Company Earnings                            Threshold (37.5%)
                                                                           Midpoint (75%)
                                                                           Maximum (150%)

James M. Levine              - Company Earnings (50%)                      - Company Earnings:
                             - Fossil Business Unit Results                Threshold (0%)
                             (Preventable Recordable Injuries; Coal        Midpoint (25%)
                             Production Cost; Gas and Coal Units'          Maximum (50%) - Business
                             Annual Equivalent Availability Factor;        Unit Results (up to 50%)
                             Coal Units' Capacity Factor; O&M and
                             Capital Costs; and Environmental) (25%)
                             - Palo Verde Business Unit Results
                             (Nuclear Safety; Preventable Recordable
                             Injuries; Human Performance Events; Plant
                             Improvement Plan Performances; Nuclear
                             Capacity Factor; Equipment Reliability;
                             and O&M and Capital Costs) (25%)

Steven M. Wheeler            - Company Earnings (50%)                      - Company Earnings:
                             - Delivery Unit Results                       Threshold (0%)
                             (Preventable Recordable Injuries;             Midpoint (25%)
                             Customer Outcome Satisfaction; Business       Maximum (50%) - Delivery
                             Performance Trends; Customer Reliability;     Business Unit Results (up to
                             and Environmental Incidents) (50%)            50%)

Donald E. Brandt             - Company Earnings (50%)                      - Company Earnings:
                             - Shared Services Business Unit               Threshold (0%)
                             Results (Combined Fossil Business Unit,       Midpoint (25%)
                             Palo Verde Business Unit, and Delivery        Maximum (50%) - Shared
                             Business Unit Performance; Meeting or         Services Business Unit
                             Exceeding Budget Targets; and Preventable     Results (up to  50%)
                             Recordable Injuries) (50%)
</TABLE>

     Award  opportunities  for other  executive vice  presidents and senior vice
presidents  are up to 100% of base  salary (up to 50% based on Company  earnings
and  up to 50%  based  on the  achievement  of  business  unit  results).  Award
opportunities  for other  officers are up to 70% of base salary (up to 35% based
on Company  earnings  and up to 35% based on the  achievement  of business  unit
results).