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A senior staff member is currently leading program design, new program development and implementation support for new strategic electric vehicle (EV) pilots and other electrification projects for Arizona Public Service Company (APS or the Company).  These projects are part of an ongoing transformation of APS’ customer facing programs, including the Company’s legacy DSM programs, to focus on reducing summer peak demand, shifting energy use away from peak times to off-peak times, and exploring new opportunities to strategically build load in the middle of the day through load shifting, vehicle electrification, and reverse demand response.  The following figure shows APS forecast load shapes through 2032 and the influence of widespread market adoption of customer-sited solar electric systems. 

As shown in the following figure, this level of market adoption of solar can have an adverse impact on the APS system leading to negative low or negatively priced energy during mid-day with more expensive prices ramping to late afternoon/evening.  APS’ strategic electrification pilot projects are designed to give APS insight into how to promote electrification of the build and transportation sectors in a way that supports

APS resource needs by “filling the belly of the duck” and moderating afternoon/evening ramp-up as the solar resource diminishes.The Company’s new strategic electrification projects include: 

  • A non-residential managed electric vehicle (EV) charging pilot –The Managed Electric Vehicle Charging Pilot Program was designed to bring the benefits of EVs to participating customers in the most efficient manner for the electric system in order to maximize benefits for all APS customers. The program consists of APS owned, operated, and managed EV charging infrastructure designed for three different nonresidential applications: I) charging of commercial fleet vehicles, 2) workplace charging stations to charge employee vehicles, 3) and charging stations installed at multi-family properties. These stations serve residential multi-family dwellers and are being implemented in partnership with multi-family property management companies. APS will exercise dynamic scheduling of fleet EV charging to preclude charging during peak periods and ensure charging occurs during the most optimal times, as well as initiate demand response events at workplace and multi-family charging stations when needed. Charging times will be scheduled and managed to best avoid customer, distribution and system level peaks. 
  • An EV school bus pilot —This proposed pilot will provide assistance to targeted schools in the APS territory who have difficulty affording the cost of new infrastructure. The pilot program would provide a limited number of EV buses and charging infrastructure free of charge to participating school districts. Participating schools will be selected from a lottery of qualifying districts. The pilot will benefit participating schools through reduced infrastructure costs and significant fuel savings from replacing gasoline powered buses. In addition, participating schools will benefit from receiving new, safe reliable student transportation infrastructure. The program promotes sustainability through decreased reliance on diesel fueled transportation and reduced air emissions. Where possible, APS will work with participating schools to manage the charging of EV buses to take advantage of excess solar generation to further promote the sustainability of student transportation. APS will implement the pilot in coordination with the Company’s Solutions for Business Schools program and will work with key school stakeholders to define the list of qualifying schools for the pilot.
  • EV Ready New Homes – APS has proposed a new pilot measure within its residential new construction ENERGY STAR homes program, which will offer a $100 incentive to participating homebuilders who provide dedicated infrastructure to pre-wire their garages to accommodate future installation of level 2 charging stations.  By incorporating EV Ready into the home’s design and construction process, it helps encourage EV adoption and saves significant costs for homeowners who decide to add EV charging in the future.
  • Other Electrification Pilots – Tierra staff is supporting the design and development of additional non-vehicle electrification pilots for APS including an all-electric homes research study and new incentive programs for truck stop refrigeration, propane forklift conversions, and other emerging electrification opportunities.


Tom Hines