September 6, 2022

Arizona entities announce commitment to SPP Markets+ development

LITTLE ROCK, ARK. — Southwest Power Pool (SPP) is pleased to announce several entities in Arizona have committed to supporting the next phase of Markets+ development. Arizona Electric Power Cooperative, Arizona Public Service Company, Salt River Project and Tucson Electric Power join seven other entities who previously committed to supporting market development (see SPP’s August 16 and August 29 announcements).

In a letter Aug. 31, the four Arizona entities declared their intent to work with SPP to build a market that includes “both a workable governance framework and a robust market design. This will be an important milestone that will enable us to collectively move forward to the next phase.”

These entities combined serve over 20,000 MW of peak demand in the desert southwest.  With this announcement, SPP has now received interest in supporting the next phase of Markets+ development from entities that serve over 50,000 MW of combined peak demand.

 Since December 2021, SPP has been working with western stakeholders to learn what they’d like out of a proposed day-ahead and real-time market. Based on its potential customers’ input, SPP will develop the Markets+ draft service offering, which will explain how Markets+ will address things like governance structure, market design and transmission availability.

 “We are pleased by the Arizona entities’ announcement to commit to phase one of Markets+ development,” said SPP President and CEO Barbara Sugg. “Adding the desert southwest region to the development of this market adds more value for all participants and we very much appreciate the contributions from these entities thus far.”

Last month, eight entities in the Pacific Northwest announced their intent to commit to phase one of Markets+ development: Bonneville Power Administration, Avista Corp., Chelan County Public Utility District, Grant County Public Utility District, Powerex Corp., Puget Sound Energy and Tacoma Power.

Markets+ is a conceptual bundle of services proposed by SPP that would centralize day-ahead and real-time unit commitment and dispatch, provide hurdle-free transmission service across its footprint and pave the way for the reliable integration of a rapidly growing fleet of renewable generation. For utilities that see value in these services but who aren’t ready to pursue full membership in a regional transmission organization (RTO) at this time, Markets+ provides a voluntary, incremental opportunity to realize significant benefits.

SPP staff met with western stakeholders Aug. 9-10 in Portland, Oregon to review work done on the service offering and discuss outstanding items and next steps. The draft service offering will be distributed Sept. 30, followed by a public comment period, with the final service offering distributed Nov. 18.

About SPP:  Southwest Power Pool, Inc. is a regional transmission organization: a not-for-profit corporation mandated by the Federal Energy Regulatory Commission to ensure reliable supplies of power, adequate transmission infrastructure and competitive wholesale electricity prices on behalf of its members. SPP manages the electric grid across 17 central and western U.S. states and provides energy services on a contract basis to customers in both the Eastern and Western Interconnections. The company’s headquarters are in Little Rock, Arkansas. Learn more at

Meghan Sever, 501-482-2393,