Washington, Arizona utilities begin testing CAISO EIM integration

Dive Brief:

Arizona Public Service, Puget Sound Energy and the California ISO are preparing for the utilities' full integration into the Western Energy Imbalance Market (EIM) in less than two months, operating under real-time market conditions though the transactions are not yet financially binding, RTO Insider reports.
That will happen Oct. 1; until then, officials say the parallel operations will give system engineers, grid operators and market managers a "test period" that will help ensure systems are performing as expected.
A recent California ISO report said the EIM has netted $88.2 million in benefits for its participants since November 2014.

Dive Insight:

California is integrating two out-of-state utilities into its EIM, but will remain in test phase for now.

“The EIM has been successful in saving tens of millions of dollars by leveraging the generation and transmission capacity across the West, with a larger geographic region to optimize,” CAISO President and CEO Steve Berberich said in a statement. “The addition of APS and PSE will create more opportunities to produce additional benefits, including improved integration of renewable energy.”

APS is based in Phoenix, while PSE operates in Washington state. The two will join PacifiCorp and NV Energy in the West's real-time energy market, serving customers in eight states. According to the ISO, Portland General Electric is scheduled to enter the market in October 2017, and Idaho Power will begin participation in the spring of 2018.

California launched the EIM in late 2014, and since then says it has produced more than $88 million in benefits to its customers. The market has also has saved 125,739 metric tons of carbon emissions since its launch by using 302,836 MWh of excess renewable energy to offset fossil fuel generation.

"These benefits are expected to grow as other utilities join the EIM," CAISO said.

Correction: An earlier version of this post was headlined Oregon, Arizona utilities begin testing CAISO EIM integration. That was incorrect. Puget Sound Energy serves electric customers in Washington.