CAISO: PGE joins western EIM

The California ISO (CAISO) on Oct. 2 said that Portland General Electric (NYSE:POR) (PGE) on Oct. 1 became the fifth western utility to successfully begin full participation in the western Energy Imbalance Market (EIM).

CAISO said that it and PGE recently completed several weeks of extensive systems testing – the culmination of two years of preparatory work and coordination – and have certified that PGE is ready for financially binding participation in the EIM.  

The EIM uses state-of-the-art software to analyze regional grid needs and make available low-cost generation to meet demand every five minutes, CAISO said. Participating utilities save money by drawing automatically on the least-cost generating option available to meet short-term variations in their customers’ power use, CAISO said. That also allows participants to maximize the use of renewable resources, by making it easier to take immediate advantage of available wind and solar generation anywhere in the system while efficiently integrating their variable output with other dispatchable resources, CAISO said.

CAISO also noted that it estimates significant cost benefits have been produced for members since the EIM launched in November 2014, by effectively using the low-cost energy available in the region to meet changes in real-time energy demand. That is in addition to carbon reductions achieved through efficient dispatch of renewable resources, CAISO said, adding that those savings are projected to increase as more utilities join the market.

According to the “Western EIM Benefits Report,” for 2Q17, the benefits associated with participation in the EIM include cost savings and the use of surplus renewable energy to displace conventional generating resources. The estimated gross benefits for April, May and June are $39.52m, bringing the total benefits of EIM to $213.24m since the CAISO expanded its real-time market to balancing authority areas outside the CAISO in November 2014, the report said.

The report said that EIM is helping to displace less-clean energy supplies with surplus renewable energy that otherwise may have been curtailed. In 2Q17, the EIM used 67,055 MWh of surplus renewable energy to displace 28,700 metric tons of CO2 emissions, the report noted.

PGE joins Arizona Public Service, Puget Sound Energy, NV Energy, PacifiCorp, and CAISO, together serving more than 38 million consumers in California, Arizona, Oregon, Washington, Utah, Idaho, Wyoming, and Nevada, CAISO said in its Oct. 2 statement.

Future EIM participants include Idaho Power and Canada’s Powerex, which will enter the market in April 2018, followed by Seattle City Light, Los Angeles Department of Water & Power, and the Balancing Authority of Northern California/Sacramento Municipal Utility District in 2019, as well as Salt River Project in 2020, CAISO said.

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Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 15 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at