Portland General Electric Co. became the fifth western utility to begin full participation in the western Energy Imbalance Market (EIM).

The Oregon utility and the California Independent System Operator (ISO) completed several weeks of 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 real-time energy market.

Map shows current and future EIM participants.The ISO estimates cost benefits have been produced for members since the EIM launched in November 2014, by using the low-cost energy available in the region to meet changes in real-time energy demand. Those savings are projected to increase as more utilities join the market.

The EIM uses software to analyze regional grid needs and make available low-cost generation to meet demand every five minutes. Participating utilities save money by drawing on the least-cost generating option available to meet short-term variations in their customers’ power use.

This also is intended to make it easier for participants to maximize the use of renewable resources, by taking advantage of available wind and solar generation anywhere in the system while integrating their variable output with other, dispatchable resources.

PGE joins Arizona Public Service, Puget Sound Energy, NV Energy, PacifiCorp and the ISO, together serving over 38 million consumers in California, Arizona, Oregon, Washington, Utah, Idaho, Wyoming and Nevada.

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 and Salt River Project in 2020.