In a move that may have long-term implications for natural gas use in power generation, Portland General Electric (PGE) on Sunday officially began full participation in a real-time energy imbalance market (EIM) run by the California Independent System Operator (CAISO).

The move marks the culmination of two years of preparatory work and coordination between CAISO and the Portland, OR-based utility. CAISO said it would offer significant cost benefits for the expanding list of EIM participants that now cover eight western states.

PGE CEO Maria Pope said joining EIM should help the utility maintain reliability and keep power affordable while enhancing the grid.

PGE joins Arizona Public Service, Puget Sound Energy, NV Energy, and PacifiCorp in the market. By 2020 CAISO expects several other investor-owned and municipal utilities to join.

Mandated by the 2015 California Clean Energy and Pollution Reduction Act under Senate Bill 350, CAISO is applying the real-time market and increased reliance on renewable energy sources to reduce carbon emissions, including the amounts of natural gas, used for generation.

In 2016, the grid operator issued a12-volume, 688-page report analyzing various scenarios to create the regional electricity market to phase out the use of fossil fuels, including natural gas.

“The real-time energy market supports its participants by offering access to low-cost energy regardless of their location, a tool to help meet clean energy goals,” said CAISO CEO Steve Berberich. He predicted the expanding regional EIM would be a win-win for “everyone, including consumers.”