Western Energy Imbalance Market (WEIM) has reported impressive cost-saving benefits of $462.05 million in the third quarter of 2023. This achievement brings the cumulative leveraged savings in California and the broader western United States to a substantial $4.66 billion since the market's inception in 2014.
The remarkable increase in economic benefits during the third quarter is attributed to the growing number of market participants and a more diverse set of resources spanning a wider geographical footprint. This expansion has allowed for cleaner and more affordable energy sources to meet demand, displacing more expensive generation methods.
The WEIM operates by facilitating the purchase and sale of power close to the time it is generated and consumed, a vital function in maintaining interconnection reliability, especially during the summer of 2023. Leveraging state-of-the-art technology, the market identifies and delivers the lowest-cost resources to address immediate power needs and effectively manages congestion on transmission lines to ensure grid reliability.
Moreover, the WEIM provides system operators with real-time visibility into neighboring grids, leading to more efficient supply-demand balancing. This capability is crucial, particularly during summer evenings when electricity consumption remains high, but solar generation declines.
In 2023, the WEIM welcomed three new entities, bringing the total number of participants to 22, representing 11 western states. Notable members with hydroelectric power in their portfolios include Avangrid, Avista, Idaho Power, Los Angeles Department of Water and Power, NorthWestern Energy, PacifiCorp, Portland General Electric, Puget Sound Energy, Seattle City Light, Salt River Project, Tacoma Power, Turlock Irrigation District, and the Bonneville Power Administration, which markets hydropower from the Federal Columbia River Power System.
Thanks to enhanced regional coordination within the WEIM, the market has effectively reduced greenhouse gas emissions by identifying excess clean power at risk of curtailment and facilitating its movement across the Western U.S. Since its establishment in 2014, the WEIM has contributed to a reduction of more than 904,219 metric tons of greenhouse gas emissions.
In terms of economic benefits in the third quarter, Powerex led the way with $83.72 million, followed by the Los Angeles Department of Water and Power (LADWP) at $64.78 million and NV Energy with $60.3 million.
Building on the success of the WEIM, the California Independent System Operator and stakeholders are currently developing an Extended Day-Ahead Market (EDAM). This new initiative will enable WEIM participants to benefit from optimized and efficient commitments in the day-ahead market, a significant step toward meeting next-day energy demands, where the majority of energy transactions occur.