Bonneville Power Administration, Tucson Electric Join Western Energy Imbalance Market

The California Independent System Operator Corp. on May 3 announced that  the Bonneville Power Administration and Tucson Electric Power have joined the Western Energy Imbalance Market, or WEIM. Enrolling with the WEIM allows both utilities the opportunity to achieve cost saving and lower carbon emissions for their customers. Moreover, participating in the market provides another avenue to increase their use of wind and solar energy.

The WEIM employs advanced technology to locate and distribute the least cost energy to its participants, while improving dependability and giving considerable environmental advantages through the reduction of renewable energy curtailments during intervals of excess supply.

As of April 21, 2022, the WEIM is reported to have provided more than $2 billion in cumulative benefits for entities participating and  reduced greenhouse gas emissions by more than 700,000 metric tonnes since the market launched in 2014.

Avista Utilities and Tacoma Power began their participation in the WEIM in March. The two utilities serve a combined 600,00 electric customers in the Pacific Northwest. The WEIM now has 19 participants who provide increased reliability and significant environmental gains through the real time transfer of energy. The uptick in solar and wind generation on the electricity grid, would usually go underutilised to prevent the grid from being overused, however with the greater regional management by the WEIM, the excess clean generation can be moved across a geographic location to replace other resources. The market currently serves 77 percent of the demand  for electricity in the Western U.S.

Currently, the California grid operator  is cooperating with utilities, independent power producers, regulators, environmental advocates, and other associates to create an Extended Day-Ahead Market, or EDAM. The optimisation of varied generation resources and transmission on a day-ahead basis across the WEIM’s geographic operational footprint would allow market members and buyers to achieve enhanced dependability, monetary and environmental benefits.

The ISO will be taking comments on the market design through early June and will carry on operating keenly with stakeholders across the West to conclude the design this year. As it stands, the implementation testing is expected to be in 2023 and onboarding the first set of EDAM participants in early 2024.