By Robert Mullin
California’s oldest irrigation district has become the latest balancing authority to commit to the Western Energy Imbalance Market.
CAISO said Wednesday that Turlock Irrigation District (TID) signed an agreement to join the EIM in April 2021, putting it on track to begin trading alongside Los Angeles Department of Water and Power, NorthWestern Energy and Public Service Company of New Mexico.
TID’s decision comes just a week after Arizona-based Tucson Electric Power said it will link up with the real-time market in 2022. (See Tucson Electric Power Signs up for Western EIM.)
Established in 1887 to provide water to farmers in California’s Central Valley, TID now serves more than 100,000 electricity accounts in addition to 5,800 irrigation customers. The district’s generation portfolio includes 137 MW of wind, 98 MW of natural gas, 54 MW of contracted solar, a small amount of geothermal and a 68% share of the output from the 203-MW Don Pedro hydroelectric dam.
TID also owns a share of the California-Oregon Intertie, the key link between the Pacific Northwest and Northern California. Its transmission network interconnects with neighboring systems operated by CAISO, the Western Area Power Administration, the California-Oregon Transmission Project and the Sacramento Municipal Utility District (SMUD), the last of which began transacting in the EIM last month.
“TID’s participation in the Energy Imbalance Market will lead to a greater utilization of our resource portfolio,” Brad Koehn, the district’s assistant general manager of power supply, said in a statement. “Additionally, gaining access to the resource diversity within the EIM footprint will help us maintain our core mission of providing reliable and affordable power.”
The sheer momentum of the EIM — combined with a parallel decline in regional bilateral markets — appears to have sealed the deal for TID.
“With the amount of utilities participating in the intra-hour market, TID expects the hourly markets it currently participates in will become much less liquid compared to previous years. Over time, this reduced liquidity would likely lead to increased purchased power and fuel costs, absent participation in the EIM,” TID said last month in announcing its plans.
TID estimates it will recoup its $5.5 million in EIM start-up costs in two to three years.
The EIM’s current members in addition to SMUD are Arizona Public Service, Idaho Power, NV Energy, PacifiCorp, Portland General Electric, Puget Sound Energy and Powerex. CAISO last month said the EIM has yielded $650.26 million in benefits for its members since being launched with PacifiCorp as its first member in November 2014.