Cal-ISO: Seattle City Light agrees to participate in Energy Imbalance Market

The California ISO (Cal-ISO) on Dec. 12 said that Seattle City Light has signed an agreement to participate in the western Energy Imbalance Market (EIM) beginning in April 2019, becoming the first municipal utility to participate in the EIM.

The EIM is an optimization tool for utilities to balance supply and demand every 15 minutes with five-minute power plant dispatching, the Cal-ISO said, adding that utilities participating in the real-time market share resources more cost effectively across a larger geographic footprint, lowering the cost of delivering power to customers.

Saying that the EIM produces reliability benefits, operational efficiencies and cost savings for participants, Cal-ISO President and CEO Steve Berberich noted in the statement, “Increased participation leads to an increase in those benefits.”

Seattle City Light General Manager and CEO Larry Weis said in the statement that Seattle City Light has preliminarily evaluated the EIM from an environmental, commercial, and reliability perspective, adding, “I believe City Light’s participation can deliver benefits to our customers in all three areas.”

Among other things, Weis said, “This is the first in a number of steps to better integrate large-scale renewable resources in the west, and a new tool in our ‘tool belt’ to address climate change and set the foundation for a cleaner energy future.”

The Cal-ISO said that it will file with FERC the implementation agreement with Seattle City Light.

Other utilities set to the join the EIM include Portland General Electric on Oct. 1, 2017, and Idaho Power on April 1, 2018, the Cal-ISO said.

The Idaho Public Utilities Commission, for instance, on Dec. 2 said that it is taking comment through Dec. 15 on Idaho Power’s application to join the EIM, which, according to the commission, would allow Idaho Power to pool its generation with neighboring utilities to more accurately balance production to demand. Idaho Power claims that the move could reduce net power supply expense to customers by as much as $4m to $5m annually, the commission said.

Idaho Power, which hopes to join the EIM in April 2018, wants the commission to make a finding that its participation in the EIM could benefit customers in the long term; authorize a deferral account to track costs associated with participating in the EIM; and allow the company to recover those costs from customers in a future rate case, the commission said.

Among other things, the commission noted that there are upfront costs, estimated to be about $11.1m, which include start-up expense ($1.7m), software integration costs ($7.9m), and metering investment ($1.5m). There is also an ongoing operational expense of about $836,000 annually for labor and ongoing market and hosted software fees of about $786,000 annually beginning in April 2018. However, the commission added, Idaho Power claims that the net decrease in power supply costs would more than offset start-up and annual operational expenses.

The Cal-ISO said in its statement that the western EIM currently serves consumers in Arizona, California, Idaho, Nevada, Oregon, Utah, Washington, and Wyoming, adding that in the latest report analyzing the EIM’s benefits, participants saved almost $115m from November 2014 through September.

The Sacramento Municipal Utility District and Mexican grid operator El Centro Nacional de Control de Energía Baja Norte are currently exploring participation, the Cal-ISO said.

About Corina Rivera-Linares 3063 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 15 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at clinares@endeavorb2b.com.