EIM quarterly results set new record; 15 balancing areas share over $132 million in benefits

By ISO Staff |

The Western Energy Imbalance Market (EIM) has released its second quarter benefits report for 2021 on Monday, August 2, and the results showed another new record in quarterly benefits - $132.7 million – bringing the total cumulative benefits over the past six years to $1.42 billion.

“During this dynamic period in the evolution of the Western energy landscape, the Western EIM has continued to gain momentum and deliver outstanding results,” said California Independent System Operator (ISO) President and CEO Elliot Mainzer. “As we drive for collaborative solutions to the challenging reliability issues that emerged from last summer and explore new approaches to governance, the ISO will continue working to help our market participants across the West realize even greater economic and environmental value.”

The report showed the measured benefits of participation in the Western EIM to include cost savings, increased integration of renewable energy, and improved operational efficiencies including the reduction of the need for real-time flexible reserves.

The Q2 2021 results exceed all previous quarterly benefits, defined as cost savings calculated from the optimization of market and grid efficiencies. The most recent results are due in part to widespread high temperatures in June, which increased activity in the real-time market, and the addition of seven new utilities located within four new balancing areas to the Western EIM’s market footprint.

Since its launch in 2014, the Western EIM has deployed sophisticated technology to find and deliver the lowest-cost energy to its members, while enhancing reliability and reducing emissions. The following table shows the 2021 second-quarter benefits for each participant:

(millions $)
Arizona Public Service$ 9.25
BANC$ 18.12
California ISO$ 27.58
Idaho Power$ 15.23
LADWP$ 8.54
NV Energy$ 6.20
NorthWestern Energy$ 1.06
PacifiCorp$ 15.05
Portland General Electric$ 7.45
Powerex$ 1.01
PNM$ 2.32
Puget Sound Energy$ 4.16
Salt River Project$ 12.61
Seattle City Light$ 2.75
Turlock Irrigation District$ 1.37
Total$ 132.70

The Turlock Irrigation District (TID) and the Balancing Authority of Northern California (BANC) Phase 2 joined the real-time energy market on March 25, which was one week prior to the end of the first quarter. The week’s worth of benefits accumulated by those entities at the end of that quarter are included in this quarter’s results.

Because of the renewable energy transfers supported by the Western EIM, there was a reduction in the need to curtail renewable energy resources during periods of oversupply. The avoided renewable energy curtailment for the quarter was 109,059 megawatt hours (MWh), resulting in a total of 1,509,114 MWh of avoided renewable energy curtailment since 2014.

In addition to the economic results, the report showed significant reductions in greenhouse gas (GHG) emissions because the regional market enables balancing authorities to share renewable resources, rather than curtail them, when an oversupply occurs. Cumulative GHG emissions have been reduced by 645,821 metric tons since 2014, which is the equivalent of removing more than 135,700 passenger cars from the road for one year.

The Western EIM’s real-time energy market experienced its largest increase in new participants earlier this year. The new entities include:

  • March 25: Turlock Irrigation District and BANC Phase 2 – which is comprised of Modesto Irrigation District, the City of Redding, the City of Roseville, and the Western Area Power Administration – Sierra Nevada Region
  • April 1: Los Angeles Department of Water and Power, and Public Service Company of New Mexico; and,
  • June 16: NorthWestern Energy

Operated by the ISO, the Western EIM footprint currently includes portions of Arizona, California, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming, and extends to the border with Canada. By 2023, 21 active Western EIM participants will represent over 78% of the load within the Western Electricity Coordinating Council (WECC).

Visit the Western EIM website for more information about participants, the market, quarterly benefits reports, and other information on its governance, upcoming meetings, and initiatives.

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