PSE to Join Energy Imbalance Market

Voluntary Wholesale Electricity Market to Generate Savings for Customers

BELLEVUE, Wash. (March 5, 2015) -- Puget Sound Energy announced today it will participate in an Energy Imbalance Market (EIM) operated by the California Independent System Operator (ISO) effective Oct. 1, 2016.

Voluntary participation in the EIM is expected to save PSE customers millions of dollars per year, increase reliability, improve integration of renewable resources, and create an efficient approach to carbon dioxide reduction. PSE’s customers could save between $18 million to $30 million a year through PSE’s participation in the EIM, according to a benefits study performed in 2014 by energy consultants Energy + Environmental Economics (E3).

In the Northwest today, wholesale electricity is bought and sold in hourly transactions. Over the past decade, an increase in renewable energy resources has made it challenging at times to cost effectively balance the system on an hourly basis because wind speeds driving the generators often vary minute-to-minute. This means having to use more expensive resources to balance the system until the next hourly market makes cheaper alternatives available. The new market and tools offered by the EIM provides access to a voluntary, liquid, within-hour market.

“The ISO Energy Imbalance Market will help us deliver the reliability and savings that are important to our electric customers,” said David Mills, PSE’s Vice President of Energy Operations. “Our studies show that participating in the ISO Energy Imbalance Market will help us enhance system reliability and offer economic savings through lower production costs.”

Benefits to Energy Imbalance Market

  • Efficient dispatch of PSE’s generating resources resulting in lower energy costs for our customers
  • Enhanced system reliability
  • Promotes integration of variable energy resources, such as wind and solar
  • Leverage geographic diversity of generating resources and electricity demand
  • Provides new, voluntary energy market that complements existing PSE operations

The projected benefits of PSE’s participation are bolstered by actual market results of the EIM elsewhere, which include the November 2014 experience between the California ISO and PacifiCorp. The ISO reported the actual market results in February showing that the EIM produced an estimated $6 million in benefits in just the first two months of operation.

Between now and Oct. 1, 2016, PSE will be working to upgrade generation dispatch and communication capabilities of its transmission and generation resources located within the PSE service area as well as working with the ISO, Federal Energy Regulatory Commission (FERC), and stakeholders to ensure a smooth launch.

“We are pleased Puget Sound Energy is moving to take advantage of the benefits the ISO’s western regional services can offer, which increase for all market participants as new companies enter the EIM,” said ISO President and CEO Steve Berberich.

Since 2012, PSE has also been participating in the Northwest Power Pool’s (NWPP) Market and Coordination Committee (MC) Initiative that is exploring a similar model based in the Northwest. PSE’s participation in the California EIM does not mean it has dropped its support of the regional NWPP MC efforts. Instead, PSE has elected to take a “dual path” approach and participate in the ISO’s EIM to generate economic and reliability benefits for PSE customers as quickly as possible, as well as continue to support development of the Northwest initiative.

About Puget Sound Energy

Puget Sound Energy is Washington state’s oldest local energy company. We serve 1.1 million electric customers and more than 770,000 natural gas customers in 10 counties. For more information, visit Also follow us on Facebook and Twitter.

Media Contact

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