NorthWestern seeks to join Western Energy Imbalance Market

NorthWestern Energy recently announced that it plans to join the Western Energy Imbalance Market (EIM), which is operated by the California Independent System Operator (CAISO), by April 2021.

NorthWestern cited lower costs, more efficient use of renewable energy and greater power grid reliability as reasons it intends to join the EIM.

“The EIM will allow NorthWestern to make better use of our transmission and electric generation resources,” NorthWestern Energy CEO Bob Rowe said. “Expanding our use of the regional electric grid through the EIM will help integrate variable renewable energy. We have seen significant growth in wind generation in Montana, which highlights the need to have access to other generation resources that are available on demand, 24/7. Being part of EIM will help with that need.”

The EIM is a real-time energy market that uses software to analyze regional power grid needs and makes low-cost generation to meet demand every five minutes. It enables participating electric companies to automatically use the most economical generating option available to meet short-term variations in customer power use. The market also makes it easier to integrate variable renewable output with other resources.

“Participating in the EIM will help ensure that NorthWestern’s electric generating resources are used in the most economic manner possible,” John Hines, vice president of supply for Northwestern said. “Participation will also allow NorthWestern customers to benefit from lower-cost generation owned by other utilities and power producers in the western region.”