How MISO is reforming market rules to spur storage deployment
Developers are eager to develop MISO’s storage market, but it has a long way to go to catch up with other RTOs
The Midcontinent Independent System Operator (MISO) is looking at ways to grow its storage market, but it could have a long way to go to rival the market in the neighboring PJM interconnection region.
MISO is the regional transmission organization that operates the wholesale electric power market in 15 Midwestern states and the Canadian province of Manitoba. The RTO already has a market for short and long term storage resources. Now, in response to several requests and queries, MISO is examining the feasibility of a medium term market, mostly for batteries, for durations of four hours or more.
“We are looking at ways to integrate that type of resource into the market and expand it,” said Jennifer Richardson, senior policy advisor for external affairs at MISO.
MISO first incorporated short-term storage into its tariff in 2009, with implementation in 2010. There is now about 400 MW of frequency regulation in MISO, most of which is served by thermal generating plants.
But while stored energy resources can participate in MISO’s regulation market, they cannot currently participate in the RTO’s other ancillary services markets such as spinning reserves, supplemental reserves or ramping products.
On Jan. 5, MISO held a workshop for stakeholders to examine the investment case for storage in the RTO. One of the questions that came up is whether storage should be categorized as generation or as transmission resources.
Transmission projects are paid differently than generation projects, and in a market like MISO it is possible that a storage project classified as transmission could fall under the jurisdiction of state regulators.
As it moves through its stakeholder process, Richardson said the RTO will remain “technology agnostic. We do not want to determine the path to success. MISO’s mission is to provide least cost energy solutions.”