This story is part of a selection of our top news from 2025 that we’re republishing during the holiday break. We’ll be back to our regular schedule in the new year.
Previously posted: May 12, 2025
Canada’s biggest battery energy storage system went online ahead of schedule and under budget on a patch of industrial land just a few kilometres from the Six Nations of the Grand River in Ontario.
The 250-megawatt/1,000 megawatt-hour project in Haldimand County is co-owned by the Six Nations of the Grand River Development Corporation (SNGRDC), Northland Power, NRStor Inc., Aecon Concessions, and the Mississaugas of the Credit Business Corporation, all operating through the Oneida Energy Storage Limited Partnership (Oneida LP). It was originally priced at $800 million in 2023, but ultimately came in at $700 million, Northland Power said.
“With 278 lithium-ion battery units now officially drawing and storing power from Ontario’s electricity grid, Oneida LP will receive fixed capacity payments through a 20-year capacity services contract with Ontario’s Independent Electricity System Operator (IESO) and generate revenue from energy sold into the Ontario electricity grid, as well as from providing ancillary services to the system,” SNGRDC said May 7.
“Originally developed under a 50/50 partnership between SNGRDC and NRStor Inc., the Oneida Energy Storage facility serves as a model for meaningful partnerships, prioritizing Indigenous involvement in the development of clean energy in Canada,” the development corporation added. The project more than doubles Ontario’s energy storage capacity from 225 to 475 MW, will eliminate 1.2 to 4.1 megatonnes of climate pollution over its operating life, “and will support more efficient operation of traditional assets like gas and nuclear while furthering growth of renewable energy sources like wind and solar.”
The Oneida installation is now about 70% owned by Northland Power, the company said. The project received “significant funding” from Natural Resources Canada and the Canada Investment Bank and employed more than 180 Indigenous and Ontario workers during peak construction, including more than 40 through Aecon Six Nations, a majority Indigenous-owned firm.
“Oneida Energy Storage achieving commercial operation is symbolic to us on many levels,” SNGRDC President and CEO Matt Jamieson said in a release. “As a foundational partner we are especially proud to play a lead role in introducing grid-connected energy storage to the Ontario energy market. Not only does the project create value for Ontario ratepayers and our community, our involvement highlights the importance of Indigenous partnership and inclusion—it exemplifies what can be accomplished together.”
“Our partnerships-first approach to energy projects with Indigenous Peoples really enabled the Oneida vision to become a reality and also resulted in a true Canadian success story which serves as the model to replicate moving forward,” said NRStor Chair and CEO Annette Verschuren. “Today is a significant milestone for NRStor, our project partners, the Ontario government, and Canada’s clean energy future.”
“Oneida represents a pivotal step in our strategy to develop and operate battery storage facilities,” said Northland Power President and CEO Christine Healy. “Delivering this project ahead of schedule and under budget is a clear demonstration of Northland’s capability to execute large-scale energy projects safely and effectively.”
Last month, Energy Storage News cited Oneida as the “flagship” for nearly three gigawatts of battery storage that will be going into service in Ontario. It says the IESO will account for about 60% of the project’s revenue.
On LinkedIn, Royal Bank of Canada Senior Vice-President John Stackhouse described Oneida as “a really big deal” that “may soon become a model for big demand users (hello, data centres) as they explore options.”
