The Oneida BESS is a 250 MW/1,000 MWh battery energy storage system that is able to store electricity generated from any source, including baseload power from nuclear and hydro and more intermittent power from wind and solar. Situated on a 10-acre site and connected to Hydro One’s transmission grid, it consists of a 230 kV step-up substation and houses 278 lithium-ion battery containers that collectively store enough energy to power approximately 410,000 homes. The system nearly doubles the battery energy storage capacity in Ontario’s clean electricity grid from approximately 225 MW to approximately 475 MW. This project is the largest of its kind in Canada and supplies Ontario with clean and reliable electricity while eliminating up to 4.1 million tonnes of greenhouse gas emissions per year—comparable to taking 40,000 cars off the road.
A model for partnership with Indigenous Peoples
With Six Nations of the Grand River as a co-owner, the project is a model for future large-scale energy projects on Indigenous territory. It also puts into practice the Business and Reconciliation recommendation of the Truth and Reconciliation Commission of Canada: Calls to Action report. Subcontracting opportunities during construction, full-time employment for the operation of the system, and internship training opportunities.
Greening the province’s energy grid and enhancing energy security
Through its connection to the Hydro One transmission grid, the system stores electricity from several clean energy sources, including nuclear, hydro, wind and solar. The stored clean energy is then released when the demand is greater, cutting down emissions by 1.2 to 4.1 million tonnes of CO2 annually. The system will also provide energy security in Ontario, where electricity demand is expected to triple in the near future because of factors like population growth and electrification of transportation.