Aecon Group Inc. (TSX: ARE) on 28 July 2026 announced that Simcoe Battery Project General Partnership Inc. — a consortium in which Aecon Concessions is an equity partner — has executed a 20-year Energy Storage Facility Agreement with Ontario's Independent Electricity System Operator (IESO) to build, own and operate the 150 MW / 1,200 MWh Simcoe Battery Energy Storage System in Norfolk County.
Who owns it, who builds it
The ownership group includes Aecon Concessions, Six Nations of the Grand River Development Corporation (SNGRDC), the Mississaugas of the Credit Business Corporation (MCBC), Sitka Power Inc. and NRStor. The consortium will collect IESO capacity payments plus revenue from energy sold into the Ontario grid and ancillary services. Aecon will also serve as the exclusive Engineering, Procurement and Construction contractor for the balance-of-plant works.
The Aecon storage flywheel
Simcoe is Aecon's fifth Ontario BESS after York, Goreway, South March, Trail Road and the operational Oneida project — the province's largest — which entered service in May 2025. Combined, Aecon-linked projects now represent roughly 1 GW of Ontario battery storage delivered or under delivery. "The Simcoe Battery Project will strengthen grid reliability and support the integration of renewable generation," Aecon Concessions president Steve Nackan said in the release.
Why 4-hour batteries, why now
At 150 MW / 1,200 MWh, Simcoe is an 8-hour battery — long-duration by North American standards, twice the four-hour benchmark for most current Ontario projects. That configuration is aimed squarely at capacity market payments and at absorbing evening peaks as Ontario retires or defers nuclear refurbishments and adds intermittent wind and solar. Target commercial operation date is 2030, matching the IESO's forecast supply gap. The Simcoe deal lands the same week that Ontario continues to reshape its long-duration storage procurement pipeline; it also lands in the middle of a global race for BESS capacity, with BYD's 11.3 GWh Abu Dhabi order and Aecon's own 1 GW Canadian book of business now anchoring the West's LFP supply chain.
Indigenous partnership at the core
SNGRDC and MCBC hold ownership stakes rather than the more common royalty structure, mirroring the Oneida model delivered by the Aecon-Six Nations (A6N) partnership. That structure has become the reference case for Indigenous-led Canadian energy infrastructure and is likely to keep showing up in the next wave of IESO procurements.
Reporting based on Aecon Group's GlobeNewswire release and IESO filings.