EllisDon Partners with Cache Power for Canada’s First Compressed Air Storage Facility

MISSISSUAGA, ON, December 02, 2025 — EllisDon has partnered with Cache Power to deliver Canada’s first commercial scale Compressed Air Energy Storage (“CAES”) facility in Northeast Alberta; a groundbreaking project that will set a new benchmark for long-duration energy storage.

The storage facility will be built in two phases and strategically positioned beside the Marguerite Lake substation to maximize efficiency and grid integration. CAES offers a cost-effective, long duration solution essential for managing renewable, intermittent energy sources. This technology will play a critical role in stabilizing Alberta’s grid and advancing both provincial and national commitments to a net-zero electricity future. The project has received all major regulatory approvals, with early construction to begin in Q4 2025.

“EllisDon is proud to invest in and partner with Cache Power on Canada’s first commercial scale Compressed Air Energy Storage facility,” said Joey Comeau, Chief Operating Officer & Executive Vice President, Capital, EllisDon. “This project proves the confidence EllisDon and the market have in long-duration storage as a cornerstone of a reliable, low-carbon energy future. With a multi-phase design, the project aims to shine a spotlight on renewable energy while creating strong project economics for future partners and investors.”

Based on Siemens Energy technology, CAES is a mature and proven technology solution, capable of providing ultra-long-duration energy storage (48 hours) at a lower capital cost compared to other storage technologies. No comparable storage project of this size and duration exists in Alberta.

EllisDon is looking forward to working with Siemens Energy and growing our relationship through the implementation of the Marguerite Lake CAES Project.

“This partnership is an important step toward storing and re-using energy reliably and responsibly. CAES is a mature—though not yet widely adopted— technology built on high-quality, long-proven components like our compressors, turbines, and generators. We are proud to partner with EllisDon who shares our pioneering mindset. Together, we will turn innovation into reliable daily performance,” said Tobias Panse, Senior Vice President, Industrial Steam Turbines & Generators, Siemens Energy.

“Alberta is setting the pace for Canada’s clean energy future and commitment to encourage renewable energy growth in the province,” said David McFarlane, Chief Operating Officer & Executive Vice President, Construction, Western Canada, EllisDon. “Together with our partners, we’re building a resilient, low-carbon energy system that creates lasting economic and social value for local communities and Indigenous partners.”

The facility will store up to 48 hours of energy by compressing air using surplus electricity from the grid and storing it in underground solution-mined salt caverns. During periods of higher demand, the air is released and mixed with natural gas to generate heat, allowing it to expand and drive turbines to generate electricity. The system can blend up to 75% hydrogen with natural gas, with a pathway to full hydrogen use, supporting Canada’s net-zero goals. Babcock & Wilcox have partnered on engineering the potential hydrogen facility addition, utilizing its BrightLoopTM technology.

The project is committed to delivering economic and social benefits to local communities and Indigenous Partners. Cold Lake First Nations has taken an active role in the development of the project and is expected to participate as a partner with Cache Power Corp in the project and operations.

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MEDIA CONTACT

Amanda DiPasquale
Manager, Communications
EllisDon Corporation
adipasquale@ellisdon.com / 942-388-8308

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