660 kW - Toronto Hydro - HydroStor Underwater Storage
Toronto’s Hydrostor founders Curtis VanWalleghem and Cameron Lewis unveiled their underwater compressed air energy storage (CAES) system on November 18. The system is located three kilometres off Toronto Island and will be used to stabilize Toronto Hydro’s grid during peak times. The energy storage system works by storing compressed air in a balloon-like structure 55 metres under Lake Ontario. When the energy is required the weight of the water is used to push the air to the surface through a pipe where an expander coverts the air back into electricity. At peak output the storage unit is capable of 660 kW, and is able to run for little more than a hour, depending on how much power is drawn.