"A Toronto company is about to launch the world’s first underwater compressed air electricity storage system – a technology that could add to the range of storage options and help renewable power gain wider acceptance.
Hydrostor Inc. will formally put the system into service on Wednesday. It is hooked up with the electrical grid through the local power distributor, Toronto Hydro, which will test how well it stores electricity over the next two years.
The system uses electricity to compress air in a building on Toronto Island, just off the city’s downtown. The air is then pumped through a pipe into six large balloons anchored on the lake bed about three kilometres offshore, 60 metres below the surface. The weight of water keeps the balloons pressurized."
Read the story in the Globe and Mail