Toronto Hydro is teaming up with Toronto startup Hydrostor to launch the world’s first underwater energy storage system. Three kilometres off Toronto Island and located 55 metres underwater, Hydrostor's system is connected to Toronto Hydro's electricity grid, and uses compressed air and the pressure of water to run its system. The technology works by running electricity through a compressor and converting it into compressed air. The compressed air is sent underwater where it is stored in large balloon-like structures, made out of the same type of material used in marine lift bags to raise shipwrecks. When electricity is needed again, the weight of the water pushes the air to the surface through a large pipe and an expander converts the air back into electricity.
“ As this technology is a world first, we’ll be evaluating the system’s versatility during the pilot project under real world operating conditions,” says Jack Simpson, director of generation and capacity planning. “
The technology has the potential to create a new generation of clean energy, as it produces zero emissions and stores electricity during off-peak hours when demand is low and electricity is cheapest. The electricity can then be released again during short-term power outages or high-demand times.
“In these situations, the HydroStor system would be able to release stored energy and provide the grid with an additional resource to help limit peak energy prices, improve power quality and help restore power during an area outage,” says Simpson.
It will remain there until a two-year pilot study is complete.