Technological advances in the field of energy storage have been quite slow, especially compared to what has happened in terms of improving energy generation technologies. Batteries have been accused to slow down the transition from fossil fuels to renewables, as poor energy storage means call for a constant need of polluting back up generators.
But while most engineers and developers have focused solely on chemically-based technology, and more precisely Li-ion or its chemical alternatives, others have gone in a completely different direction.
Meet Hydrostor, the promising Canadian startup, who found a super effective, highly efficient, very cheap and most of all, zero-emission solution to the problem of storing energy. They decided to convert the excess power into compressed air and pump it into giant underwater balloons, to create the world’s first underwater compressed air energy storage system.
The balloons, known as accumulators, are placed at 55m depth near the shore of Toronto Island. They are made of material that is currently used to raise ships from the bottom of lakes and oceans, and are connected to the power plant with pipes. Excess electricity is converted into compressed air at the energy facility and transferred to the balloons for storage.
When needed, mostly during peak hours, the compressed air is pushed out of the balloons under the natural pressure of the lake water, and sent to a compressed air-powered turbine to produce electricity for the grid.
Such technology has not been widely adopted to date, not because of lack of feasibility, but rather because of the huge space it requires. Hydrostor found a solution to this problem by placing the balloons under water, and even took it a step further and used the water pressure to their advantage.
It has been two years since we first told you about Hydrostor’s energy storage system, but back then it was just a plan. Now it is real- the pilot facility, which can provide 660KW of power, began operation just a few days ago, on 18th of November. Although this amount of electricity is relatively modest, the guys at Hydrostor say that it is easily scalable. But the biggest advantage of the technology, which makes it much better than any battery technology, is that it is clean and does not use any toxic chemical substances.
The system is currently storing the excess energy during non-peak hours from Toronto’s power grid. In the future it will be adopted to serve the needs of solar and wind farms and store energy during hours when energy production is at its peak. Hydrostor is also looking into expanding globally and currently building a second underwater energy storage system in Aruba.
Image (c) Hydrostor