Dive Brief:

• The city council of Goderich, Ontario, has approved a proposal by NRStor for a 1.75 MW, 7 MWh compressed air energy storage (CAES) plant.

• The project would pump air into an unused salt cavern during off peak hours and generate electricity by using the stored during times when electricity is in greater demand and more expensive.

• Unlike other CAES projects, the NRStor Goderich project would use technology developed by Hydrostor that captures heat from compressing the air in order to avoid using natural gas.

Dive Insight:

One of the advantages of CAES technology is its ability to provide long duration energy storage solutions.

NRStor’s Goderich project would be able to discharge energy for up to four hours. The project also would use technology that strips the heat from compressing air and stores it in a thermal heat exchanger developed by Hydrostor. The stored heat is then used as the compressed air is discharged to turn the turbines that power the generators.

With a traditional CAES project the air would have to be heated to power the turbines, typically using natural gas. 

Hydrostor’s heat exchanger is one element in another CAES technology Hydrostor is developing. The Toronto company compresses air into water reservoirs to stabilize the pressure and improve efficiencies.

It is developing variants of that technology. One stores the air in underwater balloons, the other stores the air in underground caverns.

The Goderich project only uses Hydrostor’s heat exchanger, but that still means it is able to store and discharge energy without creating any emissions.

Katherine Peretick, NRStor’s director of engineering, said the Goderich project would be the first fuel-free CAES project in the world.