An innovative energy storage technology is gaining traction in Alberta as a way to deal with the intermittent nature of energy from renewables such as wind and solar.As Alberta transitions to sourcing ever-increasing amounts of renewable energy for electricity generation, energy storage will be "the next frontier," says Robert Stewart, vice president of Alberta-based Rocky Mountain Power.He explains: "Wind power is currently the lowest cost of new electricity generation. But the wind doesn't blow predictably. There must be a way to store the energy generated by wind farms for days to provide the certainty of our current electrical system with low cost wind energy."Rocky Mountain Power believes it has a solution: compressed air energy storage (CAES). When wind farms are generating electricity that is of low value to the system, a CAES plant can use that electricity to compress air and store it in an underground cavern. When electricity is of higher value, the plant releases the stored compressed air into a series of turbines to produce electricity.Their project is called the Alberta Saskatchewan Intertie and Storage (ASISt) project; it is managed by Rocky Mountain Power's subsidiary SATL Inc. Planned for the Lloydminster region, the facility will take advantage of excellent geology for cavern development as well as easy access to both the Alberta and Saskatchewan electrical grids. It would also leverage the significant oil and gas expertise both in the area and province-wide. ASISt would be the world's first CAES facility to commercially integrate renewables.Alberta Innovates supported the project with funding for a feasibility study that was completed in late 2018. "We're now sharing this information with potential customers," says Stewart. "It is a vital step toward securing commercial support for the project and allowing us to move forward with engineering. Without the Alberta Innovates funding we wouldn't be at this stage."Photo courtesy of Agata Kdziorek via Unsplash