As California moves towards its objective of achieving 100% carbon-free electricity by 2045, it will require large-scale, long-duration storage in order to more fully integrate increasing levels of renewable generation capacity.
A Canadian cleantech company Hydrostor provides a cost-effective, emissions-free storage solution. The company has announced the development of 1,000 MW of long-duration energy storage in California using its patented A-CAES (Advanced-Compressed Air Energy Storage) technology.
It has two major projects now in active development – one in southern Kern County and one in Central California. Each of the two projects, each with 500 MW/5 GWh capacity, is the largest non-hydro pumped energy storage project in the world. In total, it will provide 1GW/10GWh of long-term storage.
A-CAES uses renewable energy or surplus electricity from the grid to run an air compressor. This compressed air is then stored inside a purpose-built underground tank, displacing the water and creating storage capacity. It is released through a turbine to generate electricity that’s fed back into the grid. The heat created by this process is captured and stored in a separate thermal storage tank, and the Hydrostor’s system uses to reheat the air as it’s fed in to the turbine stage. As a result, compressed air storage systems have typically offered round-trip efficiencies between 40-52%, but for this system, it’s going to be around 60%.
Hydrostor’s patented and commercially proven A-CAES advanced compressed air technology provides 8 to 12 hours or more of energy storage, compared to 1 to 4 hours that current battery technologies can feasibly provide. This long-term energy storage is essential in paving the way for California’s decarbonized power grid. A-CAES also has a longer useful life, of more than 50 years, with zero degradation and a lower environmental impact than the conventional alternatives available today.
“Long-duration storage is essential for decarbonizing the California electricity grid and integrating the renewable energy that is already developed in the state,” said Curtis VanWalleghem, CEO, Hydrostor. “Our A-CAES technology utilizes only existing, proven components that are repurposed from conventional power generation into an entirely emissions-free and low impact storage technology. Not only are we providing a clean, reliable, and affordable long-duration energy storage solution, but we’re also providing Californian workers and suppliers a more direct opportunity to be part of the clean energy transition.“
Classic battery storage systems are only suitable to a limited extent. That is why solutions like those from Hydrostor are an important next technology of the energy transition, especially in the USA, UK, and Australia – and soon also in Central Europe, which currently still has the advantage of the interconnected network.