In the summer of 2021, a flurry of R&D money was flying into new long-duration energy storage technologies. The influx aligned with the Biden administration’s new Earthshot Initiative, which aimed to push down the cost of long-duration energy storage by 90 percent by 2030.
Now, a year and a half later, it seems some of those technologies are transitioning into projects, with real money backing them.
The deployments are meaningful. It reflects that the technologies are maturing, and we’re getting a little closer to figuring out how to power the economy on clean energy all day, every day.
Here’s a roundup of some projects getting headlines already in this young year.
Compressed air in California’s San Joaquin Valley
Last week, a group of local governments in California signed a $775 million, 25-year contract to purchase power from what will be the world's largest compressed-air energy storage project, reports the Los Angeles Times. The project, set to be ready by 2028, will be in the San Joaquin Valley.
Here’s how it works: Developers will drill three shafts thousands of feet below ground, and send miners to dig out a series of caverns. These caverns are meant to have a collective volume equivalent to the area of two football fields by 100 yards of height. This project would be the first compressed air storage enterprise that doesn’t rely on naturally occuring underground salt domes.
When clean electricity is cheap (like sunny afternoons — think belly of the duck), the developer, Hydrostor, will use low-cost energy to push air down into the caverns. When Hydrostor’s customer, Central Coast Community Energy, needs to draw on the stored power, the company will open a valve and funnel the high-pressure air through a turbine, generating electricity.
Green hydrogen in Northern California’s wine country
Further north, Pacific Gas and Electric (PG&E) and Energy Vault announced a partnership to build and operate the largest green hydrogen long-duration energy storage system in the US. The hybrid system will be capable of powering about 2,000 electric customers on a PG&E microgrid in Calistoga for up to 48 hours (293 MWh of carbon-free energy) during an outage.
Here’s how it works: The system will produce green hydrogen by using renewable energy to power electrolysis, a process that creates hydrogen from water. The clean hydrogen will then power a fuel cell to create on-demand energy. The system is outfitted with a short duration battery for grid forming and black start capabilities, meaning it is able to restart parts of the power system to recover from a blackout.
The project is being considered for approval from the California Public Utilities Commission. If authorized, it could provide some much-needed resilience to the Calistoga region (which is affected by utility shut-offs to reduce the risk of wildfires), and serve as a model for Energy Vault’s future utility-scale hybrid storage system deployments.
Taking the hard-to-mine metals out of energy storage
This week, Noon Energy announced it secured $28 million in Series A financing to commercialize its carbon-oxygen battery technology for long-duration energy storage. While the company is at an earlier stage than the previously mentioned projects, the technology promises 100-plus hours of storage at a cost 10x lower and an energy density 3x higher than current lithium-ion batteries, according to a release.
Here’s how it works: Developed by a scientist on NASA’s Mars rover team, the technology uses electricity to split carbon dioxide into solid carbon and oxygen gas. To discharge, it reverses the operation, oxidizing the solid carbon, reports Canary Media. The result is a battery that uses "nature-based chemistry principles" and eliminates the need for mined lithium and cobalt. According to the company, the technology only requires 1 percent of other critical metals compared to conventional lithium-ion batteries.
The funding will enable Noon Energy to accelerate the path to market through critical demonstrations and field deployments while growing its engineering, product and business development teams.