Swiss startup Power Vault got here out of stealth mode in 2018, and has been on an upward trajectory since then. The corporate created a system to retailer electrical energy by elevating concrete blocks, and buyers shortly jumped on board: Power Vault raised $110 million from the SoftBank Imaginative and prescient Fund in 2019, and one other $100 million led by Prime Movers Lab in 2021. It appears they’ve put that funding to good use, as a result of final week the corporate introduced commissioning of their first grid-scale vitality storage system outdoors Shanghai, China.
The system is sort of a strong model of pumped hydro, which makes use of surplus producing capability to pump water uphill right into a reservoir. When the water’s launched it flows down by generators, making them spin and generate vitality.
Power Vault’s strong gravity system makes use of enormous, heavy blocks fabricated from concrete and composite materials and lifts them up within the air with a mechanical crane. The cranes are powered by extra vitality from the grid, which may be created on very sunny or windy days when there’s not loads of demand. The blocks are suspended at elevation till provide begins to fall wanting demand, and once they’re lowered down their weight pulls cables that spin generators and generate electrical energy.
As a result of concrete is denser than water, it takes extra vitality to raise it, however which means it’s storing extra vitality too. The cranes are managed by a proprietary software program that automates most points of the system, from deciding on blocks to boost or decrease to balancing out any swinging movement that occurs within the course of.
The ability outdoors Shanghai has a capability of 100 megawatt hours (MWh); it may possibly constantly discharge 25 megawatts for as much as 4 hours. That’s comparatively small—for comparability’s sake, the Ludington pumped storage plant in Michigan has a capability of 1,875 megawatts, which might energy a group of about 1.4 million individuals. Power Vault says that subsequent gravity storage amenities it plans to construct will be capable to run at gigawatt-hour scale for 12 hours.
The Shanghai facility was constructed subsequent to a wind farm and a nationwide grid interconnection website. The corporate says the power could have a round-trip effectivity above 80 % (that means that 80 % of the vitality expended to elevate the blocks might be retained and translated to vitality output when the blocks are lowered). That’s similar to utility-scale batteries and pumped hydro.
One benefit the gravity system has over batteries, although, is that its storage capability will keep extra constant over time. Batteries slowly degrade as they cost and discharge, till they turn into unusable and will be recycled. The gravity system will probably have an extended lifespan than grid-scale batteries, and is extra appropriate for long-term vitality storage—that’s, storing extra vitality for weeks or months reasonably than hours or days. This sort of storage goes to turn into extra vital as we enhance our reliance on photo voltaic and wind energy.
Power Vault IPO’d in February of 2022 by a special-purpose acquisition firm deal. The corporate subsequently got here below hearth from analysts who mentioned its value and effectivity claims have been flawed. Later within the yr, a analysis agency revealed a brief vendor report concerning the firm, later retracting among the statements made. Power Vault’s inventory value plunged in mid-2022 and has but to recuperate.
These setbacks don’t appear to have deterred them an excessive amount of, although. They just lately signed an settlement to construct one other 100 MWh storage facility in China’s Hebei Province; they’re partnering with Pacific Gasoline and Electrical Firm to construct a 293 MWh facility in Northern California; and are constructing a 440 MWh facility close to Las Vegas.
Time will inform whether or not gravity storage is a possible possibility to assist us transition to renewables. Within the meantime, Power Vault says commissioning of the Shanghai facility might be full by the top of this yr.
Picture Credit score: Power Vault
