Texas-based startup Quidnet Vitality simply accomplished a check displaying it might retailer power for as much as six months by pumping water underground.
Utilizing water to retailer electrical energy is hardly a brand new idea—pumped hydropower storage has been round for over a century. However the firm hopes its twist on the know-how may assist convey low cost, long-duration power storage to new locations.
In conventional pumped hydro storage amenities, electrical pumps transfer water uphill, right into a pure or artifical physique of water. Then, when electrical energy is required, that water is launched and flows downhill previous a turbine, producing electrical energy. Quidnet’s strategy as a substitute pumps water down into impermeable rock formations and retains it beneath stress so it flows up when launched. “It’s like pumped hydro, the other way up,” says CEO Joe Zhou.
Quidnet began a six-month check of its know-how in late 2024, pressurizing the system. In June, the corporate was capable of discharge 35 megawatt-hours of power from the effectively. There was just about no self-discharge, that means no power loss, Zhou says.
Cheap types of power storage that may retailer electrical energy for weeks or months may assist inconsistent electrical energy sources like wind and photo voltaic to go additional for the grid. And Quidnet’s strategy, which makes use of commercially obtainable gear, could possibly be deployed shortly and qualify for federal tax credit to assist make it even cheaper.
Nonetheless, there’s nonetheless a giant milestone forward: turning the pressurized water again into electrical energy. The corporate is at the moment constructing a facility with the generators and help gear to try this—the entire elements can be found to buy from established firms. “We don’t have to invent new issues primarily based on what we’ve already developed immediately,” Zhou says. “We will now begin simply deploying at very, very substantial scales.”
That course of will include power losses. Vitality storage programs are sometimes measured by their roundtrip effectivity: how a lot of the electrical energy that’s put into the system is returned on the finish as electrical energy. Primarily based on modeling, Quidnet’s know-how may attain a most effectivity of about 65%, Zhou says, although some design decisions made to optimize for economics will possible trigger the system to land at roughly 50%.
That’s much less environment friendly than lithium-ion batteries, however long-duration programs, in the event that they’re low cost sufficient, can function at low efficiencies and nonetheless be helpful for the grid, says Paul Denholm, a senior analysis fellow on the Nationwide Renewable Vitality Laboratory.
“It’s received to be cost-competitive; all of it comes right down to that,” Denholm says.
Lithium-ion batteries, the quickest rising know-how in power storage, are the goal that new types of power storage, like Quidnet’s, should chase. Lithium-ion batteries are about 90% cheaper immediately than they have been fifteen years in the past. They’ve change into a price-competitive various to constructing new pure fuel vegetation, Denholm says.
In terms of competing with batteries, one potential differentiator for Quidnet could possibly be authorities subsidies. Whereas the Trump administration has clawed again funding for clear power applied sciences, there’s nonetheless an power storage tax credit score, although lately handed laws added new provide chain restrictions.
Beginning in 2026, new power storage amenities hoping to qualify for tax credit might want to show that at the very least 55% of the worth of a venture’s supplies aren’t from international entities of concern. That guidelines out sourcing batteries from China, which dominates battery manufacturing immediately. Quidnet has a “excessive stage of home content material” and expects to qualify for tax credit beneath the brand new guidelines, Zhou says.
The power Quidnet is constructing is a venture with utility accomplice CPS Vitality, and it ought to come on-line in early 2026.
