Traditional hydro storage uses cheaper, off-peak electricity to pump water up hill, against the force of gravity. It stores the water in a dam up there, until a peak electricity demand period. Then the operator allows the force of gravity to release the water down hill, through turbines that generate electricity. A disruptive Texas startup is using hydro storage in an underground well, to generate electricity in an ‘upside down’ fashion.
What Has Underground Hydro Storage To Do With Batteries?
That’s a fair question, because this blog is all about batteries. A rechargeable battery stores electric energy from an outside source in its chemicals, so it can power an electrical device later.
A conventional hydro power station stores electrical energy in water that it pumps up hill. When the operator releases the water, gravity propels the liquid through turbines which regenerate the electricity.
The Quidnet model of hydro storage in an underground well, inverts that traditional hydro storage model. However, it is still a type of battery of a kind, because the energy storage dynamics are similar:
- The process begins with creating a pond of water, and drilling a water-storage well.
- Electric pumps feed the water down the well under pressure, when a utility grid has cheap, surplus electricity.
- The operator then closes the well, keeping the water under pressure. The hydro battery is charged!
- The operator waits for a peak demand period, when the utility purchases electricity at a higher price.
- The well operator then discharges the water battery. The pressure turns a turbine on the surface that generates electricity that feeds to the grid.
Proof of Underground-Well-Concept Trial
Quidnet Energy completed a successful trial of its hydro-hybrid battery concept on June 25, 2025. It opened its trial well after six months, and found the water pressure unaltered. The company then used this pressure to generate 35 megawatt hours of electricity.
So is this a long-duration ‘battery’ of a different kind? We believe it is, because it generated sufficient electricity to power an average North American home for over a month. This could be an attractive renewable energy option for businesses, or even communities at a larger scale.
More Information
Hydro Pumped Power and Batteries Merge
Hydro Global Battery Of The Future
Preview Image: Standard Quidnet Module Design
