Abandoned oil and gas wells may soon have a new purpose: energy storage.

The technique is called pumped hydro, and it’s the same approach used in conventional hydroelectric dams.

Mandell: “Pumped hydro is not new. It’s the oldest and most widely available form of energy storage today. What we’re doing is basically a new form of pumped hydro, where all of the infrastructure, and all of the energy storage actually happens below the ground.”

That’s Aaron Mandell, chairman and co-founder of the start-up Quidnet Energy.

Quidnet proposes storing energy in old wells by filling them with water at very high pressure. As the pressure increases, rock below the surface compresses like a spring. When the water is discharged, the pressure is released, pushes the water through turbines, and creates electricity.

Mandell says the system may need to be tailored for different geologies, but it should work anywhere.

Quidnet has demonstrated its concept with a gas well and is now testing in a geothermal well. Mandell says the results of this test will determine if they will move on to a commercial installation capable of storing five to 10 megawatts of energy.

If successful, hydro-pumping may give new purpose to abandoned wells, and be a cost-effective way of storing wind and solar energy.

Reporting credit: Pam Memmott/ChavoBart Digital Media.
Image graphic credit: Created by David McCarthy.