Underwater rock tunnel energy storage device

Could energy bags be used to store electricity underwater?

In the Bag: Energy bags like this 5-meter-diameter one, from Thin Red Line Aerospace, of Canada, could be used to store electricity underwater as compressed air. Engineers hope the technology could one day smooth out the intermittency of electricity produced by offshore wind farms and other renewable energy sources.

What does Garvey think about underwater storage?

Garvey sees the underwater storage as part of a holistic system. “An offshore wind farm should not simply be a subsystem that produces electricity when the wind blows. It should be a system which takes energy from the wind and does whatever is needed to deliver energy to shore as that [energy] is needed.”

What is an underwater pumped hydro storage system?

The basic concept of an underwater pumped hydro storage system is not dissimilar from that of its land-based cousin. The difference is all in the details of how you make electricity by pumping water around when you’re already under the sea. The general idea is to have a closed vessel sitting on the seafloor.

Are underwater reservoirs scalable?

Installation is readily scalable, too. Each underwater reservoir only needs an electrical connection to the grid, and nothing more. Simply installing more reservoirs underwater with the appropriate electrical infrastructure will easily scale up the capacity of such an installation.

How much energy can a water reservoir store?

The company expects that one reservoir, with a capacity of 20 million liters of water, could store up to 10 MWh of energy. The Ocean Grazer project, which won an award at CES 2022 , is perhaps receiving the greatest press for underwater pumped hydro at the moment.

Why is running underwater a good idea?

Running underwater also allows the system to take advantage of the great pressure exerted by the sea above. For each 10 meters of depth, pressure increases by roughly one atmosphere (1 bar), and with a system designed to operate with vessels at near-vacuum when fully “charged”, there’s a huge differential to take advantage of.