German energy company wants to build flow batteries in old natural gas caverns
A German energy company recently announced that it’s partnering with a university to build a massive flow battery in underground salt caverns that are currently used to store natural gas.
The grid-tied battery, the company says, would be able to power Berlin for an hour, Arstechnika reports.
The technology that the project is based on should be familiar to Ars readers. Two years ago, Ars wrote about an academic paper published in Nature that described “a recipe for an affordable, safe, and scalable flow battery.” German researchers had developed better components for a large, stationary battery that used negatively and positively charged liquid electrolyte pools to exchange electrons through a reasonably priced membrane. These so-called “flow batteries” are particularly interesting for grid use—they have low energy-density, so they don’t work for portable energy storage. But as receptacles for utility-scale electricity storage, their capacity is limited only by the amount of space you have.
Now the ideas in that paper are graduating to real-world use. EWE Gasspeicher, a gas-storage company owned by German power company EWE, announced in June that it’s looking into building the researchers’ flow battery in two medium-sized salt caverns that the company has been using to store natural gas. EWE is calling the project “brine4power,” reflecting how a saltwater brine is used in the electrolyte.
