Switzerland Is Building One Of History's Most Powerful Batteries 100 Feet Underground

There's a massive 88-foot-deep hole in Switzerland that will house the world's most powerful redox flow battery. This battery storage system, which is being built by FlexBase, covers more than 215,000 square feet and is part of a billion-dollar project that intends to stabilize Europe's power grids and prevent blackouts. This battery system — which will get its power from excess energy generated by wind turbines — has a capacity of 2.1 GWh, enough energy to power around 210,000 households for an entire day.

Redox flow battery systems help compensate for the fluctuating amounts of electricity generated by renewable methods by storing additional electricity and releasing it when needed. These batteries use liquid electrolytes rather than the usual lithium-ion batteries you find in laptops and phones. The batteries store these liquid electrolytes in large tanks, with stacks of electrochemical cells above them that will convert the stored energy into electricity.

While this massive underground battery storage system may be the most powerful, it's not the first and it definitely won't be the last. Batteries have become a major part of Switzerland's energy mix, with the number of batteries installed in homes and businesses increasing by over 400% from 2021 to 2024, according to a Swissolar report. They are becoming crucial to help reduce the risk of power outages, which is especially important given the rising energy use of technologies such as artificial intelligence.

Redox flow batteries are on the rise throughout Europe, but Asian countries have been using the tech for quite some time. Japan is leading the way in the region, but China and South Korea are also well ahead of Europe in this regard as well. Japan, for its part, aims to be carbon neutral by 2050, with redox flow batteries as part of the solution by helping store clean energy from the country's massive solar power expansion over the past few years. Japan has also dabbled in some innovative ways to produce this clean energy, including seawater osmosis and piezoelectric tiles that generate electricity from footsteps.