Storing renewable energy sustainably and efficiently is one of the major challenges of our time. A team of German researchers is proposing a revolutionary solution: concrete spheres immersed in the ocean floor. Their potential is such that California is preparing to test a large-scale prototype.
A Simple, Ingenious Concept
The project, called StEnSea (Stored Energy in the Sea), was developed by the Fraunhofer IEE (Institute for Energy Economics and Energy Systems Technology). The idea is relatively simple: hollow concrete spheres are installed at a depth of several hundred metres. Each sphere is fitted with a pump-turbine and a valve system.