Ocean Battery

The Ocean Battery is a modular pumped hydro energy storage system deployed offshore to store renewable energy. It utilizes water as the storage medium in a process analogous to conventional hydropower dams. The system consists of rigid reservoirs on the seafloor connected via pipelines to flexible rubber bladders, also on the seafloor. To store energy, electric pumps move water from the rigid reservoirs into the bladders, pressurizing the water. The gravitational potential energy of the pressurized water is the stored energy. When electricity is needed, valves open allowing water to flow from the bladders back into the reservoirs. This water spins hydraulic turbines coupled to electric generators, producing electricity. The modular and scalable design allows the Ocean Battery to provide utility-scale energy storage capacity up to the GWh level. The system has a round-trip efficiency of up to 80% and an operational lifetime of decades. By storing renewable energy offshore near its source, the Ocean Battery can help balance fluctuations in supply and demand on electrical grids.