Isothermal Deep Ocean Compressed Air Energy Storage: An Affordable Solution for Long-Term Energy Storage

Abstract

The world is undergoing a substantial energy transition with an increasing share of intermittent sources of energy on the grid such as wind and solar. These variable renewable energy sources require an energy storage solution to allow a smooth integration of these sources. Batteries can provide short-term storage solutions. However, there is still a need for technologies that can provide seasonal energy storage at locations without the potential for pumped hydro storage. This paper presents innovative solutions for energy storage based on isothermal air compression and storage of the air in the deep ocean. The cost of isothermal deep ocean compressed air energy storage (IDO-CAES) is estimated to vary from 1 to 10 USD/kWh of stored electric energy and 1,500 to 3,000 USD/kW of installed capacity. IDO-CAES could be a feasible option to complement batteries, providing long-term energy storage cycles.

Keywords: cost-benefit analysis, long-term energy storage, electricity storage innovation, compresses air energy storage, sustainable development, carbon-neutral world