Commercial grid scaling of Energy Bags for underwater compressed air energy storage

Abstract

Large-scale ability to store surplus energy for use during periods of high demand is a formidable asset in reducing the energy cost, improving electric grid reliability and addressing climate change. An Energy Bag is a fabric balloon-like vessel anchored to a sea- or lakebed for the purpose of storing surplus energy in the form of compressed air. This mode of energy storage is attractive because the passive pressure force of the deep-water environment takes on the significant role of pressure vessel structure to maintain pressurization of the air stored within the Energy Bag. Upon further investigation, it becomes evident that particular attention must be given to the storage volume and pressure required to satisfy requirements economically for commercial grid-scale development of this novel technology. This paper provides an introduction to the benefits and prerequisites pertaining to commercial scale energy storage capacity as related to Energy Bag structure, volume and deployment depth.