Geological storage capacity for green excess energy readily available in Germany

摘要

Abstract. Energy supply in Germany is subject to a profound change.The present paper addresses the German potential of storing excess energyfrom renewable power sources in the geological subsurface. Wind and solarelectricity can be transformed into hydrogen, and with carbon dioxidesubsequently into methane. When needed, electricity is regained in a gasturbine power plant combusting the methane. Here, we are taking into accountthe actual German storage capacity for natural gas and show that theoutlined technology is ready for operation and economically competitive. Thecurrent potential for combined storage of methane and carbon dioxide allowsto store around 80 TWh renewable excess energy. This is far more thanrequired to date and estimated to provide the entire coverage in?2050.