Around one-fifth of global greenhouse gas emissions are caused by heating and cooling. The demand for cooling in particular will rise sharply in the future. However, only a small proportion of the energy required for this currently comes from renewable sources. Researchers at KIT and its partners have now conducted a study to investigate the economic viability of aquifer storage. This involves storing cold or warm water in natural aquifers and extracting it at times when the corresponding temperature energy is needed.

For their study, the scientists analyzed data from 132 plants and compared it with the investment costs for other thermal energy storage systems and geothermal systems, such as geothermal probes.

“We were able to prove that aquifer storage is the most cost-effective thermal storage technology and should therefore be the preferred option under suitable hydrogeological conditions,” says Professor Philipp Blum from the Institute of Applied Geosciences at KIT, one of the initiators of the study. “However, many countries, including Germany, have hardly used aquifer storage to date. There is considerable potential for expansion here.” He advises integrating seasonal geothermal energy storage systems into municipal heat planning. “In Germany, over 50 percent of the area is suitable. The potential of this storage technology is therefore enormous,” says Blum.