Chances and risks of aquifer thermal energy storage (ATES) systems

Decarbonising the heating and cooling sector is crucial for reducing our global CO₂ emissions. One promising option for environmental friendly energy supply in buildings is the use of shallow geothermal energy (SGE) (< 400 m depth) such as ground source heat pump (GSHP), groundwater heat pump (GWHP) and tunnel geothermal systems. In addition, renewable energy sources such as wind and solar are typically intermittent in nature, which is why they are characterized by an abundant but limited instantaneous availability. Peak time shaving and shifting by thermal energy storage are therefore considered as a key to the transition of the heating and cooling sector from fossil-based to zero-carbon. To balance these temporal variations in the availability and demand, Underground Thermal Energy Storage (UTES) systems could be used. In particular, Aquifer Thermal Energy Storage (ATES) systems are characterized by high storage capacities and low storage costs and is, therefore, drawing growing attention worldwide. However, only little is known about global application and distribution of ATES systems. Hence, this talk will provide an overview of the present and future potential of ATES systems including the chances and risks associated with such systems, which can play an important part in achieving our ambiguous climate targets.