Investigations on a novel gravitational energy storage system using a high-cycle accumulation model

One of the main concerns of our days is moving away from fossil fuels and implementing renewable energy sources into the energy supply. Large-scale energy storage is one of the biggest obstacles to the energy system’s change. The required energy storage systems are not yet available. This paper presents a novel concept for gravitational energy storage. The energy storage is realised in the form of potential energy in the subsurface by injecting a pressurised fluid into a previously generated cavity. High pressures can be achieved in the inflatable cavity, allowing a large amount of energy to be stored. Numerical calculations of a deep cavity are presented. The boundary condition of the charging and discharging of the cavity are realised in the FEM simulation using a fluid link. The explicit high-cycle accumulation model is applied, whereby both the soil behaviour and the energy storage capacity can be evaluated. The preliminary results are promising in the aspect of energy efficiency and storage capacity of the proposed system.