Sensible heat storage is based on heating a material without changing its phase. The material is heated up by heat transfer. Its storage capacity is determined by the material's specific heat capacity, the temperature difference between charging and discharging, and the volume or. Thermal storage technologies have the potential to provide large capacity, long-duration storage to enable high penetrations of intermittent renewable energy, flexible energy generation for conventional baseload sources, and seasonal energy needs. Most commonly this method is used to store excess thermal energy for later recovery as thermal energy for space heating or the production of hot water for domestic use, but larger scale facilities are also possible.