Converting renewable electricity into heat and then storing this heat can be a good way to use excess solar and wind power and reduce the use of natural gas. This emerged from the study Power to heat en warmteopslag in warmtenetten (Power-to-heat and thermal storage in heat networks), which CE Delft carried out on behalf of the Netherlands Enterprise Agency. This study provided insight into the possibilities for using power-to-heat and thermal storage to make heat networks more sustainable. For power-to-heat two technologies were investigated: heat pumps and electric water heaters. For thermal energy storage (TES), we look at tank storage (TTES), storage in an isolated pit in the ground (PTES) and high-temperature storage in an underground aquifer (HT-ATES).