Burning fossil fuels for heat is bad for the planet. So we need to change how we heat our homes and businesses. We have all the tools and technologies to meet the heating challenge of the 21st century. The heating challenge is one of coordinating change at speed. It is a challenge of scaling up. We need to work together to get the heat decarbonisation boulder rolling. Thermal storage is one part of the technology mix that will help decarbonise heating in an increasingly renewable electricity grid.