But thats the problem they are looking to solve… there are quite a couple of cold months in Finland and I think a large portion of their heating is electric/distict anyway so they might as well store heat rather than energy. This probably serves as a rather good balancing mechanism to the grid actually, and I could definitely see this be a thing I northern Sweden for instance , where electricity is basically free during the night and when it is windy it’s actually kind of a problem to get rid of it all.