In the canton of Geneva, the per capita electricity consumption of private households increased by 12.1% between 2000 and 2010. The electricity efficiency program ECO21 conducted by the Services Industriels de Genève (SIG) was initiated with the goal of reducing the demand. A territorial characterization of electricity demand permits designing such programs and making ex-ante estimations of savings potentials. To extend this approach to the whole Swiss territory, a collaboration was initiated with SIG to develop the ElectroWhat platform that decomposes the yearly electricity consumption of every Swiss municipality into estimated load curves per activity and per electric appliance.