Historically, Switzerland's longest-serving and most important source of renewable energy has been hydropower. But the "new" renewables including solar, wood, biomass, wind, geothermal and ambient heat also play an increasingly important role in today's Swiss energy mix. The long-term potentials of domestic renewable energy indicate that, for all forms, the prospects for electricity and heat are very sound. However, it is also clear that, primarily for economic reasons, it will only be possible to fully utilise the major potentials of photovoltaics or geothermal energy in approximately 30 years time. Other renewables such as wood and biomass, ambient heat, electricity from small-scale hydropower plants and, to a modest extent, wind, are available now and in some cases are also already economically attractive.