 The Three Mile Island accident (United States) prompted the Swedish parliament in 1980 after a referendum to decide that no further nuclear power plants should be built and that a nuclear power phase-out should be completed by 2010. , the use of renewables amounted to 26% of the energy supply in Sweden, most important being hydropower and biomass.In 2003, electricity from hydropower accounted for 53 TWh and 40% of the country's production of electricity with nuclear power delivering 65 TWh (49%).At the same time, the use of biofuels, peat etc.