Electricity sector Evolution of electricity production in TWh in Spain (1980-2005) Thermal power stations – nuclear fuel hydro renewable fossil See also: Electricity in Spain Electricity in Spain covers the elements of power system mainly in its generation sources and other general developments. The average electrical energy generated in Spain has evolved in recent years from 56 of the energy generated by fossil fuel power plants (mainly coal and fuel oil) in 2000 to an increase in renewable energy (which in 2009 covered 26 of demand), and the creation of numerous combined cycle plants, which this year covered 29 of demand, becoming the main source of electricity generation.For its part, the production of hydropower varies with age (depending on rainfall), and coverage of demand by the rest of renewables is in progress, encouraged by successive governments. Thus, while wind power in Spain in 2005 covered 7.7 of demand in 2009 reached 13 . On the other hand, the six Spanish nuclear power plants have seen their participation in the coverage of demand gradually diminished due to this steady growth in recent decades and its stabilization due to the nuclear moratorium, from 35 in 1996 to less than 20 in 2009. The global system of transport conduits of Spain operates with voltages above 220 kV (typically 500 kV). The household electricity is 230 V nominal, with a frequency of 50 Hz and plugs are C: European plug, and IRAM 2073 plug (grounded) as defined by the European electrotechnical standards.