High Quality Content by WIKIPEDIA articles! The energy sector in Mexico has certain limitations in terms of private participation and foreign companies are allowed to operate in the country only through specific service contracts. As required by the Constitution, the electricity sector is federally owned, with the Federal Electricity Commission essentially controlling the whole sector. Attempts to reform the sector have traditionally faced strong political and social resistance in Mexico, where subsidies for residential consumers absorb substantial fiscal resources. The electricity sector in Mexico relies heavily on thermal sources, followed by hydropower generation. Although exploitation of solar, wind, and biomass resources has a large potential, geothermal energy is the only renewable source with a significant contribution to the energy mix. Expansion plans for the period 2006-2015 estimate the addition of some 14.8 GW of new generation capacity by the public sector, with a predominance of combined cycles.