Switzerland is heavily dependent on imported petroleum, which supplied 50% of the primary energy consumed in 1995. Between 1970 and 1995, the share of natural gas in primary energy consumption rose from 1.3% to 8.5%. Switzerland's electric power plants had an installed capacity of 15,657 million kW in 2001, of which hydroelectric plants accounted for about three-quarters. Electricity production totaled 62,700 million kWh, of which 4% was from fossil fuels, 56.8% from hydropower, 36.9% from nuclear power, and 2.3% from renewable sources. In 1996 there were five nuclear plants in operation. In 1988, the government suspended plans to build a sixth reactor at Kaiseraugst (near Basel) because of pressure from environmentalists. Two other nuclear facilities, which were in the early stages of planning, are not likely to be built in the near future. The only natural gas produced in Switzerland comes from the Finsterwald Field, in the Lucerne canton. Natural gas consumption, which totaled 2.2 billion cu m in 1995, came mostly from the Netherlands, the Norwegian sections of the North Sea, and the former USSR. Switzerland discourages the burning of coal and other hydrocarbons.