Although Spain's mountainous terrain would appear to be wellsuited to hydroelectric power production, the scarcity of water limited such potential and was the principal reason for Spain's heavy dependence on thermal power. In 1986 only 27.2 percent of the country's electricity came from hydroelectric plants, while 50.6 percent came from conventional thermal plants, and 22.2 percent came from nuclear plants. The most important fuel for the production of electricity was coal, which generated about 40 percent of the total. In 1987 the production of electricity amounted to 132,000 million kilowatt hours--about six times the amount produced in 1960 and twice the production level of 1970. The total installed capacity of the predominantly privately owned electrical system was about 40 gigawatts--an amount large enough to meet the country's needs and to allow some exports. In the second half of the 1980s, the growth of the demand for electrical power was less than anticipated, and Spain had a supply adequate to last until the mid-1990s. The Spanish level of per capita electrical power consumption was among the lowest in Western Europe, surpassing only those of Greece and Portugal.

A key element in the future of Spain's electrical power industry was the role to be assigned to nuclear power. Nuclear power was an important factor because of scarce petroleum reserves, the limited potential for hydroelectric power production, and the presence of significant uranium deposits. The first PEN, drawn up in 1978, emphasized the role that nuclear power would play in meeting the nation's ever-increasing need for electricity. The revised PEN of 1984 postponed the opening of the Lemoniz Nuclear Power Plant for political reasons, and it continued the mothballing of three other nuclear plants. The government decided, nonetheless, that if the demand for electricity increased by more than 3 percent, work on one of the plants might be restarted. The new PEN also emphasized the benefits of increased natural gas consumption.

Data as of December 1988