In 1969 French engineers brought their country's first geothermal heating plant on stream, providing heat and hot water for 2,000 homes. Today, only Iceland, where some 150,000 dwellings get their heat from beneath the earth's surface, boasts more geothermally heated homes than does France. And France has only begun its geothermal development.
Recently, the French government, which prides itself on having the most ambitious program in renewable energy sources after that of the United States, announced that the administering agency's budget for the program will be boosted from 140 million francs this year to 210 million francs (about $51 million) in 1981.
Announcing the increase, Industry Minister Andre Giraud said he expects renewable sources to be furnishing about 5 percent of France's energy needs by 1990 -- i.e., 10 million to 12 million tons of oil equivalent (MTOE). They now supply about 1 percent.
Of these sources -- solar, biomass, wind, waves, tides, and geothermal -- the latter (geothermal energy) will produce about 1 MTOE per year, Mr. Giraud said. Between 7.5 and 9 MTOE will come from biomass.
The government wants some 500,000 houses heated by geothermal means by 1990. However, strong advocates of this unique source of power including Jacques Varet , who heads the geothermal department of the government's Bureau de Recherches Geologiques et Minieres (BRGM), emphasize that the potential for generating heat -- and even electricity -- from geothermal sources in France is enormous.
Mr. Varet says that about two-thirds of France's territory is suitable for geothermal exploitation; i.e., it has sufficient deposits of "low-grade" geothermal energy, containing water up to 70 degrees C. for heating. Much hotter water is needed to produce electricity, and France has some but not much of that.
Fcould easily supply 10-13 MTOE per year, compared with the one MTOE targeted by the government for 1990. About one-third of the energy consumed in France (i.e., about 60 of the 180 MTOE per year) is used for low-temperature heating -- mainly hot water and heat for private dwellings and small industries.
Currently, there are six geothermal plants operating in France -- four near Paris and two in the southwest part of the country. Three new facilities should be completed by the end of this year, and about a dozen more have reached the advanced experimental stage. BRGM expects to be developing about 20 sites suitable for geothermal exploitation per year by the end of the century.
A typical plant, according to BRGM officials, including the drilling of two holes (one to extract the water, one to return it, heavily polluted, to the earth) some 1,500 meters deep, costs about $3.5 million. It pays for itself in about eight years and lasts at least 30 years. The newest geothermal plant in France -- at St. Denis-en-Val -- will soon provide energy worth 3,000 to 5,000 tons of oil equivalent per year, BRGM experts claim.
But no matter how ambitious France's renewable sources program may be, it is not without critics. Environmentalists have always argued that even more money should be spent on nonnuclear sources. Recently, however, the quasi-Establishment Socialist Party added its voice to the growing chorus of critics, pointing out that the newly boosted budget for the Commissariat a l'energie solaire (COMES), which administers the renewable sources R&D program, including geothermal energy, is only 1 percent of the total sum spent on the construction of nuclear power plants in France last year.
To sell their case, rather than rely exclusively on appeals to nationalistic feelings about energy self-sufficiency, they have begun to talk commercial advantage.
Mr. Varet of BRGM, while never denying that geothermal energy could make a significant contribution to France's overall energy picture if given the proper chance, says that France should consider exporting the geothermal technology it has acquired in the past decade. He says that knowledge and equipment used in France's own experience in geothermal energy could be exported to developed countries mainly for low-temperature home heating. It could also be sold to developing countries in Latin America, Indonesia, the Philippines, East Africa, some Mediterranean regions, and South Asia, where it would be used mainly for the production of electricity.