The volcanic region of Reykjanes Peninsula, Iceland, has many natural hot springs. The Blue Lagoon is an artificial lake fed by the surplus water drawn from the geothermic power station at Svartsengi. The colour of the lagoon results from the mineral mixture of silica and chalk from the basin combined with the presence of decomposing algae. Rich in mineral salts and organic matter, the hot waters, approximately 40°C, (104°F) of the Blue Lagoon are known for their curative properties, particularly for skin ailments. The use of geothermic energy, a renewable, clean, and inexpensive energy source, is relatively recent, but it is being used with growing frequency. In Iceland, in 1960 less than 25 percent of the population benefited from this source of heat, whereas today it meets the needs of 85 percent of Icelanders. By using geothermic energy to produce hydrogen fuel cells, Iceland plans to make its economy oil-free by 2040.