Billowing white steam, boiling waters and a landscape that resembles the surface of the moon: this is Larderello, a geologically active area in the Pomarance district in southern Tuscany renowned for its geothermal productivity. It has been known since ancient times for its volcanic nature and exceptional hot springs.
The Romans used its sulphur springs for bathing. During the 18th and 19th century, they were exploited to extract boric acid. The region was the site of a pioneering experiment in geothermal energy production in 1904, when five light bulbs were lit by electricity produced through steam emerging from vents in the ground - the first ever practical demonstration of geothermal power. In 1911, the world's first geothermal power plant was built in the Valle del Diavolo ("Devil's Valley"), named for the boiling water that rises there.
Its geology makes it uniquely conducive to geothermal power production, with hot granite rocks lying unusually close to the surface, producing steam as hot as 220C (396F). However, in recent years, concerns have been expressed about the sustainability of its steam supply, as a 30% drop in steam pressure levels has been recorded from the maximum levels of the 1950's.
The region is known as “Devil's Valley” for its occasional volcanic eruptions, caused by explosive outbursts of steam trapped below the surface. The largest volcanic crater is the Lago Vecchienna crater, now filled by a lake, which last erupted around 1282.
Visitors can visit the Larderello Geothermal Museum, founded by Larderello Spa in the late 1950s. The museum includes the history of geothermal energy, from research to drilling, to the various systems for using geothermal fluid for the generation of electricity, thermal power and mechanical power. Original models and equipment also depict the history of drilling.