The Devil’s Valley

Monday, 16th November 2009 by

Using the heat from the Earth's interior to generate electricity is known as the creation of geothermal power, and in the examples featuring 2000-metre boreholes, it's correctly believed to be a fairly recent development. In some places however, the energy from the hot parts of the Earth's inner layers can be harvested with little more than a spade.

The area around Larderello1 in Tuscany's Cecina valley has an abundance of hot wells (lagoni) and natural steam fountains (sofioni), where the escaping steam leaves the ground under very high pressure at temperatures of over 200°C; making it ideal for power generation.

The gases released here also smell strongly of sulphur, which is why this is known as Valle del Diavolo – "The Devil's Valley".

Larderello, Tuscany, Italy

A working geothermal generator (using a steam-powered piston engine) was demonstrated2 here as early as 1904, and Larderello actually became the location of the world's first geothermal power plant all the way back in 1913! Today, over one third of the electricity consumed in Tuscany is produced by local geothermal plants.

The whole countryside around the town is criss-crossed by large insulated pipelines transporting superheated steam from the wells to the power station.

In 2005, nearly 10% of the world's geothermal electricity was produced in Larderello, but as more, high-tech geothermal power stations have been built around the world, this proportion has shrunk dramatically.

You can take a guided tour if you're in the area, of which one of the highlights is a steam outlet that the tour guide opens with a remote control to create a deafeningly loud, and very impressive-looking column of steam:

You can read more about Geothermal power at Wikipedia.

  1. A town founded by a Frenchman who pioneered geothermal engineering, François Jacques de Larderel (1790-1858). Today, the entire town is owned by Enel, Italy's largest power company. ↩︎

  2. It successfully lit four light bulbs. ↩︎