Italian princes aren’t a regular sight in the history books of renewable energy, but at the turn of the last century, on a Tuscan hillside, Piero Ginori Conti, Prince of Trevignano, set about harnessing natural geysers to generate electricity.

In 1904 he had become head of a boric acid extraction firm founded by his wife’s great-grandfather. His plan for the business included improving the quality of products, increasing production and lowering prices. But to do this he needed a steady stream of cheap electricity.

In 1905 he harnessed the dry steam (which lacks moisture, preventing corrosion of turbine blades) from the geographically active area near Larderello in Southern Tuscany to drive a turbine and power five light bulbs. Encouraged by this, Conti expanded the operation into a prototype power plant capable of powering Larderello’s main industrial plants and residential buildings.

It evolved into the world’s first commercial geothermal power plant in 1913, supplying 250 kW of electricity to villages around the region. By the end of 1943 there was 132 megawatts (MW) of installed capacity in the area, but as the main source of electricity for central Italy’s entire rail network it was bombed heavily in World War Two.

Following reconstruction and expansion the region has grown to reach current capacity of more than 800 MW. Globally, there is now more than 83 GW of installed geothermal capacity.