The Greek etymology of the term says it all: geō, Earth, and thermós, heat. The heat coming from deep within Earth’s crust transforms water in steam, which has accompanied mankind along its evolution to serve many different purposes: to heat, to cook, to power spas. In the eighteenth century, men pioneered the first industrial uses of geothermal energy and by the start of the nineteenth century, it opened the door for electricity.
Right until the sixties, the world’s hotspot of geothermal energy was the small Tuscan hamlet of Larderello, which held the world record for installed capacity until the eighties, when this kind of energy sources went global on a large scale. In the last decade, countries like the United States and Iceland made the most of their own large geothermal resources, exploiting steam for household heating purposes. Suffice to say that 95% of Icelandic households are heated thanks to steam collected straight from the earth’s crust.
According to data from the 2019 IRENA report, geothermal energy’s contribution to the global renewable capacity amounts to 13 GW. Geothermal energy is less spread out than other renewable sources since not all territories hold large pockets of trapped heat in their subsoil. Fortunately, these constraints don’t hamper the development of its potential. Following the 2015 COP21 (Conference of Parties) conference in Paris, the Global Geothermal Alliance was established with the UN’s blessing to fast-track this renewable resource in a quest to hasten the energy transition process.