published on 18 November 2016 in earth

Brief history of geothermal energy

It accounts for 25% of the energy needs of Tuscany, 1.3% of national demand and it is estimated that in 2050 it could meet 3% of the electricity demand of the entire planet. And yet we can say that currently geothermal energy is the Cinderella of renewables, at least in terms of notoriety. Confirming this is a Eurobarometer Report (a survey of the European Commission on social and scientific-technological issues), according to which, in Italy, only 25% of people have a clear understanding of geothermal energy. A veritable flop if one thinks that Italy, as well as having exceptionally suitable geophysical characteristics for the cultivation of this resource, such as the presence of volcanic areas and hydrothermal vents, is also the cradle of geothermal energy.

Travertines Pamukkale

Pamukkale thermal springs, Turkey

But let’s go to the roots of the relationship between man and geothermal energy, a story that has lasted for thousands of years.

Although this resource is increasingly gaining space in the energy horizon of the future, we must not forget that this is one of the first energy resources with which man interacted in the past.
According to a study published by the University of the United Nations, in fact, the history between geothermal energy and Homo sapiens could even date back as far as 14,000 BC, even though the first archaeological finds that testify to this relationship date back to between 9 and 5 thousand years.
According to archaeologists, the first men used to settle in the vicinity of areas active from the geothermal point of view, not only to enjoy the benefits of the thermal waters, but also for cooking and the use of volcanic products. These first man-geothermal relationships, according to experts, already took place 13,000 years ago on a Japanese island and 7,000 years ago on the Asian continent. While on the Greek islands there is no lack of traces of therapeutic and cosmetic uses and in the Middle East the signs of a connection with rituals and religious beliefs.

The Great Geyser. Strokkur. Iceland.

The Etruscans and Romans
According to some scholars, the real “fathers of the geothermal industry” were the Etruscans. A people that not only used to build most of its settlements and cities at hydrothermal vents, but which even made geothermal energy products – such as alabaster, travertine, iron oxides and mud baths – veritable bartering goods. Pioneers not only in trade but also in crafts, the Etruscans were the first to coat their tools with enamel, using borax, a boron compound available in boraciferous sources, which at high temperature is transformed into an insulating glass and is still used for welds.
The technologies developed by this people were absorbed and perfected by the Romans, for whom every aspect of daily life was interwoven with spas: those used for religious purposes, for socialising, relaxation and treatment or in political life. And from Agrippa onwards, many powerful men tried to win popular support by building more and more sumptuous as well as affordable spas. At spas the Romans looked after themselves, heard musical performances, kept themselves informed and concluded business.
But then, as the Latins said: Balnea, vina, Venus corrumpunt corpora nostra; sed vitam faciunt (spas, wine and love corrupt our bodies, but they make life good).


Pietro Ginori Conti, the first geothermal plants in Larderello (Source: Italian Geothermal Union)

Geothermal power plants
Let us now take a journey through time, remaining, however, in Italy, a country that can rightly be called “geothermal,” not only due to the geological characteristics of the territory, but also because it was right here that the first geothermal power plant in the world was built.
It was in 1800, the century in which, thanks to the rapid development of thermodynamics, the discipline that studies the transformations of work into heat and vice versa, that scientists learned to convert steam into mechanical energy with increasing efficiency and thus into electricity with the aid of turbines and generators. The step towards geothermal energy was really within reach and was not long in coming.
Rich in hydrothermal vents, home to the borax industry and frequented by men of science, Larderello, in Tuscany, had in its DNA all the credentials to host the first geothermal power plant. For the production of boric acid, in fact, a lot of energy was required, historically obtained by burning wood collected from forests in the area. But what if instead of trees geothermal energy was used?
Armed with this insight, in 1827, Francesco De Larderei, founder of the borax industry, built the first geothermal energy plant. From this date onwards there were a succession of very important milestones in the history of geothermal energy: in 1904, Pietro Ginori Conti lit the first five light bulbs powered by geothermal energy and only 9 years later, in 1913, the first real geothermal power plant opened up a new era.

After a forced break during the Second World War, the Italian geothermal industry has slowly but steadily grown, reaching an installed capacity of approx. 1 GW. A number which puts Italy in sixth place in the ranking of the world’s “most geothermal countries”.
With low emissions and available 24/7, geothermal technology is today considered by many scientists as a potential leader in the transition to a carbon-free society. It is no coincidence that, just one year ago, the COP21 in Paris saw the birth of the Global Geothermal Alliance, a coalition of 38 countries that have joined together with the aim of strengthening the role of geothermal energy in the international arena.
Be careful, though, because like any technology, also geothermal energy has its impacts on the local area and on the lives of those who live there. These include disturbance to the landscape, flora and fauna, physical effects (such as induced seismicity and subsidence), noise, thermal pollution (e.g. due to vapour release) and chemical pollution (such as gaseous emissions into the atmosphere). Most of these effects can be minimised through mitigation and monitoring technologies, but it is nevertheless worth remembering that, if we do not want to jeopardise the historical relationship between man and geothermal energy, local people must be involved in the innovation process from the very first steps .

Map of installed geothermal capacity, source Bertani (2015)

Map of installed geothermal capacity, source Bertani (2015)

By Anna Pellizzone

Sources and insights

  • Bertani, R.: Geothermal Power Generation in the World 2010-2014 Update Report. Proceedings World Geothermal Congress 2015 Melbourne, Australia, 19-25 April 2015
  • Geothermal energy in human history, culture, and practices – Selected highlights, The United Nations University, 2003 http://www.os.is/gogn/flytja/JHS-Skjol/UNU%20Visiting%20Lecturers/Beata01.pdf
  • International Renewable Agency, http:// www.irena.org
  • the Fumaroles of Larderello, http://www.siena-agriturismo.it/soffioni_di_larderello.html
  • VIGOR, Applicazioni Geotermiche per uno Sviluppo Sostenibile, Produzione di Calore ed Energia Elettrica, Abate et al., 2014, Published by CNR. IGG, Pisa Research Area
  • Rischi ambientali connessi all’utilizzo della risorsa geotermica: cause e buone pratiche per la loro minimizzazione, Giamberini et al., 2016, Published by CNR. IGG, Pisa Research Area
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