At the end of September, we participated in a three-day study tour in Tuscany as part of the GreetGeo project, aimed at exploring the region’s best practices in geothermal energy utilization—from deep geothermal power plants to shallow heat pump systems. The program offered insights into how technological innovation and energy efficiency can go hand in hand, and how environmentally friendly technologies support sustainable business models.
The GreetGeo project promotes research and the use of geothermal energy as part of the green transition, connecting key stakeholders to develop sustainable energy solutions that support SMEs. The second on-site meeting, organized by COSVIG, focused on the progress of the four main work packages (WP1–WP4) and the planning of future tasks, including stakeholder engagement, database development, and the exchange of regional best practices. Each partner presented examples and opportunities from their own regions, covering both deep and shallow geothermal applications.
The birthplace of geothermal energy: Larderello
The first day began at the Geothermal Energy Museum in Larderello, known as the cradle of geothermal power. Within the historic Palazzo de Larderel, interactive exhibits showcased the journey from Etruscan hot springs and the first electricity generation experiment in 1904 to the modern power plants that today supply about one-third of Tuscany’s electricity needs.
We also visited an educational well drilled in 1956, which produces ten tons of 180°C steam per hour—a vivid demonstration of the power lying beneath our feet. The story of François Jacques de Larderel, who established the first boric acid extraction plant here in 1818, illustrated how this pioneering region became a global geothermal hub.
Today, 34 power plants in Tuscany produce around 6,000 GWh annually with a total capacity of 916 MWe, meeting over 30% of regional electricity demand. 21 district heating systems provide 148 MWt of thermal capacity to more than 5,000 users. Geothermal heat is also used directly in dairies, breweries, greenhouses, and meat processing plants, while pilot projects explore Spirulina microalgae cultivation and CO₂ reuse. Operated by Enel Green Power, this system includes 500 wells and 700 km of pipelines, making it the oldest and most innovative geothermal network in the world.
Geothermal energy also plays a major socio-economic role: about 1,800 people are directly or indirectly employed in the sector in Tuscany, and 3,500 nationwide. Out of ten municipalities with geothermal plants, nine already have district heating systems, while the rest are under construction. Geothermal heat provides affordable home heating and supports SME growth in the agri-food, service, mechanical, and chemical industries.
A particularly inspiring example of circular cooperation is the partnership with Nippon Gases Operations, which recycles naturally occurring geothermal CO₂ into liquid form for food industry use. This innovative project could supply up to 30% of Italy’s total food-grade CO₂ demand, setting a precedent for sustainable resource use and industrial synergy.
In the afternoon, we visited local businesses using geothermal energy, including Vapori di Birra in Sasso Pisano—the first Italian brewery powered by geothermal steam. Its custom-designed equipment enables maximum energy efficiency and minimal environmental impact.
Another highlight was the Formaggerie Toscane dairy where geothermal heat is used to operate both the heating and cooling systems, increasing sustainability and reducing energy costs. The geothermal energy is sufficient to cover the plant’s entire annual energy demand, with electricity used only during maintenance periods. The geothermal energy comes from an Enel Green Power plant, delivered via a 350-meter pipeline that transports 135°C heated steam directly to the factory. Unlike conventional vapor-compression cooling systems, this setup produces cold air using geothermal heat. The system is expected to achieve annual electricity savings of 45,000 kWh, reduce CO₂ emissions by 12,000 kg per year, and cut cooling system operating costs by at least 50%.
Nature meets energy: Le Biancane Natural Park
Our next stop, the Le Biancane Natural Park, vividly showcased geothermal phenomena: steaming vents, bubbling mud pools, and colorful mineral landscapes. Thanks to its unique geology and climate, the area hosts rare vegetation and an almost otherworldly atmosphere. Together with Enel Green Power, the municipality created an educational trail through this geothermal wonderland, including historical industrial sites where boric acid was extracted as early as the 19th century.
Shallow geothermal in Florence
The third day focused on low-enthalpy geothermal systems used in historic buildings. We visited installations at the Museo dell’Opera del Duomo and Museo di Santa Croce, where geothermal heat pumps are being integrated for heating and cooling. The open-loop system extracts groundwater, uses it in a separate circuit for heat exchange, and reinjects it into the same aquifer unchanged.
We also learned about the “Green Island” research project on Pantelleria, a small volcanic island near Sicily, developed in collaboration with Idrogeo Services (Alessandro Murratzu) and Geologia & Ambiente (Marco Mazzalon). This pilot applies a closed-loop geothermal system based on underground heat exchangers. The technology requires no special geological conditions, has minimal surface impact, and emits no pollutants, circulating water within a sealed underground network that functions like a deep radiator.
The study tour concluded with site visits to Palazzo Compagni and Santa Croce, where participants could observe how geothermal heating and cooling technologies are integrated into the restoration and energy efficiency of heritage buildings—demonstrating how innovation and tradition can work hand in hand for a sustainable future.
The GREETGeo project is funded by the European Innovation Council and SMEs Executive Agency (EISMEA) under the Interregional Innovation Investments (I3) Instrument.
