In Ostellato the site with 240 MW of capacity capable of heating 120 thousand homes
Another 15 interventions in pipeline, the next will start in the Milan area in 2024
Ilaria Vesentini

The first well branded Fri-El Geo is already under construction in Ostellato, between Ferrara and the sea. It will take two years to complete what will become Italy’s first medium-enthalpy geothermal plant, capable of generating 240 MW of thermal energy-just enough to heat 120 thousand homes-and 30 MW of electricity on just one and a half hectares of land. “It will be the first of 15 other plants we have in the pipeline within our ambitious ‘Pangea Project.’ The next one will start in the Milan area in 2024. But there are at least 100 suitable sites we have identified in the Po Valley, where with geothermal technology we could eliminate 50 percent of domestic boilers, reduce national gas consumption by 15 percent (10 billion cubic meters less), and eliminate more than 17 million tons of CO2 from the polluted air of northern Italy.” This is how Ernst Gostner, co-founder with his brothers Thomas and Josef of the Bolzano-based Fri-El Green Power group (among Italy’s leading producers of renewable energy from wind, biomass, and biogas, €623 million in 2022 sales and €286 million in Ebitda) and president of the newco Fri-El Geo, explains the untapped potential of geothermal energy as an alternative for the green transition.

A clean source with zero emissions and very low land consumption, geothermal energy has so far been underestimated in our country, relegated to the thermal anomaly areas of Tuscany where the earth is very hot and where Enel Green Power uses high-enthalpy “flash” technologies, with 180-degree vapors to move the turbines. “In contrast, medium-enthalpy geothermal is universal and zero-risk because it works at 150°C and 18 bars of pressure,” says Gostner, who has been funding studies on the subject for two years, driven by the need to find an economical solution with which to heat the 30 hectares of hydroponic agricultural greenhouses built in Ostellato by another group subsidiary, Fri-El Green House. The thermal gradient of 2-3°C for every 100 meters of descent underground is exploited to reach 150 degrees of temperature around 5-6 km depth. It is worked with a withdrawal well and a re-entry well (about 30 cm wide), the hot fluid is extracted from the former and then 100% re-injected into the latter (no emission and no danger of subsidence). The subsurface works as a radiator, while on the surface heat exchange takes place: it heats both water to be sent to the district heating network (with a very high efficiency compared to photovoltaics, which requires at least two hectares for 1 MW of power, while in geothermal with 2 hectares it reaches 320 MW), and an organic oil (a hydrocarbon) that evaporates at 70°C with which to move a turbine to produce electricity (with a low efficiency, 13%).

“In the Po Valley we know where the formations or carbonate layers containing geothermal fluid are because of the thousands of surveys done to extract oil&gas. We have identified the 15 best sites and we start from there, that is our competitive advantage,” explains Gostner, who has already invested 50 million euros in the development of the first plant in Ostellato, but will need 240 million euros in all to complete it, including 140 million euros to drill eight wells (4 doubles), 60 million for the surface energy exchanger-production system and another 20 million for connection works to power and district heating networks. “In Germany geothermal is growing by 300% per year, the Netherlands is turning 70% of its 2,600 hectares of greenhouses and 100% of homes to geothermal heating. For a few months now, even the Italian government has been listening to us and a small earthquake has started: all the big names in the sector have sought us out, Enel, A2A, Iren,” the president concludes, “Sace has included us among the best projects for green energy and will guarantee coverage of 80% of the plant costs, and even CDP will finance us. And every week at least one or two mayors call us to switch to geothermal.”

PROSPECTS
“There are 100 suitable sites in the Po Valley where geothermal energy could eliminate 50% of domestic boilers”.

IN OTHER COUNTRIES
“In Germany, technology is growing by 300 per cent per year, in the Netherlands 100 per cent of homes are being transformed.”

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The Sun 24 Hours – Wednesday, March 29, 2023 – No.87