Can geothermal startups help Europe achieve independence in clean energy through drilling?

      In the forested hills south of Munich, Germany, engineers are boring 8 km into the ground in an effort to extract endless clean energy from the Earth's molten, radioactive center. This initiative could provide a model for affordable geothermal energy extraction, assisting Europe in powering cities, heating homes, and decreasing its dependence on fossil fuels.

      The drilling operation is run by Canadian company Eavor, part of a new wave of startups aiming to establish geothermal energy as a significant player in the energy sector. Equipped with a range of plasma pulse drills, steel shot cannons, and robotic worms, they intend to harness Earth's heat from nearly any location.

      Traditional geothermal plants depend on rare underground reservoirs of superheated water, like those found in Iceland and parts of Italy. In contrast, Eavor’s system necessitates only hot rocks, a sealed loop of piping, and some innovative thermodynamic principles. However, achieving significant depth is crucial for its success.

      "Our system functions like a radiator, but rather than radiating heat, it draws it from superheated rocks," explains Robert Winsloe, Eavor's executive vice president, to TNW. "By drilling deep enough, we can extract heat from virtually any spot without needing underground aquifers."

      Eavor's geothermal project in Geretsried, Germany, aims to substitute natural gas with clean heat for the Bavarian town of approximately 25,000 residents.

      To assemble its underground heat generator, Eavor drills straight down 4,500 meters, enough to access rocks heated to 160°C, then extends horizontally for an additional 3,000 to 3,500 meters before returning upward through a secondary vertical well. The outcome is a vast, closed-loop circuit isolated from the surrounding Earth.

      Water circulates continuously within the loop. As it descends, it absorbs heat from the hot rock below. This heated water then ascends spontaneously while cooler water from above moves downward to replace it. This natural circulation, known as a thermosiphon, enables movement without pumps, enhancing the system's energy efficiency.

      At the surface, the hot water passes through a heat exchanger, which transfers its heat without mixing with the water. Within the exchanger, the geothermal water’s heat is transmitted to a separate water network linked to the district heating system. During summer months, when heating requirements wane, some underground heat is redirected to a steam turbine to generate electricity.

      The €370 million project began drilling in July 2023 and has already secured substantial backing: €91.6 million from the EU’s Innovation Fund and a €45 million loan from the European Investment Bank. Eavor plans to commence power generation at the site by the end of 2025.

      “All eyes are on Geretsried,” states Sanjeev Kumar, head of policy at the European Geothermal Energy Council. “If successful, it could significantly advance geothermal energy.”

      Europe has historically been a leader in harnessing underground heat. The Romans exploited geothermal energy over 2,000 years ago to heat royal villas. The world’s first industrial geothermal power plant began operations in Larderello, Italy, in 1911, and by the 1930s, Iceland utilized its volcanic hot springs for widespread energy supply.

      However, geothermal energy currently accounts for only 0.2% of Europe’s electricity and 0.7% of its heating, a small fraction compared to wind and solar energy. Geothermal offers a unique advantage that renewables cannot: reliable, baseload power that stabilizes the grid when solar or wind energy is unavailable. Moreover, geothermal plants occupy significantly less land than equivalent solar or wind farms. Furthermore, it can provide both heat and electricity, making it an effective alternative to natural gas, a point recognized by many European politicians.

      "Russia’s invasion of Ukraine has altered everything," remarks Kumar. “Europe is now increasingly investing in geothermal energy as it seeks independent, clean energy sources.”

      The International Energy Agency estimates that geothermal energy has the potential to meet the world's electricity demands 150 times over. However, it remains costly and geographically constrained at present. Traditional geothermal systems can only access areas where hot water rises near the surface, and there are concerns about the risk of earthquakes associated with underground drilling.

      Eavor aims to change this dynamic and unlock geothermal's potential, with numerous startups also working toward making geothermal energy more affordable and safer. Many of these companies are focused on developing faster, more efficient drilling technologies to improve the economic viability of geothermal energy.

      One such company, Slovakia’s GA Drilling, has developed a rig that combines a conventional diamond-tipped drill with an electrical device that emits ultra-hot “plasma pulses” to break hard rock.

      “The key to scaling geothermal is reducing drilling costs,” states Matus Gajdos, the company’s head of product, asserting that the plasma pulse drill could work at double the speed of standard tools, based on geological conditions. This advancement could enhance the feasibility of harnessing Earth’s heat.

      GA Drilling aims to