Geothermal energy has huge potential in the energy sector and is a factor to consider in the green energy transition. Its direct use worldwide has slowly but steadily been rising from around 9,5 Megawatts in 2009 to over 16 Megawatts in 2023 (Statista, ThinkGeoEnergy), with the top producers and users worldwide being U.S., Indonesia and the Philippines. Not surprisingly, also, in the Scandinavian countries, geothermal energy has been effectively exploited for decades. We tracked down Aivar Auväärt, the head of the geothermal energy department at the Geological Survey of Estonia and asked him 5 questions about geothermal energy and its development in Estonia.
1. Why is geothermal energy important in the world and for Estonia?
"Geothermal energy is a form of renewable energy that uses the heat in the Earth’s crust. Its use reduces carbon dioxide emissions and helps to reduce environmental impact. This is an important step in mitigating climate change and ensuring sustainable development.
Exploiting geothermal energy from Estonia’s subsurface helps us reduce dependence on imported energy from other countries, especially when it comes to fossil fuels. Since geothermal heat is a local resource, it helps us to improve our energy independence and reduce the risk of interruptions and severe price fluctuations in the energy supply.
The thermal energy of the earth's crust is a stable and permanent source of heat because the earth's surface maintains a stable temperature throughout the year, and geothermal heat pumps can provide a stable and reliable heat supply without major fluctuations."
2. What is the importance and potential of geothermal energy compared to other green energies?
"Geothermal energy is more stable and is not dependent on sunlight like solar energy. Solar energy production depends on weather conditions and the intensity of sunlight, while thermal energy is constantly available. Unlike wind energy, thermal energy is available even on calm days with no wind. Wind energy production depends on wind speed, which can be variable and unstable. Compared to hydropower, thermal energy from the earth's crust is also available in areas with no water body, which is necessary for hydropower production. Compared to biomass and biogas, thermal energy from the earth's crust is a clean energy source, not involving combustion processes or creating air pollution."
3. What is the status of geothermal energy adoption in Estonia now?
"In Estonia, the use of thermal energy is a growing trend. Although, it is difficult to find accurate statistical data on current use. The Estonian Nature Information System currently describes more than 1,000 heat systems, for which more than 4,000 boreholes have been drilled to date."
4. What is currently happening in EGT regarding geothermal energy?
"In August 2021, Estonia began researching
the potential of geothermal energy (see details:
https://t.ly/uhBE). During a
three-year project managed by the EGT, the potential of
underground energy in different parts of Estonia will be investigated in more
detail, and two pilot plant for underground energy will be built. The
research project will last until the end of 2024; the budget is 3.8
million euros and is financed from the sale of greenhouse gas quotas."
5. What is the potential we could "squeeze out" from implementing geothermal heat in Estonia?
"In
Estonia, geothermal heat has the potential to be an important source of
renewable energy. Although it is difficult to estimate the exact maximum
potential, then the overall potential is still significant. It is due to the fact that we can use both the conventional heat from subsurface but also seawater from the capital Tallinn to nearby located Paldiski town region and also the water accumulated in the closed mines at Ida-Virumaa mining areas in the eastern Estoina."
