Geothermal energy could help central and eastern Europe break away from coal and gas, but it needs a quicker uptake and government backing to help meet renewable energy targets, advocates say.
Countries like Hungary, Slovakia, Austria, Romania and Croatia sit over the Pannonian basin, which has huge potential for geothermal energy and is over 10°C per kilometre hotter than the European average, making them a prime location for geothermal deployment.
Moreover, district heating systems inherited from Soviet times mean much of the infrastructure required for geothermal heating already exists.
Martin Hojsík is a member of Renew from Slovakia. According to him, geothermal has massive potential in the region, not just to replace coal, but as a primary source of energy, particularly for heating and cooling.
“We can cash in on it and leapfrog to green technologies rather than sink investments into gas. But there is a risk and there is massive pressure from the gas lobby in central and eastern Europe [to say that] gas is a bridging technology,” he said.
Gas emits around half the amount of carbon dioxide spewed by coal when burned in a power plant. For that reason, it is often touted as a transition fuel for coal-reliant countries in central and eastern Europe.
But according to advocates, geothermal could accelerate the coal phase-out, and shorten the intermediary step of natural gas.
“If we intend to fulfil climate targets, we need to start working on a larger number of geothermal projects as soon as possible to reduce the time necessary for shifting from natural gas,” said Igor Kocis, co-founder and CEO of GA Drilling, a deep geothermal company based in Slovakia.
Geothermal across central and eastern Europe
Large-scale geothermal energy has long been constrained to volcanic areas where heat can easily be captured and turned into electricity. But breakthroughs in deep drilling techniques are now opening new horizons for the technology, offering the prospect of “geothermal anywhere”.
The downside is that deep geothermal is also inherently riskier than other renewable technologies, like solar and wind. In France, a geothermal company admitted responsibility after a series of earthquakes hit the Strasbourg region last December, including one of 3.5 magnitude. The following day, authorities announced they would permanently close down the plant – a €90 million project.
But the relative ease of access to natural heat sources in the Pannonian basin means the region is ideally located for deep geothermal.
According to Kocis, the speed at which geothermal can replace fossil fuels in the region depends on how fast the technology can be tested and deployed. To do that, he calls for an increase in pilot projects in the coming years, so that large-scale commercial plants can be built as of 2030 which can then retrofit coal.
Phase out dates for coal vary between countries in central and eastern Europe, with Austria choosing 2020, Slovakia aiming for 2023 and Hungary 2030. Countries like the Czech Republic and Poland have no phase out date yet.
In Hungary, which has the largest potential for geothermal energy in central and eastern Europe, most of the district heating is currently fuelled by fossil gas, with geothermal providing only 4%.
According to the Hungarian government, there are currently 23 geothermal plants across the country with an installed capacity of 223.36 MW. These include thermal water town heating, district heating and a binary power plant.
According to the IEA, Hungary has a large amount of data from drilling and a long experience with geothermal. The country also has a large infrastructure for district heating with 220 networks and 648,500 flats supplied. Issues include inefficient systems, unfair competition with subsidised gas and regulatory gaps at national, regional or local level.
Both Croatia and Austria also have large potential to develop geothermal energy, particularly at the Hungarian border. Croatia issued four licenses to explorations in the summer of 2020 while Austria has been utilising geothermal energy since the late 1970s and now has a capacity of 95.1 MW for electricity and around 1,000 MW for heat pumps.
In Slovakia, there are currently four geothermal projects to fuel district heating systems. But those are yet to produce electricity, despite three deep wells drilled and permits in place for a plant near the largest city in eastern Slovakia, Košice.
“Košice is a sad example of how the region has been treating geothermal energy as a potential source of energy,” said Hojsík. It is currently idle, meaning the town instead uses coal, often imported from Russia.
The plant was built in the late 1990s and has an energy potential of 20 MW. However, it needs large investment to build a 16km pipeline to connect Košice, which has a population of 260,000 to an extensive district heating system.
The Slovak government has expressed strong interest in helping the potential of geothermal there and a project is seeking to utilise the geothermal heat.
One problem is that the Slovak electricity grid in was closed in 2013, prohibiting the entry of new energy sources. Alongside this, the feed-in tariff of geothermal has declined so much that it is no longer feasible for investors.
Like Hungary, Slovakia also faces issues with funding. Geothermal plants cannot access EU funds thanks to issues on the Slovak side.
Slovakia could help the development of geothermal by categorising geothermal drilling less strictly in its environmental impact assessments and making EU grants more accessible, according to Michal Mašek, project manager at PW Energy Company.
On the European level, he called for a focus on identifying regions with good geothermal potential and both direct and indirect support for companies willing to use geothermal energy.
[Edited by Frédéric Simon]