Geoscience Ireland (GI) has been deeply engaged in understanding, researching and promoting the Geothermal Energy Sector in recent years. Geothermal Energy is a renewable and sustainable resource for district heating , and at sufficient temperatures, a source for electricity generation.
Reflecting the high temperatures found in the earth’s core, earth temperatures increase with depth, usually at a rate of 25°C per km. Geothermal Energy utilises the geothermal gradient to harvest hot water, either by extraction or by injection and recovery.
Geothermal Energy is generally considered under two headings-; power generation and district heating. Power generation is provided by waters with temperatures of c +130°C, while district heating is provided by waters at lesser temperatures of 50-100°C.
At present, development is largely confined to areas where the geothermal gradient is high i.e., where the cover rocks are thinner above the hottest areas of the subsurface. Areas of lower geothermal gradients can also be developed; they require access by deeper drilling.
The European Union (EU) recognises the potential of GE by supporting research and analysis of commercial aspects of the sector. GI has been a partner in the EU’s COSME funded projects – Geo Energy Europe GEE 1 & 2. These projects bring together European know how , technologies and experience from eight business clusters in seven countries comprising over 600 members. The GEE 2 project is designed to evaluate opportunities for participating companies in exporting expertise and creating business collaborations with a focus on Market Study Visits to four markets- Chile, Canada, Kenya and Costa Rica.
Joe Mongan of GI has co- led these Market Study Visits which have yielded valuable information on the scale and opportunities in these markets. While the GEE2 project was adversely impacted by Covid travel restrictions, member companies have developed business agreements and revenues in these markets, as well as establishing an effective network among GEE2 members.
In Ireland, the potential of Geothermal Energy is being investigated and promoted by Geological Survey Ireland, Geological Survey of Northern Ireland, iCRAG and the Geothermal Association of Ireland.
The absence of a regulatory framework has hindered geothermal energy development. In contrast to the EU average of 23%, Ireland relies on only 6.3% of renewables for its final energy consumption for heating and cooling while Sweden leads at 66%.
Climate Action initiatives have refocused attention on the sector and has seen the inclusion of GE for District Heating in the Climate Action Plan 2021. A number of policy documents have been published in recent years including a GSI Assessment of Geothermal Energy for District Heating in Ireland; a 2020 Non-Technical Roadmap for a Policy and Regulatory Framework and a Draft Action Plan and Draft Policy Statement in 2021. Legislation is planned under a Geoscience Bill by the end of 2023 to deal inter alia with legal, planning and regulatory issues for the sector.
Geological Survey Ireland has dedicated geothermal energy staff and provides technical support to government on technical and regulatory issues. GSI is developing a National Geothermal Database– an important element in de-risking projects. It also engages in public information and engagement. The Irish Centre for Research in Applied Geoscience (iCRAG) also conducts research in the area and supports GSI’s public engagement activities.
Promising projects in Ireland include heating at NUIG, a higher than expected geothermal gradient of 38C at TU Dublin’s Grangegoeman campus and two demonstrator projects in Northern Ireland.