What’s happening? The UK’s first deep geothermal plant in 36 years has been inaugurated at the Eden Project in Cornwall. The geothermal well, extending 5 km underground, is supplying heat to the tourist site’s attractions. Despite having significant geothermal resources, the UK has been slower than other European countries in harnessing geothermal energy. The completion of this project is expected to inspire further geothermal initiatives across the country. The well is projected to reduce the Eden Project’s heating costs by 40% and enable year-round food production on-site. The hope is that larger industrial and institutional sites will follow suit, encouraged by the success of this project. (New Scientist)

Why does this matter? The presence of renewables in the UK’s energy mix continues to grow. In 2022, half of the UK’s energy mix was supplied by zero-carbon power for five months. Solar and wind power dominate and are seen as the future foundation of the UK’s electricity generation system. However, to prevent outages, it is important to identify and mitigate possible limitations. For example, without significant battery storage capabilities, solar and wind provide intermittent and inconsistent power supply. Geothermal energy presents itself as a potential solution to mitigate this, complementing and stabilising the renewable power grid.

Location-specific and expensive – Geothermal electricity generation is currently limited to a few locations and is expensive. Typically, in naturally occurring geothermal systems, hot water and steam are extracted from underground to heat homes and businesses or generate electricity. The technology has been deployed since 1904 but is limited to specific areas – for a natural system to be viable, it must possess heat, water and permeability.

Enhanced geothermal systems – New technologies are emerging that could make geothermal energy more widespread and financially viable, such as the advancement of enhanced geothermal systems (EGS). Here, in areas where permeability may be low, a borehole is drilled roughly 1.6 miles, and water is pumped underground. The process increases permeability by opening fissures and cracks in the rock. Once the water permeates through the warm rocks it is then collected by a second borehole, drilled to a depth of around 2.8 miles.

UK potential – In the UK, geothermal hotspots coincide with some of the poorest areas that the government has identified in its “levelling up” strategy. However, there are currently only two active projects in the UK, falling behind much of Europe – around 250,000 homes in Paris are heated by geothermal power, while in Germany, €1bn ($1.1bn) has been committed to 100 projects set to be completed before 2035. The US government are also heavily incentivising geothermal power. By 2035, research and development is expected to drive down the cost of EGS in the US by 90%, powering 40 million homes by 2050.

UK energy transition – More broadly, a recent report authored by former government economist Chris Walker for the UK Business Council for Sustainable Development suggests that the UK could generate £70bn ($88.9bn) annually and become a clean energy exporter to Europe by increasing clean electricity generation by 50% above current projections for 2050. This would create an additional 279,000 jobs and support a total of 654,000 jobs in the UK’s clean energy industries. However, the government needs to address barriers hindering green energy ambitions, such as grid connectivity and storage capacity, to seize this economic opportunity.