UK Oil & Gas (UKOG) and Ceraphi Energy are planning a joint venture to develop part of UKOG’s Horse Hill oil site in Surrey into a geothermal energy hub.
Surrey County Council granted Horse Hill Development Ltd (HHDL) planning permission for four new oil wells at the site, expected to produce for 20 years, in September 2019 – a decision that is currently the subject of an appeal, which was heard by the High Court in November. Horse Hill was initially talked up for its oil extraction potential by UKOG, but when production began in 2020 it was said to be less than planned. In UKOG’s 2021 annual report chairman Allen Howard said “In addition to the constant and mounting regulatory workload, the oil field’s geology has proved unexpectedly complex.”
Currently at a conceptual stage, the geothermal hub would aim to generate and supply more than 200,000MWh/yr, mostly as heat energy. The project’s first phase would aim to supply significant industrial end-users in the locality with 100% green heating and cooling plus ancillary green electricity or hydrogen. As in established heat networks, heat would be delivered to the end user via a small diameter hot water pipe and heat pump system. Further wells or sites could be added to supply other users. Once the joint venture is signed, conceptual engineering design and preparation of a planning application expected in the New Year.
The so-called ‘GeoHub’ would have six new deep geothermal boreholes. They would use Ceraphi’s proprietary closed-loop downhole heat exchanger technology, which the company says requires no injection or circulation of water, eliminating the possibility of induced seismic activity. Siesmic activity has been a concern of local residents after a series of events in 2018 that it was feared were caused by oil drilling.
UKOG said that also, once current oil production at the site reaches the end of its economic life those boreholes too would be repurposed to add further geothermal baseload.
Chief executive Stephen Sanderson, said: “It makes perfect sense for the UK to harness the abundant green heat energy beneath our feet to heat, cool and power our homes and industry. The GeoHub’s weather independent target baseload is firmly in line with both the UK government’s ‘build back greener’ strategy for net-zero and the company’s ambition to transition its UK assets into sustainable green energy hubs. We look forward to working with Ceraphi to further define and deliver the project.”