Closed-loop Deep Borehole Heat Exchanger: Newcastle Science Central Deep Geothermal Borehole

In the effort to mitigate climate change, the UK is pursuing a low-carbon economy aimed at reducing greenhouse gas emissions to net zero by 2050. A key strategy in this drive is increasing the share of renewable energy sources. Deep (>500 m) geothermal energy has significant potential to decarbonise heat, but has been largely under-exploited in the country, partially due to perceived risk profile and high initial drilling cost. The latter might be offset by repurposing existing wells, including abandoned hydrocarbon wells (although these are associated with specific risks and challenges). The Newcastle Helix – a hybrid state-of the-art city quarter at the heart of Newcastle – has an existing geothermal exploration borehole of 1.6 km depth, which could be repurposed as a single-well closed-circulation geothermal system. In this paper, numerical modelling of the Newcastle Science Central Deep Geothermal Borehole is presented, aiming to simulate its thermal response in the hypothetical case of its refurbishment as a closed-loop deep borehole heat exchanger. This study is part of the ongoing “NetZero GeoRDIE – Net Zero Geothermal Research for District Infrastructure Engineering” project