Whilst there is good anecdotal evidence that the climate affects the performance of underground cables, there is limited understanding of the relationship between ambient air temperature, soil type, soil moisture and the temperature at the cable soil interface. This project aims to quantify this relationship, to then couple susceptible soil types with climate projects in different region and thus provide evidence of how areas with underground cables may be disproportionately affected by climate change.

Benefits

The principal benefit of HOTGROUND is the development of an evidence-based methodology that enables Northern Powergrid and other GB network operators to proactively identify locations where underground electricity cables may become increasingly vulnerable to overheating as a result of climate change. Current asset management practices rely largely on historical weather conditions, standard soil assumptions and reactive fault analysis, providing limited visibility of how future heatwaves, drying soils and changing ground conditions may affect underground cable performance.

By integrating historic fault records, climate observations, soil characteristics, land cover information and future climate projections, the project will provide a significantly improved understanding of the relationship between environmental conditions and underground cable thermal risk. This will allow network operators to move from reactive management of heat-related failures towards targeted, risk-based resilience planning.

The expected benefits for consumers include improved network reliability during periods of extreme heat, reduced likelihood of heat-related cable failures and more efficient prioritisation of network investment. Better targeting of resilience interventions will help ensure that future expenditure is directed towards the assets and locations facing the greatest climate-related risks, supporting more efficient use of customer-funded investment.

The project will also generate wider benefits by informing future asset design standards, installation practices and long-term network planning processes. By identifying future hot-spot locations across the licence area, the methodology will support adaptation to climate change while helping maintain secure and reliable electricity supplies for homes, businesses and critical services.

An additional benefit is the protection of consumers in vulnerable situations. Heatwaves have a disproportionate impact on elderly customers, young children and those with medical conditions who may depend on electrical cooling and other essential services. Improving understanding of future cable resilience risks will support more informed investment decisions that help maintain supply continuity during extreme weather events.

As the methodology uses nationally available climate, environmental and asset datasets, the learning generated is expected to be transferable across Great Britain. This provides the potential for benefits to extend beyond the Northern Powergrid licence area and contribute to a more resilient electricity network as climate-related risks continue to increase.