A project that will trial the use of geothermal energy as a means to regulate the temperature of UK roads has been announced.
The initiative could keep roads from melting in the summer and freezing in the winter, therefore preventing the creation of potholes and improving road safety.
Researchers from National Highways and the University of Surrey will use ground source heat pumps to cool roads in the summer and warm them in the winter.
Ground source heat pumps would be installed under the UK's road network
Project lead Dr Benyi Cao’s team plans to work with advanced materials engineering company Versarien to develop a new graphene-enhanced microcapsule that can dig into the soil beneath the surface when roads are resurfaced to improve heat conduction and storage by installing ground source heat pumps.
The researchers will also create a laboratory-scale model road segment with a heat pump in the University of Surrey’s advanced geotechnical laboratory. The model will allow Cao’s team to evaluate the thermal performance and resilience of roads under controlled climatic and traffic loads.
Heat would be used to stop potholes and heat homes
The heat that is collected from the heat pumps was suggested as a way to regulate homes as well as road temperatures.
“At the moment, a typical motorway or A-road surface lasts 20 years, but this is likely to reduce as extreme weather increases,” Dr Cao said. “However, by regulating the temperature of road surfaces, they should last significantly longer. Aside from the safety benefits and reduction to car damage, think of the reduction in expensive, inconvenient roadworks.”
He adds that potholes on England’s major roads have caused 5,000 injuries since 2018 and the nation spent £1.2 billion on road maintenance and repair, with the Asphalt Industry Alliance (AIA) estimating that a further £14 billion is needed to fix the backlog of repairs needed on British roads – which would take 11 years to complete.
While half (51%) of local roads are reported to be in good structural condition, the remaining 100,000 miles could continue to deteriorate to the point of needing to be rebuilt within the next 15 years, the report warned.
In addition, the repairs could have a damaging impact on the environment, as current road repair technology has been estimated to create 700,000 tonnes of CO2 each year.
£800,000 study will test how feasible project might be
The project has been awarded a £800,000 research fellowship from the Royal Academy of Engineering, with the hopes it could improve how major roads across the UK are maintained and upgraded – even as climate change “increases the challenge of keeping them fit for purpose,” the university said.
The final step of the project aims to introduce full-scale field trials on UK roads and conduct a full life cycle assessment to understand the environmental and financial costs of thermo-active roads.
“Climate change poses an extra threat to our roads,” Cao said. “Thermo-active roads could help mitigate this.
“They could be introduced gradually as resurfacing takes place, so wouldn’t cause any extra disruption for motorists. I think there will be long-term benefits to drivers and taxpayers.”
For more information on ground source heat pumps, read our article outlining how much space does a ground source heat pump need.
