Highways England is accelerating the use of warm mix asphalts as standard across its supply chain as part of a drive toward net zero carbon emissions.
The Government-owned company has been using the material since 2015 and a collaborative programme with the supply chain and extensive research now means it can be used freely across the Strategic Road Network (SRN).
Previously requiring an application for a departure from standard, Highways England is now asking all those involved in the construction and/or maintenance of the strategic road network, particularly designers and main contractors, to use warm mix asphalts (WMAs) as it moves towards net zero.
WMA technologies can offer enhanced efficiencies and lower production carbon, with CO2 savings of up to 15% when compared to conventional hot mix asphalts.
While typical asphalts are produced at up to 190°C, the simple principle behind WMA technologies is to manufacture asphalt at reduced temperatures but with additional additives, thereby using less energy and delivering meaningful carbon savings, without compromising performance.
Produced at temperatures up to 40°C lower than traditional asphalt, if all production in the UK switched to WMAs, it would save around 61,000 tonnes of CO2 a year, the equivalent of cutting around 300 million miles of car journeys.
It would also help save up to £70 million a year through an increased in shift outputs and can be recycled back into new asphalts, preventing waste. WMAs can be laid using existing equipment.
Malcolm Dare, Executive Director of Commercial and Procurement at Highways England, said: “This is a big step forward for Highways England that allows us to not only achieve huge efficiency savings but also reduce carbon as we strive for net zero.
“Carbon reduction, along with ensuring our roads provide smooth, safe, and efficient journeys for motorists, are key and something we are constantly striving to improve for generations to come.
“That’s why we are altering our way of working to encourage and enable the use of warm mix asphalts as standard across the supply chain, which has efficiency, sustainability, and health and safety benefits whilst not compromising performance.”
According to an All Party Parliamentary Group on Highways’ report in September 2019, WMAs account for significant volumes worldwide – almost 40% of asphalt production in the USA and over 15% in France – but WMAs remain under-used in the UK, where they currently represent less than 4% of overall asphalt production. At Highways England, WMAs previously required an application from the supply chain for a departure from standard.
Paul Gott, Project Sponsor from Morgan Sindall Infrastructure, said: “Warm mix asphalt is the first carbon efficiency project on the groups extensive carbon reduction plan, which is evolving and already identifies several short, medium and longer-term goals.”
Malcom Simms, Director of the Mineral Products Association, added: “This is a significant first step on our collective and challenging net zero journey, and it’s great to see lower carbon asphalts being enabled as a matter of routine, rather than by exception.”
Highways England’s net zero carbon plan will see it rapidly cut carbon from road construction, maintenance and operations, and support the transition to zero emission vehicles.
