Construct - Issue 49

Project

GOING ELECTRIC

AN IMPORTANTMILESTONE ONTHE JOURNEY TONET ZEROHASBEENACHIEVED WITHANALL-ELECTRIC TRIAL INMERTON

The London Borough of Merton’s target to achieve net zero carbon emissions by 2050 aligns closely with the carbon goals of its long-time highways partner FM Conway. In support of this aim, the two organisations have collaborated on a low carbon resurfacing project involving the most electric plant ever deployed on a UK public highway scheme. “Achieving net zero in road construction is challenging due to the carbon footprint of bitumen and traditionally diesel-powered machinery,” explains London Borough of Merton highway engineer Gary Marshall. “We have trialled different products, and a limited use of electric hand tools, but I was keen to know the carbon reduction potential if we looked at all the activities on a scheme.” and footways needed resurfacing. The carriageway work involved planing 40mm and replacing it with a warm mixed dense surface course material containing 30% recycled asphalt product (RAP). The entire process was delivered using electric plant: a Sany electric planer, a Dynapac Electric City Marian Road, a 300m long residential street, was chosen for the trial as both carriageway

paver and a Dynapac CC1000 fully electric roller.

All plant and hand tools on the project were electrically powered

The new hand-laid footway consisted of a cement-bound granular basecourse, a binder layer incorporating 80% RAP, and a dense surface course with 60% RAP. All power hand tools used for the footway reconstruction were electric, including disc cutters for the kerbs and a compaction plate. “We’ve carried out numerous low-carbon schemes that focused on decarbonisation through materials innovation, but our focus here was to reduce the carbon associated with the surfacing plant,” explains FM Conway carbon manager Muhammad Ikram. “Despite being a small contributor to the overall carbon, it is one of the more difficult areas to decarbonise.” Swapping from diesel to electric cut the carbon associated with plant and equipment on the project by 95%, contributing to a total saving of 16.7tCO 2 e. FM Conway surfacing director Paul Padfield says: “We’re always exploring greener solutions for our clients. Trials like this help us understand what we can achieve and are an important step towards net zero.”

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