The HS2, a high-speed railway network under construction in the U.K., reports that results from a trial carried out to test the potential air quality benefits of alternative fuels look set to help its efforts to push to cut the use of diesel and introduce low-carbon solutions on construction sites.
The trial, part of the concern's Innovation program, was carried out in partnership with Imperial College London and Balfour Beatty VINCI (BBV) at an HS2 construction site near Coventry, U.K., in April 2021. It measured tail-pipe emissions to determine the potential emission benefits of using alternative fuels when compared to red diesel.
The ‘real-world’ emission measurements tests were carried out on two 20-ton excavators, a Liebherr R920 compact excavator (Stage IIIB) and a Komatsu PC210 excavator (Stage IV). The fuels tested included standard red diesel (EN590) to provide a baseline for comparative purposes, red diesel with F18 fuel additive and two biofuels: hydrogenated vegetable oil (HVO) and Enhanced HVO.
While the results showed limited air quality benefits when compared to red diesel, the trial demonstrated the potential carbon reduction opportunities through the sustainable sourcing of alternative fuels, the railway network says.
Both machines used during the trial had exhaust gas aftertreatment technology installed to reduce nitrogen dioxide and particle emissions. As such the study also recognizes that older machines with no aftertreatment technology may have a greater potential for reducing emissions through the use of alternative fuels.
“HS2’s extensive innovation program is aimed at supporting the transition from diesel to zero emissions by developing alternative technologies.On-site trials provide a real-world testing environment and are important to inform future solutions," said Neil Wait, head of environmental sciences for HS2. "While this testing showed limited air quality benefits from the use of biofuels, it’s clear that they are part of the construction industry’s transition to low carbon solutions, with potential CO2 savings that can be achieved through the sustainable sourcing of raw materials used in the fuels.
“The research findings support steps taken by HS2 contractors to exploit the potential of biofuels to reduce carbon impacts on our construction sites," Wait said. "We continue to work closely with our supply chain and research organizations to develop far-reaching sustainable alternatives which will change the way the construction industry operates and support Britain’s move to a zero-carbon future. These include fully electric solutions, solar and wind power, hydrogen technologies, retrofits on older machines, along with increasing delivery of materials by rail.”
The study recommends that where biofuels are being used, they are in line with the Renewable Transport Fuel Obligation (RTFO), which regulates biofuels used for transport and non-road mobile machinery. It also recommends that biofuel providers should be registered with recognized assurance schemes such as the Zemo Partnership Renewable Fuels Assurance Scheme.
Source: HS2
