As Steve Carroll reports, the results from the UK DfT’s Low Carbon Truck Trial seem to clear a path for low carbon HGVs

Freight transport is vital to economic growth, but also has significant environmental impact. Heavy-goods vehicles (HGVs) make up around 17 per cent of UK greenhouse gas (GHG) emissions from surface transport. Reducing emissions from road freight is expected to be very challenging and it will be very difficult for the UK to meet its goal of an 80 per cent reduction of GHG emissions from 1990 levels by 2050 without a major cut in GHG emissions from HGVs. It will likely take a combination of interventions. However, there is currently limited evidence of the cost-effectiveness, GHG abatement potential and wider impact (e.g. air quality) of available interventions.

The Department for Transport (DfT), the Office for Low Emission Vehicles (OLEV) and Innovate UK (formerly the Technology Strategy Board) co-funded the Low Carbon Truck Trial (LCTT), through which the UK government provided £11.3m to promote procurement of low emission HGV technologies and their supporting infrastructure. The DfT then commissioned Atkins and Cenex to collect and analyse data to demonstrate the impact and benefits of using the alternatively fuelled trucks deployed through the trial across a range of freight operations.

Key points of the LCTT
The trial comprised 12 consortia projects undertaken by 35 participating companies, including fleets, emission-testing companies, station providers, universities and product developers. These projects deployed more than 370 low carbon vehicles, including dual-fuel vehicles, dedicated bio-methane and natural gas vehicles and some trucks running entirely on used cooking oil. In addition, 15 refuelling stations were commissioned or upgraded across the country.

The LCTT met its original key objectives, which were to facilitate alternatively fuelled truck learning, product development and initiation of a publicly accessible UK gas refuelling infrastructure. It has provided a rich and valuable data source to assist policy-makers in evaluating the technologies within the trial, as well as feedback to the fleet community to give them the knowledge to make informed choices within their fleets.

Trial highlights
Technology selection was challenging for fleet operators. When looking to make technology purchases (vehicles or stations), fleets reported a lack of independent information and available guidance on the performance of alternative technologies.

CO2 performance was variable across the trialled technologies. The best-performing dual-fuel diesel/gas systems offered CO2 savings of up to 10 per cent TTW and 6 per cent WTW. The biofuel blend had a significant effect on truck-emission performance. When operating using only natural gas, the dedicated gas vehicles and some of the diesel/gas dual-fuel systems showed increases in CO2 emissions against their real-world diesel comparator vehicles. Biofuel use was a key factor in enabling a step-change improvement in CO2 emission savings.

Emission testing undertaken by consortia highlighted that relatively large amounts of methane were present in the exhaust gas streams of dual-fuel diesel/gas vehicles, which gave these trucks higher total GHG emissions. This highlights the need for better understanding and evaluation of the total GHG and air-quality effects of different technologies under real-world driving conditions before policies are set in favour of certain technologies. Policies should also consider how the environmental impact of retro-fit technologies are managed and enforced.

Two consortia showed that air-quality performance was generally improved with dual-fuel diesel/gas systems. One system showed reductions in all air-quality pollutants (CO, NO, NO2, PM, NOx), and another showed emissions reduction in some air-quality pollutants, but with increases in CO and variable PM performance.

The trial systems increased the unplanned downtime of the trucks by 19 per cent. However, this varied significantly by technology type. Fleet managers rated reliability as a minor implementation barrier, generally accepting that the introduction of new technology would involve a learning curve for both fleet operators and system suppliers. New stations funded under the LCTT proved very reliable, achieving an average of 99.4 per cent availability. This contrasted with some legacy gas stations in the UK, which predated the LCTT.

Future developments
At the time of undertaking stakeholder interviews (February 2016), the gas-truck industry was experiencing limited growth, awaiting increases in Euro VI vehicle availability and the recovery of the diesel and gas price differential. The industry and fleets generally felt that alternatively fuelled truck numbers were set to decline if further financial support was not provided to help bridge the gap to larger-scale commercialisation. OEMs and retro-fit technology providers stated that they were progressing the supply of more Euro VI products. For example, OEMs are improving the efficiency of dedicated gas vehicles and increasing their product range available in the UK, with 400 hp trucks now available and 450 hp trucks expected in 2017.

Next Steps
The value of large scale demonstration and evaluation trials, such as the LCTT, was confirmed in January 2017 when the Government announced the winners of the follow-on activity – Low Emission Freight and Logistics trial, which will see the deployment and testing of over 300 new and innovative low emission freight vehicles.

Case Study – delivering refuelling infrastructure
Environmental Efficiency sought to commission a “daughter” station to its CNG mother station in Crewe, Cheshire by June 2013. In July 2014 the company was refused planning permission at a location in Derbyshire, and identified a new site outside of Scunthorpe. The daughter station opened in November 2015 and operates with one tube trailer, with an option for hiring a second trailer. Refuelling requires a 10-hour round trip to Crewe. In total it took 18 months to obtain planning permission between the change of site and issues with third parties and the planning process. In hindsight Environmental Efficiency has highlighted the need to plan for earlier engagement with local communities to explain how the technology works, so they can overcome objections relating to concerns about an increase in vehicle movements and safety of the technology. Mitigation measures such as vehicle curfews and educational videos have been developed to help with this.

HGVs contribute nearly 20 per cent of GHG emissions from road transport in the UK today. This trial highlights the importance of running large-scale technology evaluation trials and demonstrates how investment in the right technology and infrastructure can significantly reduce the impact large-vehicle fleets have on our country’s overall emission levels.

Steve Carroll is Head of Transport at Cenex. Cenex is the UK’s first Centre of Excellence for Low Carbon and Fuel Cell technologies and operates as an independent not-for-profit consultancy and research organisation. It specialises in the delivery of projects which support innovation and market development to accelerate the shift to a low-emission economy.