Research and analysis

Emissions testing of gas-powered commercial vehicles

A project to gather real-world data on methane slip and air quality pollutant emissions from gas and dual-fuelled commercial vehicles.


Emissions testing of gas-powered commercial vehicles

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There is considerable interest amongst fleet operators and gas suppliers in the use of methane as a road fuel, either in its fossil fuel form as natural gas or as a biofuel, bio-methane.

It attracts lower fuel duties than diesel and offers the potential for air quality benefits and lower greenhouse gas (GHG) emissions. However, there is currently a limited evidence base on the cost effectiveness, carbon reduction potential and wider impacts (eg air quality) of available interventions.

This project has used a protocol, developed in 2015 for DfT, to test greenhouse gas and air pollutant emissions from range of gas and dual-fuelled (diesel / gas and diesel / LPG) HGVs.

It highlights a range of policy considerations and makes recommendations for further tests.

The £11.3 million low carbon truck trial has part-funded industry consortia to purchase and trial alternatively-fuelled vehicles, the majority of which were dual fuel (diesel / gas), and to commission refuelling infrastructure.

Published 9 January 2017