BRISTOL-BASED ENERGY technology company G-volution has successfully carried out the first live demonstration project using BioLPG and diesel to power a freight locomotive. BioLPG is a co-product of the biodiesel production process, which uses a blend of waste, residues and sustainably sourced materials. During the refining process, a variety of ‘off-gases’ are produced that contain biopropane, which is then purified to make it identical to conventional LPG. The trial was carried out in partnership with Calor, Network Gas and Colas. Network Rail loco No 73592, which is operated by Colas, was fitted with additional fuel tanks for the project. G-volution’s optimiser control unit enables the precise reduction of the quantity of diesel injected into the engine and replaces it with renewable BioLPG. The project has been funded by Innovate UK and the Department for Transport and has been set up to show that cleaner fuels will enable the rail freight industry to operate in a more sustainable and cost-effective way.