HS2 cuts emissions with LPG

6 September 2022

Following a successful trial of a clean air gas engine (CAGE) integrated into a solar-battery hybrid power system in an Advante welfare unit on an HS2 construction site from December 2020, HS2 is trialling an OakTec stand-alone CAGE generator which is said to have delivered significant reductions in emissions.

The system, which uses liquefied petroleum gas (LPG) as a direct replacement for diesel, is being trialled by HS2’s contractor Mace Dragados on a site at Euston and has exceeded its targets.

The generator unit used a vehicle Euro 6 engine platform with emission reduction technologies such as intelligent control of the engine’s operation and exhaust after-treatment systems. The research and development of the engine was funded by Innovate UK through the SBRI (Small Business Research Initiative).

Emission testing of the 24kW rated unit undertaken by Imperial College London showed significant reduction in harmful pollutants, up to 95 per cent reduction in NOx (nitrogen oxides) and particulate exhaust emissions, when compared with the output of a conventional diesel-fuelled welfare unit power system.

Andrea Davidson, HS2’s air quality manager said: “We aim to make the HS2 project net zero carbon from 2035, with the target of having all our construction sites diesel-free by 2029. To achieve these ambitions, HS2 is working closely with UK manufacturers and researchers to trial new technologies, to help encourage the construction sector to move away from diesel and reduce greenhouse gas emissions. 

“The successful results of the CAGE trials are key milestones in achieving this, and we’re looking forward to seeing products like this rolled out across our sites in the future.”

The trial aimed to surpass the Stage V emission standards for non-road mobile machinery. The average emissions from the three load points across the six test cycles for the engine were calculated and compared against three different emission standards in the corresponding rated power band: EU Stage IIIA for constant speed diesel engines (category J); EU Stage V for constant speed diesel engines (category NRE-v/c-3); and EU Stage V for non-hand-held spark ignition engines (category NRS-v-2b). 

● Look out for more news about the use of LPG soon...