Leeds City Council is to investigate the impact on air quality that diesel-powered transport refrigeration units (TRUs) have on its urban areas.

Working with clean, cold technology firm Dearman, the council has been awarded a £150,000 Defra grant to identify the level of harmful emissions from TRUS and encourage uptake of cleaner alternatives.

TRUs are typically used by supermarkets and logistics operators to keep food produce cold while in transit. The cold is often powered by a second diesel engine, with an estimated 84,000 TRUs on Britain’s roads.

Dearman estimates that over the course of a year, a TRU powered by a secondary diesel engine can emit up to six times as much nitrogen oxide (NOx) and almost 30 times as much particulate matter (PM) as a Euro-6 HGV engine.

In Leeds, it is estimated that TRUs emit 71 tonnes of nitrogen oxide and 9.5 tonnes of particulate matter per year.

Replacing Leeds’ diesel-powered TRUs with zero-emission alternatives would be the NOx equivalent of removing 2,446 Euro-6 HGVs from the roads, and the PM equivalent of removing 13,024 HGVs, according to Dearman.

The project

Leeds will use the funding to measure emissions from conventional fossil-fuelled TRUs in real-life operations, estimate the number of refrigerated vehicles in use and understand typical duty cycles.

Findings will be analysed with an evidence base established and tools developed for helping reduce the impact of TRUs on local air quality.

The council will  look to install the supporting refuelling infrastructure to enable a multi-vehicle field trial of a zero-emission liquid-nitrogen-powered cooling system developed by Dearman. 

It is hoped this will also add to encourage wider uptake of the technology.

Councillor Lucinda Yeadon, Leeds City Council, said: “Reducing pollution from refrigeration units in the city could see a significant improvement to our air quality.

"This project could lead to significant improvements, not just on Leeds roads, but those around the country.”

Dearman deputy chief executive Michael Ayres added: “We have developed a patented zero-emission engine, currently undergoing advanced road trials, which would significantly cut emissions compared to polluting diesel engines.

“In Leeds and around the country, there are growing calls for tighter regulation of transport refrigeration units. This means the industry needs to start preparing and this is where Dearman can help.”