Leeds trial demonstrates benefits of liquid nitrogen engines

According to a recently completed trial backed by Leeds City Council the widespread adoption of liquid nitrogen engines for powering refrigeration units in lorries could reduce air pollution emission across the city by 19 tonnes every year.

liquid nitrogen engines
The Dearman engine installed on a delivery vehicle as part of the Leeds trial

Liquid nitrogen engines, developed by technology company Dearman, are designed to power transport refrigeration units (TRUs) used in lorries to keep food and other goods cold whilst it is on the road.

Currently, TRUs are typically powered by diesel engines that are not subject to the same emissions standards as a vehicle’s main engine. As a result, these secondary engines can emit up to six times the amount of air pollution.

In contrast, Dearman’s innovative liquid nitrogen TRU engines emit no air pollution whatsoever and up to 80 per cent less greenhouse gases than dirty diesel engines.

Based on technology invented by self-taught UK engineer Peter Dearman, the Dearman engine harnesses the rapid expansion of liquid nitrogen to deliver zero-emission power and cooling.

As previously reported, the technology has already been trialled by UK supermarket chain Sainsbury’s which, in 2016, became the first company in the world to introduce a refrigerated delivery lorry cooled by a liquid-nitrogen-powered engine.

Running a vehicle equipped with a Dearman liquid nitrogen TRU as part of the fleet of a Yorkshire-based logistics company, the real-world emissions from a truck running with the new technology and from a truck running with a TRU using conventional fossil fuel were compared.

The trial was undertaken as a partnership between Leeds City Council, Cenex and Dearman and was backed with a £150,000 grant from the Department for the Environment, Food and Rural Affairs (DEFRA).

Dearman and Leeds City Council will use the trial data as evidence in a bid to tackle the impact that TRUs have on local air quality. The results of the trial will also be further disseminated to support other local authorities keen to tackle emissions.

Commenting on the trial James Lewis, Leed’s council’s Executive Member for Environment and Sustainability said: “New technologies will play a key role in enabling the council to reduce air pollution in the shortest possible timescale.  We will now work with the government to encourage the rollout of this new technology so that residents in Leeds, and across the country, can enjoy the benefits of cleaner air.”