Nitrogen engines could be a cool way to improve city air quality


Engines powered by liquid nitrogen could significantly reduce air pollution and are cost effective, a new Leeds City Council-backed trial has found.

Rolled out across Leeds, theground breaking technology could lower air pollution emissions by 19 tonnes every year, according to the study.

Liquid nitrogen engines, developed by technology company Dearman, are designed to power transport refrigeration units used in lorries to keep food and other goods cold in transit.

Currently TRUs are typically powered by diesel engines 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% less greenhouse gases than diesels.

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 nine-month trial was undertaken as a partnership between Leeds City Council, Cenex and Dearman, and it found that the next generation of Dearman TRUs, ready in 2019, will be a about 20% cheaper to run than TRUs powered by unsubsidised diesel.

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.

The trial was backed with a £150,000 air quality grant, awarded to Leeds City Council last year by the Department for Environment, Food and Rural Affairs (DEFRA).

Leeds Cllr James Lewis said: “Leeds City Council is committed to tackling air pollution in order to protect the health of everyone in Leeds.

“New technologies will play a key role in enabling the council to reduce air pollution in the shortest possible timescale. Because of this, we are actively involved in several innovative trials just like this one.

“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.”

Scott Mac Meekin, CEO of Dearman, added: “We are pleased to have led this trial with a leading supplier of ice products who should be commended for reviewing its local environmental footprint.

“Leeds City Council has rightly identified second diesel engines on delivery lorries as a particular source of air pollution. This trial has given the council the evidence it needs to encourage government to take real action and support a switch to zero-emission alternatives instead.”