Developing clean cold tech

While truck propulsion engines are tightly regulated in the EU and increasingly clean, the secondary ‘donkey engines’ used to power TRUs on many trucks and all articulated trailers are effectively unregulated and emit grossly disproportionate amounts of toxic air pollution.

Green engine developer Dearman said it was encouraging that two of the six companies on the shortlist of the 2014 SMMT Award for Automotive Innovation are developing cooling technologies to reduce the impact of the polluting secondary diesel engines used on most refrigerated trucks today.

With investment in cold logistics booming around the world, it is a timely recognition of the inevitable damage to the environment and human health if the exponential growth in diesel refrigeration goes unchecked, and of the arrival of a potentially multi-billion pound market in ‘clean cold’ technologies.

Over the course of a year, a modern trailer TRU emits six times as much nitrogen dioxide (NOx) and 29 times as much particulate matter (PM) as the Euro VI propulsion engine pulling it around.

Carrier Transicold, part of the US giant United Technologies, has developed a diesel-fuelled system incorporating CO2 in place of conventional synthetic refrigerants, now being trialled by Sainsbury’s.

The Dearman Engine Company, a British start-up, received Highly Commended status in last night’s awards and is developing a zero-emission engine to completely replace incumbent diesel fuelled transport refrigeration systems.

Dearman’s highly efficient refrigeration system extracts both cooling and power from the phase-change expansion of liquid air or liquid nitrogen. The system is based on a novel piston engine invented by Peter Dearman in his garden shed in Bishop’s Stortford, and would repay its investment in under three months.

The Dearman Engine Company is working on the first application of the engine with Hubbard Products, to drive the motor in a TRU. Part of the worldwide Zanotti group, Hubbard Products is the UK’s principal designer, manufacturer and supplier of refrigeration systems and units and the leaders in refrigeration for commercial vehicles and refrigerated vans. The technology will be undergoing on-vehicle trials in December at MIRA (formerly the Motor Industry Research Association), which will be followed by commercial trials in 2015 and the manufacture of the first engines in 2016.

Hubbard’s managing director, Pat Maughan, said: “Hubbard, after many years of refining designs, has realised that near-term future requirements cannot be achieved with existing available components and technologies. Hubbard has engaged jointly with Dearman to develop a transport refrigeration system that will be the paradigm shift to economic clean cold on the highway.”

Because diesel TRUs are so polluting, the impact of even a modest fleet of Dearman units could be huge. A recent report from the Liquid Air Energy Network (LAEN) found that a projected fleet of just 13,000 Dearman liquid air refrigerated trailers would reduce NOx emissions by the same amount as taking 80,000 Euro VI trucks or 1.2 million Euro VI diesel cars off the road. It would be the PM equivalent of removing 367,000 such trucks from service – more than three times the entire UK articulated truck fleet today – or 2.2 million Euro VI diesel cars.

The implications of this technology are global. In the UK, online food shopping is growing fast, with the market set to double in value over the next five years to £13 billion according to market researchers IGD. If the additional refrigerated vehicles needed to deliver all this food are not made more eco-friendly, the environmental and health impacts in urban areas could be serious.

The Dearman engine can also offer global benefits, particularly in rapidly industrialising countries where the cold chain is not yet fully established such as India. Here, up to 50 per cent of perishable food is lost before ever reaching a plate because cold chains are rudimentary or non-existent. By using this technology these countries can leapfrog the wasteful and polluting ways of the developed nations.