Polluting diesel fridges could face clampdown

By Categories: NewsPublished On: Wednesday 5 April 2017

A Budget call by the chancellor Philip Hammond for evidence on the impact of the use of duty-rebated (‘red’) diesel in urban areas, and its fiscal and environmental impacts, has led a University of Birmingham professor to claim that the days of diesel-powered refrigeration units on trucks are numbered.

There is concern that while truck engines themselves have controlled emissions – and an increasing number of cities across Europe, including London, are seeking to impose further restrictions on the use of diesel-engined road vehicles – the exhaust fumes from the small diesel engines powering the fridge units on trucks used for temperature-controlled distribution are completely untreated and unregulated.

Tony Peters, who is visiting professor in power and cold economy at Birmingham University, pointed out that such transport refrigeration units (TRUs) are classed as ‘non-road mobile machinery’, even though they operate on a truck or a trailer – thereby allowing them to be run on red diesel without falling foul of the law.

Professor Peters said that there was “no conceivable economic justification” for allowing such subsidies to continue for such a polluting technology, given the availability of new competing zero-emission systems.

Indeed, industry sources have estimated that the emissions from the 84,000 diesel-powered fridges currently on UK roads are the equivalent to those from about half a million Euro 6 trucks (Transport Operator, 61).

Professor Peters said: “Analysis has shown that these independent transport refrigeration units (TRUs) can emit six times as much nitrogen oxides (NOx) and 29 times as much particulate matter (PM) as the Euro 6 propulsion engine dragging them around.

“Compared to the official emissions limits of a modern Euro 6 diesel car, the TRU emits up to 93 times more NOx and 165 times more PM.”

He said the disproportionately high emissions had “evaded the radar for many years”, but that policymakers at the Department for Environment, Food & Rural Affairs (DEFRA) were now beginning to acknowledge the issue.

“TRUs were mentioned in both DEFRA’s Clean Air Zone Framework published last autumn, and the Clean Air Bill, which reaches second reading imminently,” he said. (The reading is currently scheduled for 12 May.)

“Both make clear that TRUs will be covered by the new national network of clean air zones. DEFRA talks of ‘encouraging the upgrade of refrigeration units on cold chain vehicles to the least polluting options’, while the Clean Air Bill calls for TRU use to be ‘restricted in specified urban areas.’”

Professor Peters added that the TRUs represented an easy target for legislators because of the relatively small number of engines.

“Come election time, businesses don’t have a vote; private motorists generally do,” he warned.

He called for legislative reform to prevent such units running on rebated diesel as a first step towards cleaning up the temperature-controlled logistics industry.

“Britain is one of only a handful of countries in the EU that still permits it,” he said.

“This loophole is unlikely to survive the intensified scrutiny the introduction of Clean Air Zones is likely to bring.”

He warned that: “Air pollution regulations will soon be toughened to meet the scale of the challenge, and refrigerated transport will not escape. At some point operators will be forced to act by the combination of rising public awareness and regulatory pressure.

“Companies that want to demonstrate they are responsible corporate citizens would do well to embrace this opportunity early, not as the laggard who did the right thing only when compelled by regulation.”

Not all truck fridges use independent diesel engines. The combination of a Euro 6 truck and a direct-drive fridge can produce lower emissions, while zero-emissions options are gaining increasing prominence.

For example, a TRU pioneered by a partnership between clean cold technology specialist Dearman and cooling equipment provider Hubbard Products utilises liquid nitrogen power to eliminate NOx and PM emissions, while also reducing noise pollution and carbon footprint.

The system has been undergoing a trial with supermarket giant Sainsbury’s since last June (see image opposite), and Dearman says that further international deployments are expected to begin later in 2017.

In the light commercial sector, meanwhile, fleet services and contract hire provider Fraikin has been named the exclusive leasing partner in the temperature-controlled sector for a new silent-running, zero-emissions battery system from power solutions supplier Perpetual V2G.

Fraikin is making a demonstrator of the technology, which can power the refrigeration units fitted to 3.5-tonne vehicles, available for nationwide trial by fleet operators.

Professor Peters added that some newly designed zero-emission TRUs “materially outperform conventional diesel systems”, so “doing the right thing” may “also [be] good for business”.