Truck manufacturers lobby for ban on SCR cheat devices
Four years after Transport Operator first raised the issue, truck manufacturers are now lobbying the Department for Transport to get selective catalytic reduction (SCR) bypass devices, which dupe vehicles’ on-board computers into thinking AdBlue has been added to the system, banned from use on trucks on UK roads.
With the VW scandal having thrown ‘real-world’ conformance with emissions regulations into the spotlight, research by Transport Operator has revealed that at least three companies are still offering these devices in the UK. Their sale and/or use is banned in some other countries, including Australia.
Most trucks built from Euro 4 onwards use an SCR system to control NOx emissions. These systems are dependent upon AdBlue being injected into the exhaust upstream of the SCR catalyst where it is converted into ammonia, which then combines with NOx gases to form harmless water, nitrogen and CO2.
The emulator cuts off the supply of AdBlue but fools the truck’s ECU into thinking that the fluid is being dispensed as normal and the truck’s emissions are within legal parameters.
Hard data about the use of such devices is difficult to come by, and operators will tend to remove or disable them before a vehicle is sent in for servicing by a franchised dealer workshop. But one technician who specialises in roadside breakdowns told us that their use on older Euro 4 trucks which had been purchased second-hand was “very widespread.”
“Part of the routine check that we run through when a truck has engine problems at the roadside is that the engine hasn’t de-rated because it has run out of AdBlue or developed a problem with the SCR system.
“It’s quite normal for the driver to tell us when we do this that the system has been disabled anyway and that the truck doesn’t use AdBlue.”
Disabling the SCR system results in a small cost saving to the operator as the truck will no longer consume AdBlue. On an older Euro 4 truck, AdBlue use will be typically four per cent or less of the fuel burn, and the litre price of the AdBlue is half or less that of pump diesel. However, it removes any element of control over NOx emissions, which are likely to become worse than those of a Euro 3 truck.
Our research revealed that there were companies offering so-called AdBlue emulators for sale over the Internet in the UK, for fitment to all makes of trucks using SCR to control NOx emissions. Most of the sites did state that the fitment of such systems would raise emissions to beyond the legal limits set for the trucks when they were new, but it’s important to note that it is not a specific offence to install such devices in the UK.
Currently, the emissions testing of in-service vehicles in the UK is slack. The annual test for diesel engine heavy vehicles is only concerned with particulate matter (smoke) emissions, and most vehicles go through with only a visual test being made.
In cases where the tester is concerned by visible smoke emissions, an opacity meter is used to check the engine conforms to legal limits, but most modern engines produce little or no visible smoke unless the engine is badly worn or there is a mechanical fault.
The water is further muddied by used trucks being prepared for export to countries where there is no AdBlue distribution network or requirement for Euro 4 or better emissions.
In some cases, manufacturers themselves are removing the systems altogether and recalibrating and certifying the engines to Euro 3 standard, but this is apparently only being done on vehicles already assigned for export outside the EU (typically to markets in Africa) and franchised dealers are forbidden from selling such vehicles back into the UK.
Transport Operator asked what, if anything, was been done to regulate the use of such devices, at a recent transport managers’ conference held by the Freight Transport Association in Chepstow. The FTA’s head of engineering, Andy Mair, said that he understood individual truck manufacturers were lobbying the Department for Transport to: “close the legal loophole that currently allowed such devices and make their use an offence under the Construction and Use regulations.”
The continuing use of these devices is likely to be contributing to degradation of air quality; and this in turn is likely to lead more local authorities to introduce measures such as low emission zones in response, placing further burdens on law-abiding operators.
Speaking at the FTA conference, the association’s climate change policy manager Rachael Dillon warned that local authorities were likely to be “increasingly aggressive” on air quality issues; and that access to HS2 sites in London and possibly elsewhere was probably going to be forbidden to all but Euro 6 trucks.
Meanwhile, the Department for Transport is understood to be investigating the use of AdBlue emulators, and also of truck engine ‘chipping’: where the vehicle’s ECU is tampered with to raise power output or improve fuel consumption. In many cases this modification will also raise emissions of NOx.
A spokesman for the Society of Motor Manufacturers & Traders told Transport Operator: “While we don’t have an official position on this, we do know that individual manufacturers have been in discussion with the DfT and we await the outcome.“
