Will all new trucks, buses and coaches soon come with energy efficiency labels? Don’t bet against it, says diesel engine technology expert, Cummins.
Given the tough limits already imposed on emissions of NOx, particulates and other pollutants by Euro-6, European legislators are unlikely to introduce a Euro-7 standard, according to Cummins’ Product Environmental Management Director, Peter Williams, but instead focus on cutting CO2 emissions. This is good news for operators given that lower CO2 output equals lower fuel usage.
One way of doing this, says Williams, is through the use of VECTO – a vehicle energy consumption calculation tool developed by the Graz University of Technology in Austria.
It contains data on the engine’s CO2 output – gathered by running the engine at fixed speed on a test bed – as well as the efficiency of the transmission and drive axle. The vehicle’s air drag and rolling resistance of the tyres fitted will also be taken into account.
“Labels that give details of rolling resistance already have to be supplied on tyres,” Williams points out.
The CO2 output of tractor units and drawbar rigids will clearly be affected by the type of trailers they pull. “A fixed design of trailer will be used to get the necessary information,” he says. While all this data could certainly be included on a label, in practice it seems more likely the vehicle concerned will be given a single CO2 rating.
“As things stand it looks as though VECTO will be introduced gradually from 2017/18 to 2022,” Williams says.
VECTO gives rise to a number of questions that have yet to be answered, not least how the data will be validated and how manufacturers will provide information on the variety of models produced.
Euro-6 remains something of a movable feast, with tighter onboard diagnostics thresholds for NOx and particulates progressively being introduced between now and 2017.
As part of Euro-6, legislators are keen to ensure the emissions standards met when a vehicle rolls off the production line continue to be adhered to while it is in service. Manufacturers, including suppliers of engines such as Cummins, are obliged to test a number of vehicles in real-world service annually under the Portable Emissions Measurement System, with the results sent to the Vehicle Certification Agency. It’s not a simple or a cheap exercise, as each one takes around a week and costs in the region of £10,000.
Acutely concerned about air quality, the European Commission is assessing whether these tests are tough enough. It is now looking, for example, at cold start emissions.
If the Commission concludes Euro-6 is proving unsuccessful in controlling emissions in service then a new Euro-7 standard might be a possibility, but isn’t under consideration at present, according to Williams.
VECTO’s arrival looks set to spur manufacturers to address ways of improving CO2 figures. Measures are likely to include Vehicle Acceleration Rate Management – restricting the ability of drivers to accelerate harshly and so burn fuel unnecessarily – the correct sizing of engines to ensure they are not too big or too thirsty for the application concerned, and the use of stop/start systems.
Offering it on a big-capacity diesel is more technically challenging than adding it to a 1.8 engine fitted to a panel van.
“We should have stop/start available for buses from March 2016 onwards; however – it could end up being used on trucks too – and we already offer it for hybrid applications,” says William Lamb, Programme Leader, Darlington Technical Operations.
Due to celebrate its 50th anniversary this year, Cummins’ Darlington, County Durham, factory employs 1,000 people and turns out 40,000 engines annually.
Cummins has a workforce of 5,000 in Britain, and lists ADL, DAF and Wrightbus among the UK manufacturers that use its diesel engines. It has recently embarked on a search for the oldest-surviving vehicles with Darlington-built engines, and the best will be invited to join the staff at a celebration day at the factory in July.
Cummins’ Bus Engine Sales Leader Ashley Watton says, “More than a million engines have been built at Darlington over the years, so we should have many to choose from.”