2 Col Articles 29/7/09 16:31 Page 16
Total Page：16
File Type：pdf, Size：1020Kb
Van emissions rrr:2 col articles 29/7/09 16:31 Page 16 DDrriivveenn ttoo ddiissttrraaccttiioonn bbyy ddooddggyy ddaattaa The Department for Transport is keen to encourage van buyers to think more carefully about vehicle specification as it ponders the impact of huge recent growth in light commercial vehicle traffic. But how helpful and realistic is a new DfT database? David Wilcox investigates. hat exactly is White Van Man up to? The government highlighted by Alan McKinnon of the Logistics Research Centre at wants to know. This is why the Commission for Integrated Edinburgh’s Heriot-Watt University in his 2007 climate-change WTransport (CfIT), a government-funded advisory body, has report for the CfIT. Carbon dioxide (CO 2) emissions from vans are been asked by the Department for Transport (DfT) to quantify the on average 360g/tonne-km, reckons Professor McKinnon, impact of UK van traffic on the environment, road safety and traffic compared with 138g/tonne-km for the “average” truck. He is by no congestion. The study is being led by former Freight Transport means alone in being concerned about vans and their CO 2 Association chief executive Richard Turner. His report is due next emissions. year. According to data from the government’s National Atmospheric “There remains a real lack of knowledge about this sector,” says Emissions Inventory, vans contributed over 16 per cent of all CO 2 Mr Turner. “This study will be one of the first attempts to really get emissions from UK road transport in 2006. The European to grips with this complex area, to find out why there has been so Commission has reacted to figures like these by proposing targets much growth and to assess the impacts of any future growth in the for van CO 2 emissions of 175g/km by 2012 and 160g/km by market.” 2015 ( Transport Engineer October 2008). These are sales- The DfT’s eagerness to get up close and personal to White Van weighted average targets, to be based on a formula likely to take Man is easy to understand. UK van traffic, measured in vehicle- account of vehicle size and weight. kilometres, grew by no less than 48 per cent between 1996 and One of the latest developments in the UK is the introduction two 2007, driven by a boom in on-line shopping, including months ago of the government’s van fuel data service. At the heart supermarket home deliveries. Truck and car traffic grew by a of this is a database of new-van fuel consumption and CO 2 modest 12 per cent over the same period. emissions figures, compiled by the DfT’s Vehicle Certification Big question marks remain, however, over the number of Agency (VCA). Like cars, vans are tested on European Union urban shopping trips by car eliminated as a direct result of all these home and extra-urban rolling-road cycles, totalling 11km, to produce deliveries, and over the number of bulk stock deliveries by truck “combined” fuel-economy averages. A vehicle’s CO 2 emissions replaced by a plethora of van deliveries. figure, in g/km, is derived from its combined average fuel economy. One big disadvantage of substituting trucks with vans is “This database is good news for van buyers,” said transport 16 Transport Engineer August 2009 Van emissions rrr:2 col articles 29/7/09 16:31 Page 17 secretary Andrew Adonis at its June launch. “It gives them access to emissions and fuel DDrriivveenn ttoo consumption information that could well shape the van they choose, as well as enabling them to cut emissions and save ddiissttrraaccttiioonn bbyy money.” The Society of Motor Manufacturers and Traders (SMMT) is similarly enthusiastic. ddooddggyy ddaattaa “Van makers are all committed to providing information that will help buyers make better-informed choices, and this database provides a level playing field for easy comparison,” says SMMT chief executive Paul Everitt. “We believe that our efforts in assisting government departments compile this information will not only impact positively on tailpipe CO 2 emissions but will also help buyers select the most economical vehicle they need for Charted territory: this shows their business.” percentage change, year-on-year, of Really? The theory sounds three types of traffic on UK roads, good, but van fleet operators and measured in vehicle-kilometres. transport engineers dipping into Source (of data): DfT. this database should be prepared to be disappointed. At present, around 1,200 vans are listed, from the parsimonious Ford Fiesta 1.4-litre diesel, 1.5-tonnes-gvw panel van (67.3mpg and 110g/km of CO 2) to the immoderate Nissan Cabstar double-cab model at 3.5 tonnes gvw (22.6mpg and 332g/km). Choosing between these two extremes would be easy. But the database does not lend itself to more detailed comparisons, and relating its figures to van operation in the real world is even more challenging. Only integral panel-vans, not bare chassis-cabs, are tested, points out the VCA. This means about 25 per cent of all 3.5-tonners are excluded, though the effect at the lighter end of the You’re getting warm: vans account for one sixth market is small. This approach is understandable: bare chassis-cab of all UK road traffic carbon dioxide emissions. figures are meaningless and it would be unreasonable to demand Source: government’s 2006 National Atmospheric Emissions Inventory. figures for every permutation of chassis-cab and body. So how come Nissan Cabstar chassis-cabs make it into the database? A more obvious and general weakness is that all vehicles are vans at 114hp with various overall lengths and body heights. All tested unladen. A loading of, say, 50 per cent of maximum payload have precisely the same fuel economy and exhaust emissions, we surely would provide most van-users with more useful information. are told. Some of the data on this database look plain unbelievable. Take Confusingly, though power rating apparently makes not one jot of the LDV Maxus, for example. Of the 33 models listed, 30 have difference to Maxus mpg and CO 2 emissions, in most other cases identical mpg and emission figures. Is the VCA really telling us that power output differences are the fuel economy and exhaust emission figures of a 2.8-tonnes- reflected in fuel economy and None the wiser: “worst case” gvw, short-wheelbase 95hp Maxus are precisely the same as those exhaust-emission figures, as with figures in the VCA database means of a 3.5-tonnes-gvw, long-wheelbase, extra-high-roof model at 114, 134 and 174hp Daily vans. mpg is gloriously unaffected by 135hp? This is what the database says. It also lists 32 Iveco Daily Yet load volume is gross weight and load length. make model vehicle name fuel engine transmission load gross urban extra combined CO 2 type size length weight mpg urban mpg g/km (cc) (metres) (kg) mpg LDV Maxus 2.8t SWB SR 95PS diesel 2500 manual 2.6 2800 27.7 35.8 32.1 230 LDV Maxus 2.8t SWB SR 120PS diesel 2500 manual 2.6 2800 27.7 35.8 32.1 230 LDV Maxus 2.8t LWB XHR 95PS diesel 2500 manual 3.4 2800 27.7 35.8 32.1 230 LDV Maxus 3.2t SWB SR 95PS diesel 2500 manual 2.6 3200 27.7 35.8 32.1 230 LDV Maxus 3.2t SWB HR 120PS diesel 2500 manual 2.6 3200 27.7 35.8 32.1 230 LDV Maxus 3.2t LWB XHR 135PS diesel 2500 manual 3.4 3200 27.7 35.8 32.1 230 LDV Maxus 3.5t LWB HR 95PS diesel 2500 manual 3.4 3500 27.7 35.8 32.1 230 LDV Maxus 3.5t LWB HR 120PS diesel 2500 manual 3.4 3500 27.7 35.8 32.1 230 LDV Maxus 3.5t LWB XHR 135PS diesel 2500 manual 3.4 3500 27.7 35.8 32.1 230 August 2009 Transport Engineer 17 Van emissions rrr:2 col articles 29/7/09 16:31 Page 18 inconsequential, it seems. The unavoidable conclusion is that this case”) despite huge variations in wheelbase, roof-height and power database is vague and inconsistent, in stark contrast to the VCA’s output. Yet vehicle-makers are free to distinguish between models well-established database on car fuel economy, which clearly on the basis of power rating or gross weight, provided they pay for differentiates between even slight variations in specification, the additional testing needed to split a family of models into sub- including tyre size. And whereas CO 2 is the only exhaust emission groups. accounted for in the van database, many more are published for Applying worst-case fuel economy and exhaust emission figures cars, including particulates and NOX (oxides of nitrogen). It is the to 30 or so variants in a model range is at best unhelpful, and same story for noise levels: included in the car database but probably downright misleading. Taking no account of the effect of omitted for vans. payload volume on fuel consumption seems perverse. Allowing All in all, this much-trumpeted information source on vans looks vehicle manufacturers to determine their own published fuel like an extremely poor relation of its car cousin. The information is economy figures by choosing how their model families are sub- sparse and the failure to distinguish between critical vehicle divided and then presenting all the figures on an equal footing on a specifications is certain to frustrate van-buyers and engineers. government database intended to help van buyers is unacceptably Attributing identical fuel and consumption figures to huge numbers inconsistent.