are lower, more particulate matter is emitted and, as a consequence, particulate filters must be installed to reduce PM10 emissions to the regulated levels. Such filters are not required by SCR systems. The future development of truck exhausts will partly depend therefore on the evolution of EGR and SCR systems, independently or in combination.
Other non-fuel-related improvements to the environmental performance of trucks are likely to be incremental. For example, the combination of quieter engines, air brake silencers, internal load restraint systems, low rolling resistance tyres, quieter refrigeration units and cab sound-proofing offers the potential for further noise reduction.
Vans
Carrying capacity
Unlike trucks, the maximum permissible weight of vans does not change over time as a result of governments relaxing restrictions on vehicle weights. Instead the weight limit for vans (also referred to as light goods vehicles, or light commercial vehicles) is fixed, as it defines whether the vehicle is a van or truck, and thereby the regulations that the vehicle and its owner and driver are subject to. In many countries the maximum permissible gross weight for vans is 3.5 tonnes (it is important to note that some vehicles are manufactured with van bodies with a gross weight of over 3.5 tonnes but these vehicles are treated as trucks in terms of driving and operational regulations).
Vehicle manufacturers produce a wide range of styles, weights and sizes of vans. These can be categorized by gross weight as small (car-derived/micro), medium and heavy vans. Table 7.1 provides a summary of the typical attributes of these three categories of van.
Vans have a far wider range of uses than trucks. In fact, only around one van trip in five actually carries freight. Survey work in Britain suggested that in the period 2002–03 commuting accounted for 39 per cent of all van journeys, servicing for 23 per cent, goods collection and delivery for 22 per cent, and personal journeys for 16 per cent (Allen and Browne, 2008).
This wide range of journey purposes means that van operators have extremely varying requirements in terms of load space, payload, vehicle length, vehicle height and vehicle body requirements, and put the load area of the vehicle to differing uses. For example, in the case of service activities often only tools, equipment and parts are transported (which may not be particularly heavy) and vans may be equipped with sophis-ticated racking systems for these purposes. In some operations drivers
will require space to work inside the vehicle (for example, an electrician having to carry out preparatory work inside the vehicle, or a delivery driver sorting goods in a parcel delivery operation). As a result, the average lading factor (in terms of weight and volume) for the van popu-lation is likely to be lower than for trucks. In Britain, the Company Van Survey that was conducted between 2003–2005 showed that, overall, vans were more than half full (by volume) for only 34 per cent of total vehicle kilometres travelled (DfT, 2008a).
Even though vans have a maximum gross weight of 3.5 tonnes, the average gross weight and payload of vans can increase if operators purchase a greater proportion of heavier vans over time. This has been happening in the van sector. Analysis of the vans sold in Britain between 1990 and 2007 suggests that the average gross weight and payload of vans has increased by 10–20 per cent over this period.1
Regulations have not prevented manufacturers from increasing the length of vans. A growing proportion of the medium and heavy vans are being produced with long wheel bases (the wheel base is the distance between the front and rear wheels). The longer the wheel base, the bigger the load space in the vehicle. Vans with long wheel bases are often between ½–1½ metres longer than their medium wheel base equivalents.
Assuming that the width and height of these vehicles are the same, the Table 7.1 Summary of the typical size, weight and fuel efficiency attributes of vans
small vans medium vans heavy vans Typical gross weight
(tonnes) Up to 1.8 1.8–2.6 2.6–3.5
Typical payload
(tonnes) 0.4–0.8 0.8–1.2 1.2–2.0
Typical load space (m3)
1–3 4–8 7–17
Typical fuel consumption (mpg)
(Litres per 100 km) 40–55
(7.1–5.1) 30–40
(9.4–7.1) 20–35
(14.1–8.1) Example models Vauxhall Corsa
Citroen Berlingo Renault Kangoo
Ford Transit VW Transporter
Renault Trafic
Ford Transit Mercedes Sprinter
Iveco Daily Source: Author’s own estimates.
long wheel base varieties have approximately an additional 20 per cent load space for every extra ½ metre of length compared with shorter vans, with little or no difference in gross weight.2
As with trucks, van manufacturers try to use lighter materials (for the chassis, body and internal racking systems) where possible to reduce the tare weight of the vehicle and hence maximize payload.
energy efficiency
Up until the 1990s the majority of vans in Europe were powered by petrol.
However, diesel engines became increasingly popular among van oper-ators as manufacturers overcame the problems of vehicle speed and noise associated with early diesel vans. In addition, diesel engines have greater fuel efficiency, are hardwearing and, due to technological advances such as fuel injection and turbo-charging, can now produce much greater power and torque (Momenta, 2006). It is estimated that diesel vehicles have a fuel economy advantage of approximately 20 to 40 per cent over petrol vehicles (EIA, 2009). In Britain, for example, 69 per cent of all vans were diesel-powered in 1998, but by 2007 this had risen to 92 per cent (DfT, 2008b). By contrast, in America diesel-powered vans have accounted for, on average, only about 4 per cent of new van sales each year for the past 20 years (EIA, 2009). The greater penetration of diesel vans in Europe is likely to be due to factors such as higher average fuel prices, more favourable tax policies for diesel, and less stringent emissions standards (which permit higher levels of NOx and PM in Europe than in America) (EIA, 2009).
As concern grows about fossil fuel consumption and emissions, leading to new regulations and tax regimes, it is likely that greater use will be made of new technologies that help to improve the fuel efficiency of vans such as hybrid vehicles, devices to reduce engine idling, and speed limiters (all of which are described in relation to trucks in the section on
‘Energy efficiency’). Hybrid vehicles and anti-idling technologies have particular relevance to vans due to the high proportion of operations carried out in urban areas, involving stop–start traffic conditions and, in some cases, multi-drop delivery rounds.
It is also likely that further significant improvements in the fuel effi-ciency of diesel engines are possible through advanced turbo-charged engines with direct injection technologies. A senior director of a major van manufacturer was recently quoted as saying that they expected ‘that small, highly efficient diesels capable of 100 miles per gallon will become commonplace’ (Anon, 2008a).
A sizeable number of vans make use of auxiliary equipment including refrigeration, air conditioning, heating, pumps, fans and power steering.
As with trucks, the use of power sources other than the vehicle engine to fuel this equipment has the potential to reduce total fossil fuel consumption.
Aerodynamic profiling is generally less important for vans than trucks owing to their smaller sizes and because a greater proportion of van activity takes place in urban areas at lower average speeds. It has, never-theless, been improving, as demonstrated by the streamlining of the Ford Transit van (Storey and Boyes, 2003).