Current use of AFs in the freight industry
Gas-fuelled vehicles
Natural Gas (NG)
Natural gas vehicles (NGVs) are methane-powered vehicles. The methaneis derived from either fossil sources or biomethane (a raw biogas upgraded for vehicle use). According to the European Natural Gas Vehicle Association (ENGVA, 2007), in 2007 there were 6.7 million NGVs worldwide, including 820,400 in Europe (10.5 per cent of which were trucks). NGVs produce slightly lower emissions of CO2 than traditional petrol-engined cars and about the same levels of CO2 as the equivalent diesel-powered trucks. The benefit of NG is that it produces no nitrous oxides or particulate matter. Some manufacturers produce heavy goods vehicles that run purely on NG. Vehicles can be refuelled overnight at depots, which have purchased the required compressors. Dual-fuel NG diesel or NG petrol vehicles are also available.
Natural gas is still, however, fossil fuel-dependent, so does not represent a clean fuel. Methane is classed as a greenhouse gas (although the ENGVA argue that it should not be) and has a global warming potential that is 21 times that of CO2 (for an explanation of this, see Chapter 2). However, NG production from biomass actually reduces emissions of methane as it harnesses the methane normally emitted in the waste disposal process and transforms it into energy. Anaerobic digestion plants extract and process the methane from municipal waste and sewage. At present, although Sweden has plans for 80,000 biogas-powered vehicles by 2010, the UK is still in its infancy stages and has no biogas refuelling stations (Anon, 2008).
Liquid petroleum gas (LPG) and compressed natural gas (CNG)
LPG comes mostly in the form of propane and butane. LPG is a heavy gasderived from the process of petroleum refining and natural gas extraction and is stored in liquid form. In the EU, 66 per cent of LPG comes from gas field extraction and 34 per cent from crude oil refining (AEGPL, 2007). CNG is derived from similar sources but remains a gas when compressed.LPG is now a reasonably common fuel for cars and buses. As an example, 99.8 per cent of Hong Kong’s taxis and most new minibuses run on LPG. However, it does require some vehicle modifications, and although there has been an international push towards providing LPG refuelling stations, it is not yet as widely available as conventional fuels, and indeed is not yet available at all in some countries.
Environmentally, the benefits are sizeable reductions in nitrous oxidesand particulate matter at the tailpipe. However, both LPG and CNG still originate from fossil fuels, so the well-to-wheel emissions of greenhouse gases are still high. Eyre, Fergusson and Mills (2002: 53) state that LPG does not offer lifecycle carbon benefits compared with diesel and conclude that ‘LPG will have a rather marginal impact on either total road fuel energy demand or CO2 emissions and does not provide a pathway to non-fossil-fuel transport.’
Electric vehicles
Electric vehicles depend on batteries, which are still currently heavy andbulky and only enable a limited distance range to be travelled. Recent improvements in the distance range (now in excess of 250 miles), however, have led to an increase in interest in the use of this technology for vanbased homedeliveries (MacLeod, 2007) and other van-based operations. Smith Electric Vehicles, for instance, produce a range of smaller trucks (including a 9-t truck), where the batteries are stored on the underside of the truck. These are currently in use by a number of large UK companies. Although electric vehicles are not yet capable of powering larger trucks, there are many hybrid trucks on the road that combine electric and diesel power. Conventional axles can be replaced by electric-driven differential units that produce electricity to help power vehicles up hills and at the same time recharge the batteries when not in use. A growing number of vehicles also use regenerative braking systems that slow the vehicle and simultaneously recharge the battery.
For the freight industry, the attraction of electric vehicles is twofold. They are virtually pollution-free at point of use (emitting almost no tailpipe emissions), and they are much quieter than conventional goods vehicles (producing fewer vibrations). For these reasons they are eminently suitable for use within city environmental zones. On the cost front, they incur no vehicle excise duty (VED) and use no fuel (except electricity). However, the capital cost of the vehicles is considerably above that of conventional vehicles.
Electric vehicles have been in use for deliveries for decades, with the British milk-float being an early and enduring example. The technology is now fairly common in buses and considerable attention has been paid to introducing it into private cars. Academic studies have tended to focus on private transport up-take of this technology (Carlsson and Johansson- Stedmann, 2003; Delucchi and Lipman, 2001; Chan and Chan, 2001). As the pressure increases on logistics companies to become more environmentally friendly, interest in electrically powered goods vehicles looks likely to increase.
Environmentally, the benefit of electric vehicles is an almost to talelimination of both tail-pipe emissions and engine noise. The problem remains, however, that batteries must be recharged using electricity and the production of the electricity itself is environmentally unfriendly; the extent of the damage done depends on the ultimate source of the electricity. Until electricity is produced from renewable resources, the burden of environmental damage is merely being transferred from the vehicle upstream to the electricity production process.
Current use of AFs in the freight industry
As stated earlier, use of AFs in goods vehicles has received less attention than that in passenger cars. Yet, regularly fuelled and maintained in-house, fleet vehicles often run to fixed daily routes, allowing them to be switched to new technology vehicle types before public fuelling infrastructure and networks are widely available. Nevertheless, at present individual companies have to come up with their own solutions to environmental problems. Many logistics companies choose to ignore the problem completely, or rely on EURO vehicle standards to deal with it.The most proactive companies are working with vehicle manufacturers on an individual basis to come up with tailor-made solutions. Some examples of this are given below.
Tesco, Britain’s largest supermarket, owns a 25 per cent share of biofuel company, Greenenergy, which buys rapeseed from 1,500 farmers in the UK to make biodiesel. Tesco uses a 50:50 biodiesel mix in its own vehicle fleet (Tesco, 2008). This fact was once prominent on their website. By August 2008, however, there was no mention of this and indeed they are now much more circumspect, stating that ‘we recognize that the full impacts of biofuels are complex and any environmental benefit depends on how the biofuels are made,’ and ‘the full impact of biofuels is not 100 per cent clear.’ In April 2007, Tesco launched a fleet of battery-powered home delivery vans with a 100-mile range, claiming that each van saves 21 tonnes of CO2 per year (Tesco, 2008).
Sainsbury’s, another leading UK supermarket, introduced its ‘LittleGreen Van’ – an electric delivery van for making its online deliveries. By the end of 2008/09, they hope to be making a fifth of their online deliveries in these vans, carrying the advertising slogan: ‘Zero emissions – nothing comes out of this van but great food.’ Currently, Sainsbury’s (2008: 75) are less committed to the use of biofuels, stating that, although they intend to comply with the RTFO, ‘significant questions remain around the overall environmental benefits of biofuels and their impact on the developing world.’
Asda, another supermarket chain and part of the Walmart group, istrialling an electric home delivery van that has a range of 120 miles after charging for 60 minutes.
DHL, now part of Deutsche Post, which describes itself as the biggest logistics company in the world, is trialling various alternative energy vehicles around the world, including biogas, CNG, LPG and electric vehicles. Its policy on biofuels is also currently very cautionary. Its sustainability report (Deutsche Post, 2008), states:
The use of sustainable biofuels is an important option to consider, and we aredeveloping internal biofuels guidelines to help us make the right choices. Biofuels need to be carefully evaluated because their production might cause adverse social and environmental impacts – of particular concern are the possible consequences for food supplies in poor or developing countries. The public discussion on biofuels is ongoing and we are following it carefully, including through dialogue with relevant stakeholders.
Daf, one of the major truck manufacturers, prides itself on its environmental
credentials and frequently wins awards for the environmental attributes of its trucks. It is currently developing a hybrid diesel-electric medium-duty vehicle using a lithium-ion battery. Unfortunately, this example only serves to illustrate how far away the medium–heavy goods vehicle industry is from being able to effectively use alternative fuels, because this prototype vehicle is only capable of travelling 2 km using the battery, despite a battery pack weighing 100 kg (Daf, 2008). As the company’s brochure states, this is just enough for driving in and out of the green zones of city centres.
The future
It is evident from this chapter that developing new, more environmental lysustainable fuels is complex, partly because in order to make any significant inroads into the consumption of conventional fuels, the scale of production needs to be so vast that unintended and unpredictable secondary issues emerge.
In relation to biofuels, because of the land-take issues and the low efficiency of conventional biofuels, attention is turning to what are termed second-generation biofuels. These are fuels that can be made from waste materials (such as municipal waste) and cullulosic crops (dedicated energy crops) that can be grown on wasteland. According to the EU (EC, 2008: 11), use of cellolosic biomass feedstock allows new methods of biofuel production from ‘products, by-products and waste from agriculture, forestry and wood, pulp and paper with more sophisticated chemical reactions’. For instance, according to the IEA (2004), cellulosic feedstocks can be converted into ethanol using lignin (ie the non-cellulose part of the plant), and excess cellulose instead of fossil fuels can be used as the main process fuel, thus producing minimal GHG emissions. As the Royal Society (2008)argues, biofuels may form part of the solution for the future but only a small part, and other solutions will also be required. It appears that hydrogen fuel cells are not going to be the panacea that they were predicted to be. The Intergovernmental Panel on Climate Change (2007) states that by 2030 energy use and carbon emissions from transport are predicted to be 80 per cent higher than current levels. If supply-based solutions cannot be found, it seems that demand management solutions must receive even greater consideration if climate change is to be stemmed.