Returning to the central consideration of bioenergy, it would be wrong to dis-cuss this topic without at least some passing reference to biodiesel, even though, since it revolves around a chemical refining process, it is not strictly produced by biotechnology. Like the increasing number of mineral oil substitutes currently available or under development, biodiesel is derived from vegetable oils. Modern diesel engines demand a clean-burning fuel of uniform quality which can function under all expected operating conditions. One of the main advantages of biodiesel is that it can be used directly, in unmodified engines, with the additional bonus that it can perform as a single, pure fuel, or as part of a mix with its traditional counterpart, in any ratio desired. While there remains some disagreement as to the scale of the environmental benefits to be gained, especially in respect of carbon dioxide discharges, there is good evidence that particulate emissions are signifi-cantly reduced. In addition, biodiesel is claimed to have better lubricant propertiesand to improve the biodegradability of the conventional diesel component of a blended fuel. Various studies have concluded that biodiesel exhaust is generally less harmful to both human health and the planet. Specifically, it contains sig-nificantly lower levels of polycyclic aromatic hydrocarbons (PAHs) and nitrited polycyclic aromatic hydrocarbons (nPAHs), which is of great importance, since both groups have been identified as potential carcinogens. In laboratory tests, PAHs were reduced by between 75 – 85 % (excepting benzo(a)anthracene for which the figure was around 50%) and nPAHs were also dramatically lessened. Most of the targeted nPAH compounds were present only as traces, while the highest levels reported, 2-nitrofluorene and 1-nitropyrene, were found to repre-sent a 90% reduction over typical conventional diesel releases. Objective views of the performance of a ‘new’ fuel depend on such information and the National Biodiesel Board was congratulated by representatives of the House Energy and Power subcommittee for being the first industry to complete the rigorous health effects testing of the Clean Air Act.
It is not entirely without irony that in 1894, when Rudolf Diesel invented the engine which bears his name, he produced a design specifically suitable for a range of fuels, including coal dust and vegetable oil, as well as the petroleum product which is automatically associated with the device. In many respects, the current resurgence of interest in the potential of a fuel source so deeply rooted in diesel’s origins might almost be described as a retrograde step in the right direction.
As stated at the outset, biodiesel is a product derived by the application of chemistry to material of biological origin and is not, thus, biotechnological in the truest sense. It does, however, illustrate very well the influence of local modality as one of the recurrent themes of the sector. For a time, use of biodiesel in the USA was confined to certain niche markets, principally because relatively low conventional fuel prices and the contemporarily high cost of vegetable oil made wider uptake unattractive. However, the impact of the legislative requirement for alternative fuel in the Energy Policy Act of 1992 (EPACT) has led to a major upsurge in usage, especially amongst bus operators and hauliers, for whom it is the most cost-effective option available.
In Europe, by contrast, the economic and environmental benefits may be less clear cut. The UK’s Royal Commission on Environmental Pollution’s major report, Energy and the Changing Climate, published in June 2000, largely ignored biodiesel, concentrating its attention more on farmed energy crops for use in combined heat and power stations. Of biomass crops for vehicle fuel, it was much less enthusiastic. Its examination of European Union funded research on oilseed rape as a raw material for biodiesel led it to identify quality control issues and conclude that the actual production of biodiesel is polluting, and is ineffi-cient in terms of both energy and cost. The economics aspect is a major one.
According to official figures from the Department for the Environment, Food and Rural Affairs (DEFRA), in 2001, UK rape seed sells for 15% less than it costs to produce, even after taking government subsidies into account (Cur-ran 2001). February 2001, eight months after the Royal Commission’s report, saw the European Commission publish the first review of its 1997 strategy for renewables, entitled The Communication on the Community Strategy and ActionPlan on Renewable Energy Sources. In this document, the poor adoption of liq-uid biofuels like biodiesel, was specifically criticised, with only Austria, France, Germany and Italy having defined policies on usage. Even so, their combined contribution to the total diesel fuelled transport sector only amounted to 0.3% in 1998, the latest period for which figures were available. As is so often the case, the report concluded that revised taxation to favour biofuels will be the key to future expansion, coupled with the establishment of specific objectives and greater incentives for the growing of energy crops under the common agricul-tural policy. These were largely adopted by November of the same year, when biofuels were prioritised in the EU as part of a strategy to reduce petroleum product dependency for transport. At the present rate, burgeoning European oil imports are predicted to increase to 90% by 2030, if no steps are taken. The first phase of a planned 20% substitution by 2020 will involve legislative and fiscal promotion of these fuels, which are to account for 2% of all fuel sold by 2004.
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