Biofuels – what role in the future energy mix? Facts, trends and perspectives
The use of biofuels grew strongly in Germany between 2004 and 2007, but its share has been stagnating since then, at between 5.5-6%. Biodiesel made from rape led the way, ahead of ethanol made from grain – both 1st generation biofuels. Biofuels have significant long term potential in Germany – by 2030, domestic biofuels could cover 20% of fuel needs, and a good 70% by 2050. In the EU too, biomass compliant with sustainability criteria could in the long-term cover around a third of energy needs. Globally, Brazil and the USA dominate the biofuel markets, with bioethanol as the leading product. Worldwide, residues and degraded areas alone represent a bioenergy potential of 100 to 200 exajoules, which in the long-term could cover all liquid fuel needs. The trade of bioenergy is increasing throughout the world, because the availability of and the demand for biomass, bioenergy and biofuels vary from one region to another.
The increasing use of bioenergy can give rise to competing uses. Globally, the use of agricultural biomass for feed (74%) is in the lead, followed by food (18%), and then for energy and as a material at around 4% each. The competition between fuel and food is given most attention. Biofuels can contribute to price increases and fluctuations for agricultural products; they can, however, also create employment and income. Of even greater importance for food security is the increasing demand for foodstuff. Worldwide, at the moment, 1% of agricultural land is used for modern bioenergy; in Germany the figure is 6.8% for biofuels, and 5.7% for biogas. Other competing uses arise with regard to the use of the material – for solid biomass (wood), and in the future, for bio-refineries, synthetic bio substances, and similar. Competing uses are also emerging between different sectors that use them (power, heat, transport), as well as within the transport sector. They may – at least partially – be resolved through regulation of the rights of use and exploitation. The discussion about the sustainability of biofuels has led in recent years to a large number of sustainability standards. Sustainability standards require improvements to the greenhouse gas balance for biofuels; biofuels used in Germany reduce greenhouse gases by around 50% on average. The issue of indirect land-use change (iLUC) has not yet been resolved; bioenergy carriers with a low ILUC risk are therefore to be preferred. Other, mostly less specifically governed protected natural resources include biodiversity, the soil, water and social issues. The implementation of binding sustainability standards is to be seen as progress. In order to avoid undesirable side-effects, binding sustainability standards are necessary beyond European level; these are to be extended to all bioenergy and biomass uses. Over 99% of all biofuels produced today are of the 1st generation, obtained from field crops. Biofuels of the 2nd generation are, on the other hand, obtained mainly from residues, wood and grasses. They may be hydrogenated vegetable oils, cellulosic ethanol and Fischer-Tropsch diesel; however, it has not yet been possible to develop them sufficiently ready for the market. Bio-refineries, and biofuels from algae (3rd generation) go even further. Biofuels indeed possess similar, but also different product characteristics, compared with fossil fuels. According to their chemical characteristics, biofuels can only be added to a limited extent to fossil fuels or be total substitutes for them. The 1st generation biofuels used the most as of today are usually partial substitutes that can only be added to a limited degree, or require technical adjustments to engines and vehicles. Road transport is the forerunner when it comes to biofuels; blends with up to 5% biofuel are standard throughout the world; with B7 and E10, in Germany / Europe, technical blend walls seem to be reached for the time being. Of all transport carriers, heavy-duty trucks, aircraft and ships (as long as LNG does not become successful) are those with the fewest possibilities for substituting liquid fuels; the strategic value of biofuels is the highest here – for aviation, only drop-in fuels that can be deployed seamlessly are to be considered. Ambitious climate action scenarios examined how much of the biofuels potential could be implemented and by when. According to those analyses, the sustainable bioenergy potential is sufficient to cover a significantly reduced need for liquid fuels for transport by 2050 with (2nd generation) biofuel; and this applies both to Germany and the rest of the EU. Worldwide, it has been calculated that global biofuel needs will reach 30 exajoules. In order for there to be a (bio) energy transition in the transport sector, existing, sustainable biomass potential must be used as effectively as possible. Comprehensive greenhouse-gas balances and applying the same standards for all bioenergy carriers shall improve the competitiveness of the 2nd generation. In addition, a European market introduction programme for them should be set up to run for 10 years, neutral and open to new technologies. Strategic investments must be made both in the production of 2nd generation biofuels, and in cultivating the raw materials needed. To increase the acceptance of biofuels, we need biofuels and automotive technology coordinated optimally, or drop-in fuels, as well as increased transparency with regard to the provenance of biomass and biofuels. The (bio) energy transition in the transport sector requires regular “adjustments”; course corrections are part of this.