BIOFUEL: NOT JUST ONE PERFECT SOLUTION
Biodiesel, bioethanol and biomethane can meanwhile be produced from a multitude of plants. Besides rapeseed, grains, oil palms and sugarcane, even flora such as the Barbados nut or camelina flowering plant may be considered. The latter two offer the advantage that they will grow on relatively infertile ground, and thus do not compete with the cultivation of food crops—for this is the main complaint about biofuels at the present time.
Indeed, in 2007 and 2008, bloody riots broke out in Mexico, Haiti and Egypt, because food had become so expensive that a large percentage of the population could no longer afford to purchase the basic necessities. One of the reasons for the dramatic price hikes was high demand for raw materials for biofuel production. Compared to the onset of the millennium, the price of grain, for instance, had almost tripled by the early summer of 2008.
In addition, the climatic effects of these socalled first-generation biofuels turned out to be anything but perfect. It is admittedly true that the combustion of biofuels releases only the carbon dioxide that the plants had withdrawn earlier from the atmosphere in order to grow. Yet if the CO2 emissions that were occasioned by the harvesting, transport and processing of the crop are factored in, they lose much of their green advantages. And whenever acreage for growing these plants must be cleared first—by cutting down virgin forest, for instance—it contributes to a carbon dioxide debit that can be paid off only after several decades of biofuel production.
The calculations work out rather better when it comes to the second generation of biofuels. They differ from the first generation in that here the entire plant, including the stalk and the root and even plant waste, can be processed to yield biofuel or gas. However, work still continues in order to make the technology cost-effective. A range of hurdles, such as the breakdown of the highly resistant cellulose content of the plants, still prevents all forms of biofuel production from becoming sufficiently competitive.
“There just isn’t one perfect solution,” believes Dietmar Kemnitz of the Agency for Renewable Resources (FNR) at Germany’s Agriculture Ministry in an article in a recent MAN Newsletter. Therefore, nobody can possibly estimate yet which regenerative raw material, or which method of production, will turn out to be the most energy-efficient, cost-effective and environmentally friendly— especially because it depends on the development of engines and the supply infrastructure.
