Second-generation biofuels
The technologies to produce fuels from waste from agriculture and forestry, or specific plants with high cellulose content are still a few years away from competitive commercialization. The industry assumes that second-generation biofuels will not be available in signifi cant commercial quantities for fi ve to 10
years. The advantages put forward are high energy effi ciency, and the use of plants that grow on degraded land or in areas less important for biodiversity.
How effi cient are biofuels in reducing GHGs?
In order to utilize the full potential of biofuels for reducing GHG emissions it is crucial that the total of emissions created during their production are both as low as possible and below that of their fossil alternative. There are many elements that can lead to higher greenhouse gas emissions from biofuels than in the optimal case: GHG emissions are mainly due to fossil fuel inputs into cultivation and downstream processing. But the final result also depends on the type of crops and finally the efficiency of the engine running on it. The International Energy Agency says about 15–25 per cent reduction in GHG emissions compared to fossil fuels can be achieved by using starch based crops, for example corn in the United States, but a 90 per cent reduction with sugarcane as feedstock as grown in Brasil. In some cases the climate balance of biofuels is even negative. Nitrous oxide emissions from fertilizer application during the cultivation of the plants partially reduces CO2 emissions savings.
The controversy
Although growing fuel in fi elds sounds highly promising for solving our energy and climate problems, there are a number of controversial issues around biofuel production.
Energy versus Food: Sceptics are concerned that where biofuels are grown, no food will be harvested, and some even call for a moratorium. In a world where 850 million are considered undernourished any potential threat to aggravate this situation requires thorough and critical examination. Over the past three years, global food prices have risen 83 per cent. Governmental subsidies and targets for biofuel in developed countries has created a sudden
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