| Popis: |
The production of various types of biofuel greatly depends on the choice of feedstock and the implementation of technological options. Analysis of the biomass supply chain for a biofuel allows evaluation of the cumulative environmental impacts that result, such as the impacts of feedstock production (land use changes, manufacturing fertilizers) and fuel (production, distribution, storage), as well as the accessibility of resources to be used. The main problems in sustainability of first-generation (1G) biofuels are their impact on the food supply, competition for land and water, physical availability, and access and trade of biomass associated with increased food and feed prices (the debate of food versus fuel). The UK Royal Academy of Engineering and 178 Netherlands scientists declared that some biofuels, such as diesel produced from food crops, have caused more emissions than those produced by fossil fuels. Our investigation shows that fertilizer production creates greenhouse gas (GHG) emissions of 0.9–1.2 kg CO2e/l biodiesel. The use of fertilizers causes additional emissions that exceed the emission from their production by 2- to 5.5 fold. Thus, the production and use of fertilizers for cultivation of biodiesel feedstocks generate much greater GHG emissions compared with the rate of mitigation based on the use of biodiesel. To address these challenges, biofuel producers must shift to the use of feedstock originating from an organic agriculture approach and to the use of microalgae. |
