Using a higher degree of the biomass feedstock and by upholding the biochemical structure eventually lead to significantly higher CO2 emissions savings than the above-mentioned single product concepts. All plant-based biomass are composed of the same basic biochemical components as mentioned in Section 12.2.1 with only the concentration and yield quantity being different. In the single product system, biomass crops associated with a particularly high quantity or concentration of the desired component for conversion are selected. For example, corn is cultivated for starch and oil palm is cultivated for fatty acids. Typically the rest of the plant is combusted for thermal energy or used as low- value by - products. In the case of starch, more than 50% of the plant material and for the oil palm over 70% is not used as a main product. As any LCA will indicate, the industrial cultivation of biomass is highly energy intensive and not carbon neutral and could also come with a land use change carbon debt (see Section 12.5.2- . The direct and indirect CO2 emissions are weighted against the quantity of contributing products produced via the different biomass feedstock streams. The lower the amount of products produced, the higher the associated cultivation costs. As an explanatory guide, the starch contained in corn comprises of only 20-25% dry weight of the entire biomass material. This means that by focusing solely on bioethanol as the renewable product, the agricultural input energy of 2.5-5.0 GJ ton-1 becomes 1030 GJ ton-1 in relation to the final product, should the by-products not contribute to a CO2 saving system [25, 31]. Merely the acquisition of starch from corn thereby places a heavy burden on the overall energy balance of bioethanol. Using a higher portion of the biomass for the conversion to useable products will lower the associ ate agricultural cost and thereby contribute to a further reduction in CO2; whereby even thermal combustion can partially contribute.
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Your Alternative Fuel Solution for Saving Money, Reducing Oil Dependency, and Helping the Planet. Ethanol is an alternative to gasoline. The use of ethanol has been demonstrated to reduce greenhouse emissions slightly as compared to gasoline. Through this ebook, you are going to learn what you will need to know why choosing an alternative fuel may benefit you and your future.