Western Kentucky University Research Foundation Biodiesel Project [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 2013.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- 1.32 MB : digital, PDF file
- Additional Creators:
- Western Kentucky University, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- Petroleum-based liquid hydrocarbons is exclusively major energy source in the transportation sector. Thus, it is the major CO₂ source which is the associated with greenhouse effect. In the United States alone, petroleum consumption in the transportation sector approaches 13.8 million barrels per day (Mbbl/d). It is corresponding to a release of 0.53 gigatons of carbon per year (GtC/yr), which accounts for approximate 7.6 % of the current global release of CO₂ from all of the fossil fuel usage (7 GtC/yr). For the long term, the conventional petroleum production is predicted to peak in as little as the next 10 years to as high as the next 50 years. Negative environmental consequences, the frequently roaring petroleum prices, increasing petroleum utilization and concerns about competitive supplies of petroleum have driven dramatic interest in producing alternative transportation fuels, such as electricity-based, hydrogen-based and bio-based transportation alternative fuels. Use of either of electricity-based or hydrogen-based alternative energy in the transportation sector is currently laden with technical and economical challenges. The current energy density of commercial batteries is 175 Wh/kg of battery. At a storage pressure of 680 atm, the lower heating value (LHV) of H₂ is 1.32 kWh/liter. In contrast, the corresponding energy density for gasoline can reach as high as 8.88 kWh/liter. Furthermore, the convenience of using a liquid hydrocarbon fuel through the existing infrastructures is a big deterrent to replacement by both batteries and hydrogen. Biomass-derived ethanol and bio-diesel (biofuels) can be two promising and predominant U.S. alternative transportation fuels. Both their energy densities and physical properties are comparable to their relatives of petroleum-based gasoline and diesel, however, biofuels are significantly environmental-benign. Ethanol can be made from the sugar-based or starch-based biomass materials, which is easily fermented to create ethanol. In the United States almost all starch ethanol is mainly manufactured from corn grains. The technology for manufacturing corn ethanol can be considered mature as of the late 1980s. In 2005, 14.3 % of the U.S. corn harvest was processed to produce 1.48 x10¹° liters of ethanol, energetically equivalent to 1.72 % of U.S. gasoline usage. Soybean oil is extracted from 1.5 % of the U.S. soybean harvest to produce 2.56 x 10⁸ liters of bio-diesel, which was 0.09 % of U.S. diesel usage. However, reaching maximum rates of bio-fuel supply from corn and soybeans is unlikely because these crops are presently major contributors to human food supplies through livestock feed and direct consumption. Moreover, there currently arguments on that the conversion of many types of many natural landscapes to grow corn for feedstock is likely to create substantial carbon emissions that will exacerbate globe warming. On the other hand, there is a large underutilized resource of cellulose biomass from trees, grasses, and nonedible parts of crops that could serve as a feedstock. One of the potentially significant new bio-fuels is so called "cellulosic ethanol", which is dependent on break-down by microbes or enzymes. Because of technological limitations (the wider variety of molecular structures in cellulose and hemicellulose requires a wider variety of microorganisms to break them down) and other cost hurdles (such as lower kinetics), cellulosic ethanol can currently remain in lab scales. Considering farm yields, commodity and fuel prices, farm energy and agrichemical inputs, production plant efficiencies, byproduct production, greenhouse gas (GHG) emissions, and other environmental effects, a life-cycle evaluation of competitive indicated that corn ethanol yields 25 % more energy than the energy invested in its production, whereas soybean bio-diesel yields 93 % more. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12 % by the production and combustio...
- Report Numbers:
- E 1.99:1086991
- Published through SciTech Connect.
Pan, Wei-Ping; Cao, Yan.
- Type of Report and Period Covered Note:
- Final; 07/01/2010 - 12/31/2012
- Funding Information:
View MARC record | catkey: 14987523