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Analysis of the Efficiency of the U.S. Ethanol Industry 2007
3/27/2008
In 2007, the Renewable Fuels Association (RFA) conducted a survey of US ethanol production plants to provide an assessment of the current US ethanol industry. The survey covers plant operations in both corn dry mills and wet mills. In particular, it includes plant type, ownership structure, capacity, feedstocks, production volumes, coproducts,process fuel and electricity usage, water consumption, and products transportation and distribution. The survey response was based on year 2006 data. At the request of RFA, Argonne National Laboratory (ANL) has performed a statistical analysis of the survey data, as an in-kind effort, under a non-disclosure agreement (NDA) between ANL and RFA. During November 2007 and January 2008, ANL processed and analyzed the raw data for statistics. This extended technical memo serves as an official documentation to summarize ANL?s analysis.
Authors: Wu, May
Modeling Tomorrow's Biorefinery-the NREL Biochemical Pilot Plant
3/1/2008
The Biochemical Pilot Plant housed in the Alternative Fuels User Facility at NREL in Golden, Colorado, provides state-of-the-art laboratories to develop and improve the technologies that convert biomass to fuels, chemicals, and materials. The focus is on testing processes to create high-value products from cellulosic biomass.
Life-Cycle Assessment of Energy and Greenhouse Gas Effects of Soybean-Derived Biodiesel and Renewable Fuels
3/1/2008
The life-cycle energy and greenhouse gas (GHG)emission impacts of three soybean-derived fuels were studied by expanding, updating, and using Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The fuels studied included biodiesel produced from soy oil transesterification; renewable diesel produced from hydrogenation of soy oil by using two processes (renewable diesel I and II); and renewable gasoline produced from catalytic cracking of soy oil. Four allocation approaches were used to address the co-products: a displacement approach; two allocation methods, one based on energy value and one based on market value; and a hybrid approach that integrates both the displacement and allocation methods. Each of the four allocation approaches generated different results and demonstrate the importance of the methods used in dealing with co-product issues for these renewable fuels.
Authors: Huo, H.; Wang, M.; Bloyd, C.; Putsche, V.
Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land Use Change
2/7/2008
Most prior studies have found that substituting biofuels for gasoline will reduce greenhouse gases because biofuels sequester carbon through the growth of the feedstock. These analyses have failed to count the carbon emissions that occur as farmers worldwide respond to higher prices and convert forest and grassland to new cropland to replace the grain (or cropland) diverted to biofuels. By using a worldwide agricultural model to estimate emissions from land-use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products.
Authors: Searchinger, T.; Heimlich, R.; Houghton, R.; Dong, F.; Elobeid, A.; Fabiosa, J.; Tokgoz, S.; Hayes, D.; Yu, T-H.
Notes: Originally published in Science Express on 7 February 2008, Science 29 February 2008: Vol. 319. no. 5867, pp. 1238 - 1240DOI: 10.1126/science.1151861
BAE/Orion Hybrid Electric Buses at New York City Transit
1/1/2008
This report is part of a series of evaluation from the U.S. Department of Energy through the Advanced Vehicle Testing Activity (AVTA) at NREL. The role of AVTA is to bridge the gap between research and development and the commercial availability for advanced vehicle technologies that reduce petroleum use while meeting air quality standards.
DOE/NREL evaluated the original 10 prototype diesel-hybrid buses from Orion and BAE Systems operated by the New York City Transit Co. (NYCT) The next report focused on 10 new compressed natural gas (CNG) and 10 next generation diesel hybrid electric buses. In the present evaluation, the focus is on hybrid-electric transit buses (equipped with BAE Systems' HybriDrive propulsion system) purchased by NYCT in an order group of 200 (Gen II), and their performance during their first year of service.
Authors: Barnitt, R.
Virginia Biodiesel Environmental Compliance Primer
1/1/2008
Biodiesel fuel production, like other industrial processes, is subject to laws and regulations for protecting air, water, and land resources, assuring safe handling of hazardous materials, and proper disposal of wastes. Some of these requirements apply to small scale producers as well as to large commercial operations. This primer aims to acquaint the reader with the environmental regulatory obligations concerning biodiesel fuel production.
Clean Cities Alternative Fuel Price Report - January 2008
1/1/2008
The January 2008 Clean Cities Alternative Fuel Price Report is a quarterly report keeping you up to date on the prices of alternative fuels in the U.S. and their relation to gasoline and diesel prices. This issue describes prices that were gathered from Clean Cities coordinators and stakeholders between Jan. 21 and Jan. 31, 2008, and then averaged in order to determine regional price trends by fuel and variability in fuel price within regions and among regions. The prices collected for this report represent retail, at-the-pump sales prices for each fuel, including Federal and state motor fuel taxes.
Table 1 illustrates that the nationwide average price for regular gasoline has risen 23 cents to $2.99 per gallon; CNG has risen 16 cents to $1.93; and ethanol (E85) has risen 11 cents to $2.51 per gallon.
Authors: Laughlin, M.D.
Worldwide Biomass Potential: Technology Characterizations
12/30/2007
A joint EERE-PI project was completed to estimate the worldwide potential to produce and transport ethanol and other biofuels, with an emphasis on the 5 year and 10 year potential for biofuels supply to the United States. The project included four specific tasks: 1) identify the range of countries to be included in the study, 2) assess the resource potential for production of ethanol from sugar and starch-based feedstocks, and biodiesel, 3) assess the resource potential for production of other biofuels, including lignocellulosic ethanol, pyrolysis oil, and renewable diesel, and 4) integrate results into the MARKAL energy policy model. The project team included DOE (Policy and International and the Office of the Biomass Program), Oak Ridge National Laboratory (feedstock supply curves), the National Renewable Energy Laboratory (conversion technology characterizations), and Brookhaven National Laboratory (MARKAL analysis).
The NREL portion of this study was primarily concerned with estimating the plant gate price (PGP) of liquid biofuels (corn and wheat dry mill ethanol, cellulosic ethanol, biodiesel, renewable diesel, and pyrolytic fuel oil) from selected biomass feedstocks for countries included in the study using representative existing and developing technologies. A methodology for comparing costs between countries was developed. Plant sizes studies ranged from 25 MM GPY to 100 MM GPY. The results of the technology characterizations (capital costs, operating costs, plant gate prices) are presented in 2005 U.S. dollars and include estimates of comparative costs in each country.
Authors: Bain, Richard L.
Energy Independence and Security Act of 2007
12/19/2007
The Energy Independence and Security Act (EISA) of 2007 put into law many of the provisions of Executive Order 13423. The goal of the EISA law is to move the United States toward greater energy independence and security, to increase production of clean renewable fuels, to protect consumers, to increase the efficiency of products, buildings, and vehicles, to promote research on and deploy greenhouse gas capture and storage options, and to improve the energy performance of the Federal Government.
On-Road Evaluation of Advanced Hybrid Electric Vehicles over a Wide Range of Ambient Temperatures
12/1/2007
Hybrid electric vehicles can provide increased fuel economy over convention gasoline powered vehicles but these advantages can be affected dramatically by wide variations in operating temperatures. To investigate cold and hot temperature effects on HEV operation and efficiency, an on-road evaluation protocol was defined and conducted over a 6-month study at widely varying temperatures ranging from -14 degrees C to 31 degrees C.
Authors: Carlson, R.; Duoba, M.; Bocci, D.; Lohse-Busch, H.
Impact of Component Size on Plug-In Hybrid Vehicle Energy Consumption Using Global Optimization
12/1/2007
Plug-in hybrid electric vehicles are a promising alternative to gas-only vehicles and offer the potential to greatly reduce fuel use in transportation. Their potential energy consumption is highly linked to the size of the components. This study focuses on the impact of the electric system energy and power on control and energy consumption. Based on a parallel pre-transmission architecture, several vehicles were modeled with an all-electric range from 5 to 40 miles on the Urban Dynamometer Driving Schedule to illustrate various levels of available electric energy. Five other vehicles were created, with various levels of power and the same battery energy. The vehicles were then simulated under optimal control on multiple combinations of cycle and distance by using a global optimization algorithm. The results from each optimization were analyzed to highlight control patterns. The potential minimal fuel consumption that can be achieved by each of them is presented in this report.
Authors: Karbowski, D.; Haliburton, C.; Rousseau, A.
Plug-In Hybrid Electric Vehicles: How Does One Determine Their Potential for Reducing U.S. Oil Dependence?
12/1/2007
Estimation of the potential of plug-in hybrid electric vehicles' (PHEVs') ability to reduce U.S. gasoline use is difficult and complex. Although techniques have been proposed to estimate the vehicle kilometers of travel (VKT) that can be electrieid, these methods may be inadequate and/or inappropriate for early market introduction estimates. Factors that must be considered with respect to the PHEV itself include (1) kWh battery storage capability; (2) kWh/km depletion rate of the vehicle; (3) liters/km use of gasoline; (4) average daily kilometers diven; (5) annual share of trips exceeding the battery depletion distance; (6) driving cycle(s); (7) charger location; (8)charging rate. Taking into account PHEV design trade-off possibilities (kW vs. kWh of battery, in particular), this paper attempts to extract useful information relating to these topices. Costs per kWh of PHEVs capable of charge depleting (CD) all-electric range vs. those CD in "blended mode (CDB) are examined. Lifetime fuel savings of alternative PHEV operating/utilization strategies are compared to battery cost estimates.
Authors: Vyas, A.; Santini, D.; Duoba, M.; Alexander, M.
Life-Cycle Assessment of Corn-Based Butanol as a Potential Transportation Fuel
11/1/2007
Butanol produced from bio-sources (such as corn) could have attractive properties as a transportation fuel. Production of butanol through a fermentation process called acetone-butanol-ethanol (ABE) has been the focus of increasing research and development efforts. The purpose of this study is to estimate the potential life-cycle energy and emission effects associated with using bio-butanol as a transportation fuel. The study employs a well-to-wheels analysis tool named the Greenhouse Gases, Regulated Emissions and Energy Use in Transportation (GREET) model developed by Argonne National Laboratory and the Aspen Plus model developed by AspenTech. The study describes the butanol production from corn, including grain processing, fermentation, gas stripping, distillation, and adsorption for products separation. Our study shows that, while the use of corn-based butanol achieves energy benefits and reduces greenhouse gas emissions, the results are affected by the methods used to treat the acetone that is co-produced in butanol plants.
Authors: Wu, M.; Wang, M.; Liu, J.; Huo, H.
Biofuels: An Important Part of a Low-Carbon Diet
11/1/2007
New rules are being developed that will require fuel providers to account for and reduce the heat-trapping emissions associated with the production and use of transportation fuels. The purpose of this report is to ensure that we "count carbs" accurately, by explaining why we need a comprehensive accounting system for carbon emissions--one that measures global warming emissions over a transportation fuel's entire life cycle. We also need to "make carbs count" by creating performance-based policies that will reward low-carbon transportation fuels for their performance.
