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Life Cycle Energy and Greenhouse Gas (GHG) Emission Effects of Biodiesel in the United States with Induced Land Use Change Impacts
1/10/2018
Researchers conducted updated simulations to depict a life cycle analysis (LCA) of biodiesel production from soybeans and other feedstocks in the United States. The study addressed in detail the interaction between LCA and induced land use change (ILUC) for biodiesel. Relative to conventional petroleum diesel, soy biodiesel could achieve 76% reduction in GHG emissions without considering ILUC, or 66%-72% reduction in overall GHG emissions when various ILUC cases were considered. Soy biodiesel's fossil fuel consumption rate was also 80% lower than its petroleum counterpart. Furthermore, this study examined the cause and the implication of each key parameter affecting biodiesel LCA results using a sensitivity analysis, which identified the hot spots for fossil fuel consumption and GHG emissions of biodiesel so that future efforts can be made accordingly. Finally, researchers also investigated biodiesel produced from other feedstocks (canola oil and tallow) to contrast with soy biodiesel and petroleum diesel.
Authors: Chen, R.; Qin, Z.; Han, J.; Wang, M.; Taheripour, F.; Tyner, W.; O'Connor, D.; Duffield, J.
Notes: This Bioresource Technology article (Vol. 251 (2018): pp. 249-258) is copyrighted by Elsevier B.V. and only available by accessing it through Science Direct.
Navigation API Route Fuel Saving Opportunity Assessment on Large-Scale Real-World Travel Data for Conventional Vehicles and Hybrid Electric Vehicles: Preprint
12/22/2017
The green routing strategy instructing a vehicle to select a fuel-efficient route benefits the current transportation system with fuel-saving opportunities. This paper introduces a navigation API route fuel-saving evaluation framework for estimating fuel advantages of alternative API routes based on large-scale, real-world travel data for conventional vehicles (CVs) and hybrid electric vehicles (HEVs). The navigation APIs, such Google Directions API, integrate traffic conditions and provide feasible alternative routes for origin-destination pairs. This paper develops two link-based fuel-consumption models stratified by link-level speed, road grade, and functional class (local/non-local), one for CVs and the other for HEVs. The link-based fuel-consumption models are built by assigning travel from a large number of GPS driving traces to the links in TomTom MultiNet as the underlying road network layer and road grade data from a U.S. Geological Survey elevation data set. Fuel consumption on a link is calculated by the proposed fuel consumption model. This paper envisions two kinds of applications: 1) identifying alternate routes that save fuel, and 2) quantifying the potential fuel savings for large amounts of travel. An experiment based on a large-scale California Household Travel Survey GPS trajectory data set is conducted. The fuel consumption and savings of CVs and HEVs are investigated. At the same time, the trade-off between fuel saving and time saving for choosing different routes is also examined for both powertrains.
Authors: Zhu, L.; Holden, J.; Gonder, J.
Clean Cities Alternative Fuel Price Report, October 2017
11/29/2017
The Clean Cities Alternative Fuel Price Report for October 2017 is a quarterly report 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 October 1, 2017 and October 16, 2017, 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 2 reports that the nationwide average price (all amounts are per gallon) for regular gasoline has increased 23 cents from $2.26 to $2.49; diesel increased 29 cents from $2.47 to $2.76; CNG price increased 2 cents from $2.15 to $2.17; ethanol (E85) increased 11 cents from $1.99 to $2.10; propane decreased 6 cents from $2.84 to $2.78; and biodiesel (B20) has increased 19 cents from 2.49 to $2.68.
According to Table 3, CNG is $.32 less than gasoline on an energy-equivalent basis, while E85 is $0.24 more than gasoline on an energy-equivalent basis.
Authors: Bourbon, E.
Fuel Cell Buses in U.S. Transit Fleets: Current Status 2017
11/21/2017
This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. This annual status report combines results from all FCEB demonstrations, tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. These data and analyses help provide needed information to guide future early-stage research and development. The 2017 summary results primarily focus on the most recent year for each demonstration, from August 2016 through July 2017. The primary results presented in the report are from five demonstrations of two different fuel-cell-dominant bus designs: Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California; American Fuel Cell Bus (AFCB) Project at SunLine Transit Agency in California; AFCB Project at the University of California at Irvine; AFCB Project at Orange County Transportation Authority; and AFCB Project at Massachusetts Bay Transportation Authority.
Authors: Eudy, L.; Post, M.
What Fleets Need to Know About Alternative Fuel Vehicle Conversions, Retrofits, and Repowers
10/17/2017
Many fleet managers have opted to incorporate alternative fuels and advanced vehicles into their lineup. Original equipment manufacturers (OEMs) offer a variety of choices, and there are additional options offered by aftermarket companies. There are also a myriad of ways that existing vehicles can be modified to utilize alternative fuels and other advanced technologies. Vehicle conversions and retrofit packages, along with engine repower options, can offer an ideal way to lower vehicle operating costs. This can result in long term return on investment, in addition to helping fleet managers achieve emissions and environmental goals. This report summarizes the various factors to consider when pursuing a conversion, retrofit, or repower option.
Authors: Kelly, K.; Gonzales, J.
Biodiesel Basics
9/29/2017
This fact sheet (updated for 2017) provides a brief introduction to biodiesel, including a discussion of biodiesel blends, which blends are best for which vehicles, where to buy biodiesel, how biodiesel compares to diesel fuel in terms of performance, the difference between biodiesel and renewable diesel, how biodiesel performs in cold weather, whether biodiesel use will plug vehicle filters, how long-term biodiesel use may affect engines, biodiesel fuel standards, and whether biodiesel burns cleaner than diesel fuel. The fact sheet also dismisses the use of vegetable oil as a motor fuel.
Compressed Natural Gas Vehicle Maintenance Facility Modification Handbook
9/28/2017
To ensure the safety of personnel and facilities, vehicle maintenance facilities are required by law and by guidelines of the National Fire Protection Association (NFPA) and the International Fire Code (IFC) to exhibit certain design features. They are also required to be fitted with certain fire protection equipment and devices because of the potential for fire or explosion in the event of fuel leakage or spills. All fuels have an explosion or fire potential if specific conditions are present.
This handbook covers the primary elements that must be considered when developing a CNG vehicle maintenance facility design that will protect against the ignition of natural gas releases. It also discusses specific protocols and training needed to ensure safety.
Authors: Kelly, K.; Melendez, M.; Gonzales, J.; Lynch, L.; Boale, B.; Kohout, J.
Designing a Successful Transportation Project: Lessons Learned from the Clean Cities American Recovery and Reinvestment Act Projects
9/27/2017
The largest source of funding for alternative fuel vehicle and infrastructure projects in the U.S. Department of Energy's Clean Cities program's history came from the American Recovery and Reinvestment Act (Recovery Act). In 2009, the 25 cost-share projects totaled nearly $300 million in federal government investment. This effort included the involvement of 50 Clean Cities coalitions and their nearly 700 stakeholder partners who provided an additional $500 million in matching funds to support projects in their local communities. In total, those 25 projects established 1,380 alternative fueling stations and put more than 9,000 alternative fuel and advanced technology vehicles on the road. Together, these projects displaced 154 million gasoline gallon equivalents (GGE) of petroleum and averted 254,000 tons of greenhouse gas (GHG) emissions, while supporting U.S. energy independence and contributing to regional economic development. During post-project interviews, project leaders consistently cited a number of key components - ranging from technical and logistical factors, to administrative capabilities - for accomplishing an effective and impactful project. This report summarizes the high-level project design and administrative considerations for conducting a successful transportation project.
Authors: Kelly, K.; Singer, M.
Clean Cities Alternative Fuel Price Report, July 2017
9/5/2017
The Clean Cities Alternative Fuel Price Report for July 2017 is a quarterly report 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 July 1, 2017 and July 17, 2017, 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 2 reports that the nationwide average price (all amounts are per gallon) for regular gasoline has decreased 12 cents from $2.38 to $2.26; diesel decreased 8 cents from $2.55 to $2.47; CNG price is unchanged at $2.15; ethanol (E85) decreased 12 cents from $2.11 to $1.99; propane increased 1 cent from $2.83 to $2.84; and biodiesel (B20) is unchanged at 2.49.
According to Table 3, CNG is $.11 less than gasoline on an energy-equivalent basis, while E85 is $0.32 more than gasoline on an energy-equivalent basis.
Authors: Bourbon, E.
National Plug-In Electric Vehicle Infrastructure Analysis
9/1/2017
This document describes a study conducted by the National Renewable Energy Laboratory quantifying the charging station infrastructure required to serve the growing U.S. fleet of plug-in electric vehicles (PEVs). PEV sales, which include plug-in hybrid electric vehicles (PHEVs) and battery electric vehicles (BEVs), have surged recently. Most PEV charging occurs at home, but widespread PEV adoption will require the development of a national network of non-residential charging stations. Installation of these stations strategically would maximize the economic viability of early stations while enabling efficient network growth as the PEV market matures. This document describes what effective co-evolution of the PEV fleet and charging infrastructure might look like under a range of scenarios. To develop the roadmap, NREL analyzed PEV charging requirements along interstate corridors and within urban and rural communities. The results suggest that a few hundred corridor fast-charging stations could enable long-distance BEV travel between U.S. cities. Compared to interstate corridors, urban and rural communities are expected to have significantly larger charging infrastructure requirements. About 8,000 fast-charging stations would be required to provide a minimum level of coverage nationwide. In an expanding PEV market, the total number of non-residential charging outlets or 'plugs' required to meet demand ranges from around 100,000 to more than 1.2 million. Understanding what drives this large range in capacity requirements is critical. For example, whether consumers prefer long-range or short-range PEVs has a larger effect on plug requirements than does the total number of PEVs on the road. The relative success of PHEVs versus BEVs also has a major impact, as does the number of PHEVs that charge away from home. This study shows how important it is to understand consumer preferences and driving behaviors when planning charging networks.
Authors: Wood, E.; Rames, C.; Muratori, M.; Raghavan, S.; Melaina, M.
Sustainable Transportation Program 2016 Annual Report
8/24/2017
The efficiency and security of the transportation system affect us all - from the time and energy spent on our daily commutes to the availability of goods in our local stores. Also impacted are our pocketbooks, both as individuals and as a nation.
Transportation accounts for about 70% of national petroleum use, with Americans spending more than $177 billion to import oil in 2015. That same year, oil dependence cost the US $29 billion in lost potential GDP. Creating transportation technologies that reduce dependence on foreign oil; boost America's economy; improve national energy security; and deliver to consumers affordable, environmentally friendly choices is of critical importance.
ORNL's Sustainable Transportation Program (STP) works with government and industry to develop scientific knowledge and new technologies that accelerate the deployment of energy-efficient vehicles and intelligent, secure, and accessible transportation systems.
Scientists are tackling complex challenges in transportation using comprehensive capabilities at ORNL's National Transportation Research Center and the laboratory's signature strengths in high-performance computing, neutron sciences, materials science, and advanced manufacturing. Research focuses on electrification, efficiency of combustion and emissions, data science and automated vehicles, and materials for future systems.
Fuel Consumption Sensitivity of Conventional and Hybrid Electric Light-Duty Gasoline Vehicles to Driving Style
8/11/2017
Aggressive driving is an important topic for many reasons, one of which is higher energy used per unit distance traveled, potentially accompanied by an elevated production of greenhouse gases and other pollutants. Examining a large data set of self-reported fuel economy (FE) values revealed that the dispersion of FE values is quite large and is larger for hybrid electric vehicles (HEVs) than for conventional gasoline vehicles. This occurred despite the fact that the city and highway FE ratings for HEVs are generally much closer in value than for conventional gasoline vehicles. A study was undertaken to better understand this and better quantify the effects of aggressive driving, including reviewing past aggressive driving studies, developing and exercising a new vehicle energy model, and conducting a related experimental investigation. The vehicle energy model focused on the limitations of regenerative braking in combination with varying levels of driving-style aggressiveness to show that this could account for greater FE variation in an HEV compared to a similar conventional vehicle. A closely matched pair of gasoline-fueled sedans, one an HEV and the other having a conventional powertrain, was chosen for both modeling and chassis dynamometer experimental comparisons. Results indicate that the regenerative braking limitations could be a main contributor to the greater HEV FE variation under the range of drive cycles considered. The complete body of results gives insight into the range of fuel use penalties that results from aggressive driving and why the variation can be larger on a percent basis for an HEV compared to a similar conventional vehicle, while the absolute fuel use penalty for aggressive driving is generally larger for conventional vehicles than HEVs.
Authors: Thomas, J.; Huff, S.; West, B.; and Chambon, P.
Cow Power: A Case Study of Renewable Compressed Natural Gas as a Transportation Fuel
8/1/2017
This case study explores the production and use of R-CNG--derived from dairy farm manure--to fuel heavy-duty milk tanker trucks operating in Indiana, Michigan, Tennessee, and Kentucky. It describes the joint endeavor of Fair Oaks Farms, an Indiana-based large dairy cooperative, and ampCNG, a provider of natural gas refueling infrastructure.
Authors: Tomich, M.; Mintz, M.
Waste-to-Fuel: A Case Study of Converting Food Waste to Renewable Natural Gas as a Transportation Fuel
8/1/2017
This case study examines the production and use of R-CNG--derived from the anaerobic digestion of organic waste--to fuel heavy-duty refuse trucks and other natural gas vehicles in Sacramento, California. It highlights the joint endeavor of Atlas Disposal Industries, a waste management and recycling services company, and CleanWorld, a technology provider specializing in anaerobic digesters.
Authors: Tomich, M.; Mintz, M.
2016 Vehicle Technologies Market Report
6/23/2017
The 2016 Vehicle Technologies Market Report is the eighth edition of this report, which details the major trends in U.S. light-duty vehicle and medium/heavy truck markets as well as the underlying trends that caused them. This report is supported by the U.S. Department of Energy's (DOE) Vehicle Technologies Office (VTO), and, in accord with its mission, pays special attention to the progress of high-efficiency and alternative-fuel technologies.
Authors: Davis, S.C.; Williams, S.E.; Boundy, R.G.; Moore, S.