Examining the Impacts of Methane Leakage on Life-Cycle Greenhouse Gas Emissions of Shale and Conventional Natural Gas
6/1/2012
The development of large-scale shale gas production has been described as a game-changer for the U.S. energy market and has generated interest in expanding the usage of natural gas (NG) in sectors such as electricity generation and transportation. This development has been made possible by improvements in drilling technologies, specifically utilizing hydraulic fracturing in conjunction with horizontal drilling. However, the environmental implications of NG production and its use have been called into question. One of the major concerns is the amount methane (CH4) leakage from production activities and its impact on the life-cycle greenhouse gas (GHG) emissions of NG.
Authors: Burnham, A.; Clark, C.
Notes: This article appears in the June 2012 issue of EM Magazine, a publication of the Air & Waste Management Association (A&WMA; www.awma.org). To obtain copies and reprints, please contact A&WMA directly at 1-412-232-3444.
Converting Vehicles to Propane Autogas - Part 2: Installing Underhood Components
6/1/2012
This document is Part 2 of a four-part series of courses developed by the Propane Education & Research Council on retrofitting, servicing and fueling highway vehicles that run on propane autogas. The Part 2 course covers the installation of underhood fuel-system components.
Notes: This publication is copyrighted by Propane Education and Research Council.
Clean Cities Alternative Fuel Price Report, April 2012
5/1/2012
The Clean Cities Alternative Fuel Price Report for April 2012 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 March 30, 2012 and April 13, 2012, 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 reports that the nationwide average price for regular gasoline has risen 52 cents per gallon from $3.37 per gallon to $3.89 per gallon; diesel has risen 26 cents per gallon from $3.86 to $4.12; CNG price has dropped 5 cents from $2.13 to $2.08; ethanol (E85) has risen 33 cents from $3.14 to $3.47 per gallon; propane has dropped 17 cents from $3.08 to $2.91; and biodiesel (B20) has risen 23 cents from $3.95 to $4.18 per gallon.
According to Table 2, CNG is about $1.81 less than gasoline on an energy-equivalent basis, while E85 is about $1.01 more than gasoline on an energy-equivalent basis.
Authors: Babcock, S.
Analyzing Vehicle Fuel Saving Opportunities through Intelligent Driver Feedback
4/16/2012
Driving style changes, e.g., improving driver efficiency and motivating driver behavior changes, could deliver significant petroleum savings. This project examines eliminating stop-and-go driving and unnecessary idling, and also adjusting acceleration rates and cruising speeds to ideal levels to quantify fuel savings. Such extreme adjustments can result in dramatic fuel savings of over 30%, but would in reality only be achievable through automated control of vehicles and traffic flow. In real-world driving, efficient driving behaviors could reduce fuel use by 20% on aggressively driven cycles and by 5-10% on more moderately driven trips. A literature survey was conducted of driver behavior influences, and pertinent factors from on-road experiments with different driving styles were observed. This effort highlighted important driver influences such as surrounding vehicle behavior, anxiety over trying to get somewhere quickly, and the power/torque available from the vehicle. Existing feedback approaches often deliver efficiency information and instruction. Three recommendations for maximizing fuel savings from potential drive cycle improvement are: 1) leveraging applications with enhanced incentives, 2) using an approach that is easy and widely deployable to motivate drivers, and 3) utilizing connected vehicle and automation technologies to achieve large and widespread efficiency improvements.
Authors: Gonder, J.; Earleywine, M.; and Sparks, W.
Notes: Posted with permission. Presented at the 2012 SAE World Congress and Exhibition, April 24-26, 2012, Detroit, Michigan.
E15 Misfueling Mitigation Plan
3/2/2012
The purpose of this Misfueling Mitigation Plan (MMP) is to set forth how the plan submitter will comply with the misfueling mitigation conditions established by the U.S. Environmental Protection Agency (EPA or the Agency) in its October 13, 2010, and January 21, 2011, partial waivers allowing fuel and fuel additive manufacturers to introduce into U.S. commerce ethanol blends containing greater than 10 volume percent and no more than 15 volume percent ethanol (E15) for use in model year 2001 and newer light duty motor vehicles. The MMP, which is intended to reduce the potential of E15 being used in all engines, vehicles and equipment for which waivers have not been granted by the Agency, addresses the following required elements: E15 pump labeling, tracking of E15 through the supply chain through product transfer documentation, and implementation surveys of E15 content and labeling compliance.
Because this plan has been developed as a model plan, a company that wishes to use it must notify EPA in writing that the company seeks approval of the plan for the company's use in meeting the requirements for an MMP. Before deciding whether to approve a plan, EPA may seek additional information and/or misfueling mitigation measures as appropriate in view of the company's circumstances. EPA must approve a company's submission of this MMP before the company may use it to demonstrate its compliance with the partial waiver conditions.
Notes: This copyrighted publication is posted on the U.S. Department of Energy, Energy Efficiency & Renewable Energy website Alternative Fuels Data Center with permission from Renewable Fuels Association, Washington, D.C.
Thirty-Six Month Evaluation of UPS Diesel Hybrid Electric Delivery Vans
3/1/2012
This 36-month follow-up evaluation is part of a series of evaluations by the U.S. Department of Energy (DOE). Using an established and documented evaluation protocol, DOE - through the National Renewable Energy Laboratory (NREL)- has been tracking and evaluating new propulsion systems in transit buses and trucks for more than 10 years. The DOE/NREL vehicle evaluations are a part of the Advanced Vehicle Testing Activity (AVTA), which supports DOE's Vehicle Technologies Program.
This report focuses on a parallel hybrid-electric diesel delivery van propulsion system currently being operated by United Parcel Service (UPS). The hybrid propulsion system is an alternative to the standard diesel system and allows for increased fuel economy, which ultimately reduces petroleum use.
Authors: Lammert, M., Walkowicz, K.
Clean Cities 2012 Vehicle Buyer's Guide
3/1/2012
The expanding availability of alternative fuels and advanced vehicles makes it easier than ever to reduce petroleum use, cut emissions, and save on fuel costs. The Clean Cities 2012 Vehicle Buyer's Guide features a comprehensive list of model year 2012 vehicles that can run on ethanol, biodiesel, electricity, propane or natural gas.
Renewable Fuels and Lubricants (ReFUEL) Laboratory
3/1/2012
This fact sheet describes the Renewable Fuels and Lubricants (ReFUEL) Laboratory at the U.S. Department of Energy National Renewable Energy Laboratory (NREL) is a state-of-the-art research and testing facility for advanced fuels and vehicles. Research and development aims to improve vehicle efficiency and overcome barriers to the increased use of renewable diesel and other nonpetroleum-based fuels, such as biodiesel and synthetic diesel derived from biomass. The ReFUEL Laboratory features a chassis dynamometer for vehicle performance and emissions research, two engine dynamometer test cells for advanced fuels research, and precise emissions analysis equipment. As a complement to these capabilities, detailed studies of fuel properties, with a focus on ignition quality, are performed at NREL's Fuel Chemistry Laboratory.
Clean Cities Alternative Fuel Price Report, January 2012
2/1/2012
The Clean Cities Alternative Fuel Price Report for January 2012 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 January 13, 2012 and January 27, 2012, 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 reports that the nationwide average price for regular gasoline has dropped 9 cents per gallon from $3.46 per gallon to $3.37 per gallon; diesel has risen 5 cents per gallon from $3.81 to $3.86; CNG price has risen 4 cents from $2.09 to $2.13; ethanol (E85) has dropped 5 cents from $3.19 to $3.14 per gallon; propane has risen 2 cents from $3.06 to $3.08; and biodiesel (B20) has risen 4 cents from $3.91 to $3.95 per gallon.
According to Table 2, CNG is about $1.24 less than gasoline on an energy-equivalent basis, while E85 is about $1.07 more than gasoline on an energy-equivalent basis.
Authors: Babcock, S.
Life-Cycle Analysis of Shale Gas and Natural Gas
12/1/2011
The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. Using the current state of knowledge of the recovery, processing, and distribution of shale gas and conventional natural gas, we have estimated up-to-date, life-cycle greenhouse gas emissions. In addition, we have developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps - such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings - that need to be addressed further. Our base case results show that shale gas life-cycle emissions are 6% lower than those of conventional natural gas. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty regarding whether shale gas emissions are indeed lower than conventional gas emissions. This life-cycle analysis provides insight into the critical stages in the natural gas industry where emissions occur and where opportunities exist to reduce the greenhouse gas footprint of natural gas.
Authors: Clark, C.E.; Han, J.; Burnham, A.; Dunn, J.B.; Wang, M.
Life-Cycle Greenhouse Gas Emissions of Shale Gas, Natural Gas, Coal, and Petroleum
11/22/2011
The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. It has been debated whether the fugitive methane emissions during natural gas production and transmission outweigh the lower carbon dioxide emissions during combustion when compared to coal and petroleum. Using the current state of knowledge of methane emissions from shale gas, conventional natural gas, coal, and petroleum, we estimated up-to-date life-cycle greenhouse gas emissions. In addition, we developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings that need to be further addressed. Our base case results show that shale gas life-cycle emissions are 6% lower than conventional natural gas, 23% lower than gasoline, and 33% lower than coal. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty whether shale gas emissions are indeed lower than conventional gas. Moreover, this life-cycle analysis, among other work in this area, provides insight on critical stages that the natural gas industry and government agencies can work together on to reduce the greenhouse gas footprint of natural gas.
Authors: Burnham, A.; Han, J.; Clark, C.E.; Wang, M.; Dunn, J.B.; Palou-Rivera, I.