Near-term technologies for improving automotive efficiency - A review and update

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76698/1/AIAA-1994-4227-457.pd

Factor Analysis of Greenhouse Gas Emissions from Automobiles

Three approaches are commonly identified for controlling automobile greenhouse gas (GHG) emissions: reducing travel demand, improving vehicle efficiency and using alternatively (non-petroleum) fueled vehicles (AFVs). Similarly, sector emissions can be decomposed by travel distance, vehicle fuel intensity and fuel GHG ("carbon") intensity. Normalized analysis of these three factors offers valuable insights. For a broad set of conditions, any stringent GHG emissions limit for the automobile sector implies a limit of comparable stringency for fuel carbon intensity. However, carbon intensity is an abstraction of complex supply systems rather than an observable property of fuels (physical energy carriers) themselves. Carefully considering the locations and current magnitudes of fuel-related emissions implies that the proper policy focus is on upstream sectors that supply fuel rather than the choice of fuels downstream in the auto sector. Therefore, other than fundamental R&D, programs to promote AFVs are not currently warranted for climate protection. In addition to managing travel demand and improving vehicle efficiency, the implied climate policy priority is limiting net GHG emissions in fuel supply sectors. Future work is needed to develop GHG management policies for liquid fuel supply systems involving fungible commodities and dynamic global supply chains.Clean Energy Research Center Clean Vehicle Consortium (CERC-CVC) under U.S. Department of Energy award number DE-PI0000012.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94306/1/Factoring Car-Climate Challenge Oct 2012.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/94306/4/Factor Analysis of Auto GHGs 2012.pd

Addressing Biofuel GHG Emissions in the Context of a Fossil-Based Carbon Cap

Renewable fuels have been promoted as a climate solution as well as for their energy security and domestic economic benefits. Analysts often assume that, other than process emissions, biofuels emit no net CO2 because their biogenic carbon was recently absorbed from the atmosphere. This “renewability shortcut” has shaped both public perception and public policy to date. Cap-and-trade policies follow GHG inventory conventions that use the shortcut and so fail to properly account for biofuel emissions. They also miss portions of the upstream GHG emissions from fossil-based transportation fuels, although most such emissions are trade related. Lifecycle analysis (LCA), which attempts to account for all of the GHG impacts associated with fuel production, has been proposed as a means of regulating fuels for climate policy. LCA is used to qualify certain fuels for the U.S. federal renewable fuel standard (RFS) and also forms the basis of a low-carbon fuel standard (LCFS). However, as LCA system boundaries have expanded to address market effects such as induced land-use change, its application in policy has become controversial. This paper examines these issues, quantifies GHG emissions missed by cap-and-trade policies as commonly proposed, and identifies ways to address biofuel emissions in the context of a carbon cap that covers major emitting sectors. Resource economics suggests that policy should be defined by annual basis accounting of carbon stocks and flows and other GHG fluxes rather than by LCA. This perspective suggests the use of a three-part approach: (1) correct specification of the transportation sector point of regulation with careful carbon accounting at the point of finished fuel distribution; (2) voluntary fuel and feedstock GHG accounting standards to track CO2 uptake and uncapped GHG emissions throughout the fuel supply chain; and (3) a land protection fund for purchasing international forest carbon offsets to mitigate leakage. While an RFS can remain in place to drive volumes of specified fuels into the market, this approach avoids the need for either LCA requirements in the RFS or the added regulatory layer of an LCFS. Integrated into a cap-and-trade framework, this market-based approach would provide biofuel and feedstock production with a carbon price incentive tied to the cap, creating a more complete carbon management framework for the transportation fuels sector.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76029/1/Biofuels in Context jmd Oct 2009.pd

Biofuels and Carbon Management

Public policy supports biofuels for their benefits to agricultural economies, energy security and the environment. The environmental rationale is premised on greenhouse gas (GHG, "carbon") emissions reduction, which is a matter of contention. This issue is challenging to resolve because of critical but difficult-to-verify assumptions in lifecycle analysis (LCA), limits of available data and disputes about system boundaries. Although LCA has been the presumptive basis of climate policy for fuels, careful consideration indicates that it is inappropriate for defining regulations. This paper proposes a method using annual basis carbon (ABC) accounting to track the stocks and flows of carbon and other relevant GHGs throughout fuel supply chains. Such an approach makes fuel and feedstock production facilities the focus of accounting while treating the CO2 emissions from fuel end-use at face value regardless of the origin of the fuel carbon (bio- or fossil). Integrated into cap-and-trade policy and including provisions for mitigating indirect land-use change impacts, also evaluated on an annual basis, an ABC approach would provide a sound carbon management framework for the transportation fuels sector.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86104/1/Biofuels and Carbon Management FINAL for CC 2011.pd

A Fuel Efficiency Horizon for U.S. Automobiles

Technical report, 55 pages with 6 tables, 18 figures, appendix and 112 references.Improving the fuel efficiency of automobiles (cars and light trucks) is an important means of addressing transportation oil demand and greenhouse gas (GHG) emissions. This report examines the efficiency attainable through evolutionary changes in U.S. automobiles that have fueling characteristics as well as performance, size and other attributes similar to those of today. The analysis combines results from previous engineering studies of powertrain efficiency and load reduction with new examinations of rates of technology change and cost reduction. It introduces the concept of "efficiency-compatible" vehicle design for product planning strategies that address the trade-off between fuel economy and other vehicle features. A logistical model is applied to characterize historical rates of technology adoption and identify feasible adoption rates for new technologies such as hybrid drive. Costs are modeled as a quadratic function of the reduction in vehicle energy use rate, with parameters reflecting technological progress that results in declining costs over time. The conclusion is that a tripling of new fleet fuel efficiency is an ambitious but defensible horizon for 2035. That would improve average on-road fuel economy from a baseline of 20 mpg in 2005 to 60 mpg by 2035. The projected per vehicle retail-equivalent cost averages $4,200 and the discounted lifetime benefit is$8,800 (2010$, assuming an average motor fuel shadow price of$2.88/gal). Although the analysis is technologically neutral, reaching this efficiency level is likely to entail high adoption of hybrid drive as well as advanced combustion engines and steady incremental progress in mass reduction and streamlining. Most importantly, it will require market prioritization of vehicle efficiency improvement over further improvement of other features, particularly acceleration performance, that trade off against it.The Energy FoundationPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78178/1/DeCicco_AutoEfficiencyHorizon_Sept2010.pd

Vehicle Standards in a Climate Policy Framework

Policy makers have long turned to vehicle regulation for addressing public concerns about transportation's energy and environmental impacts. This paradigm is ratified in recent action to raise Corporate Average Fuel Economy (CAFE) standards and issue vehicle greenhouse gas (GHG) emissions standards both in California and federally. At the same time, U.S. policy makers are moving toward a national program to limit GHG emissions economy wide. The most robust strategy entails capping emissions from all major sectors including transportation. Such a policy would place an overall constraint on the dominant, carbon dioxide (CO2) portion of vehicle GHG emissions, which are also regulated by vehicle standards. This overlap raises questions of how vehicle-specific regulations should relate to the broader policy and what metric vehicle standards should use in such a context. Answers can be found by reviewing the strengths and weaknesses of past policies and drawing on recent discussions regarding the design of national climate policy. One conclusion is that climate policy should require agencies to administer vehicle standards as part of an overall transportation sector GHG management plan that explicitly considers the costs and benefits of the standards relative to other measures that affect emissions. Another is that vehicle standards should be based on an energy metric rather than on GHG emissions rates, which depend on the fuel supply system and not just the vehicle itself. In general, vehicle standards should be promulgated as part of a policy structure that provides appropriate incentives for all actors in the sector: fuel suppliers, transportation infrastructure and land-use planners, consumers and vehicle manufacturers. Such an approach will ensure balanced and ongoing progress in limiting transportation emissions in a manner reasonably commensurate with national climate protection goals, such as those defined by a declining cap on GHG emissions economy wide.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76030/1/Vehicle Standards in Climate Framework Jan 2010.pd

Toward Rational Management of GHG Emissions from Biofuels

Public policy supports biofuels for their benefits to agricultural economies, energy security and the environment. The last rationale is premised on greenhouse gas (GHG, "carbon") emissions reduction, which is a matter of contention. The issue is challenging to resolve because of critical but difficult-to-verify assumptions in lifecycle analysis (LCA), limits of available data and disputes about system boundaries. Although LCA has been the presumptive basis of climate policy for fuels, careful consideration indicates that it is inappropriate for defining regulations. This paper proposes a method using annual basis carbon (ABC) accounting to track the stocks and flows of carbon and other relevant GHGs throughout fuel supply chains. Such an approach makes fuel and feedstock production facilities the focus of accounting while treating the CO2 emissions from fuel end-use at face value regardless of the origin of the fuel carbon (bio- or fossil). Integrated into cap-and-trade policy and including provisions for mitigating indirect land-use change impacts, also evaluated on an annual basis, an ABC approach would provide a sound carbon management framework for the transportation fuels sector.http://deepblue.lib.umich.edu/bitstream/2027.42/78278/1/Toward_Rational_Mgmt_GHGs_Biofuels.pd

Pumping the Brakes on Robot Cars: Current Urban Traveler Willingness to Consider Driverless Vehicles

A growing literature suggests that widespread travel conducted through driverless connected and automated vehicles (CAVs) accessed as a service, in contrast to those personally owned, could have significant impacts on the sustainability of urban transportation. However, it is unclear how the general public currently considers willingness to travel in driverless vehicles, and if they would be more comfortable doing so in one personally owned or one accessed as a service. To address this, we collected travel survey data by intercepting respondents on discretionary or social trips to four popular destinations in a medium-size U.S. city in the spring of 2017. After collecting data on how the respondent reached the survey site and the trip’s origin and destination, survey administrators then asked if respondents would have been willing to make their current trip in either a personally-owned driverless vehicle or through a driverless vehicle service. Over one-third expressed willingness to use both forms, while 31% were unwilling to use either. For those that considered only one, slightly more favored the personally-owned model. Consideration of an existing mobility service was consistently a positive and significant predictor of those that expressed willingness to travel in a driverless vehicle, while traveling downtown negatively and significantly influenced consideration of at least one form of driverless vehicle. These findings highlight the diverse public views about the prospect of integration of CAVs in transportation systems and raise questions about the assumption that travelers to central city locations would be early adopters of automated vehicle mobility services.The research reported here was supported in part by the U.S. Environmental Protection Agency (EPA), SPEED Program Grant No. 83594901the University of Michigan Energy Institute (UMEI) and University of Michigan Dow Sustainability Fellows progra

Renewable energy resource assessment

© The Author(s) 2019. Literature overview of published global and regional renewable energy potential estimates. This section provides definitions for different types of RE potentials and introduces a new category, the economic renewable energy potential in space constrained environments. The potential for utility scale solar and onshore wind in square kilometre and maximum possible installed capacity (in GW) are provided for 75 different regions. The results set the upper limits for the deployment of solar- and wind technologies for the development of the 2.0 °C and 1.5 °C energy pathways