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1.
Costs of producing “advanced” biofuels (those with the lowest GHG and land use impacts) have not decreased in recent years as envisioned by analysts. Despite aggressive policy incentives, no transition to a lower cost mature industry has occurred. Information about the cost dynamics and slow industry emergence is of major interest to policymakers and others seeking to understand the likely success – and cost – of incentive programs. This paper reviews literature on production cost at the plantgate – without considering taxes or delivery costs – for selected biofuel technology pathways using a levelized cost of fuel approach, applying common financing assumptions for capital amortization and converting all values to year 2016 dollars, and examines results in the current low carbon fuel policy context. The average production cost estimate for cellulosic ethanol was $4 per gallon-gasoline equivalent (gge). For drop-in fuels, the pyrolysis-biocrude-hydro treatment pathway had the lowest average production cost estimate at about $3.25/gge. Biomass to liquid (BTL) production cost estimates averaged $3.80/gge, while hydrotreated esters and fatty acids (HEFA) – the sole fuel studied gaining commercial traction – averaged about $3.70/gge. Estimate ranges did not allow any definitive rank ordering of the fuels by production cost. Production cost estimates are higher in later than in earlier publications for non-HEFA fuels due primarily to higher costs for feedstock and capital expenditure components. This may reflect learning from early but largely unsuccessful commercialization efforts that yielded more realistic (and higher cost) information and detail on feedstock provision and conversion processes.  相似文献   

2.
This study provides a comprehensive comparison of well-to-wheel (WTW) energy demand, WTW GHG emissions, and costs for conventional ICE and alternative passenger car powertrains, including full electric, hybrid, and fuel cell powertrains. Vehicle production, operation, maintenance, and disposal are considered, along with a range of hydrogen production processes, electricity mixes, ICE fuels, and battery types. Results are determined based on a reference vehicle, powertrain efficiencies, life cycle inventory data, and cost estimations. Powertrain performance is measured against a gasoline ICE vehicle. Energy carrier and battery production are found to be the largest contributors to WTW energy demand, GHG emissions, and costs; however, electric powertrain performance is highly sensitive to battery specific energy. ICE and full hybrid vehicles using alternative fuels to gasoline, and fuel cell vehicles using natural gas hydrogen production pathways, are the only powertrains which demonstrate reductions in all three evaluation categories simultaneously (i.e., WTW energy demand, emissions, and costs). Overall, however, WTW emission reductions depend more on the energy carrier production pathway than on the powertrain; hence, alternative energy carriers to gasoline for an ICE-based fleet (including hybrids) should be emphasized from a policy perspective in the short-term. This will ease the transition towards a low-emission fleet in Switzerland.  相似文献   

3.
This study addresses the dearth of research that examines the impacts of alternative fuel use on operational costs of public transit in the U.S. Specifically, the study examines the impact on operational costs of shifting diesel gallons to biodiesel or to compressed natural gas (CNG) for an unbalanced panel of 269 public transit systems in the U.S. from 2008 through 2012, using an econometric cost function approach. We find that shifting all diesel gallons to biodiesel results in operational cost increases ranging from 1 to 12 percent, with smaller cost increases being realized with increases in system size. Shifting all diesel gallons to CNG results in operational cost increases between 5 and 10 percent – again with smaller impacts for larger systems. These findings suggest that there are some economies of using biodiesel and CNG with large scale production. That is, the cost increases associated with increased fuel prices, decreased fuel economy, increased maintenance costs, and increased fueling costs associated with biodiesel and CNG are mitigated somewhat by large scale production. The findings of this study suggest that increased operational costs are an important consideration in policies aimed at encouraging the use of alternative fuels by U.S. public transit systems.  相似文献   

4.
The transition to low-carbon transportation fuels plays a key role in ongoing efforts to combat climate change. This analysis seeks to optimize potential alternative fuel portfolios that would lead to a 10% reduction in fuel carbon intensity by 2020 as required under California’s Low Carbon Fuel Standard (LCFS).We present a novel, probabilistic modeling approach for evaluating alternative fuel portfolios based on their marginal greenhouse gas (GHG) abatement costs. Applied to a case study region in Northwest California, our model enables us to quantify the financial cost of GHG reduction via each fuel pathway, as well as for a portfolio deployed to meet the LCFS target. It also enables us to explore the sensitivity of the alternative fuel portfolio, evaluating the impact of fluctuating prices, fuel carbon intensities, and technology penetrations on the makeup of the portfolio and on the average cost of GHG abatement.We find that battery electric vehicles play a critical role, as they offer the lowest-financial-cost significant abatement in almost all plausible scenarios. However, electric vehicles alone will not be sufficient to reach the target; low-carbon biofuels can be expected to play a role in the achievement of 2020 Low Carbon Fuel Standard targets.  相似文献   

5.
In this study, the costs involved in the use of petrol, diesel, natural gas, biogas, and methanol (produced from natural gas and biomass) in cars and heavy trucks are compared. The cost includes fuel cost, extra capital cost for vehicles using alternative fuels, and the environmental cost of VOC, NOx, particulate and CO2 emission based on actual 1996 and estimated 2015 emission factors. The costs have been calculated separately for rural, urban and city-centre traffic. A complete macroeconomic assessment of the effect of introducing alternative fuels is not, however, included in the study. The study shows that no alternative fuel can compete with petrol and diesel in rural traffic when the economic valuation of CO2 emission is taken as current Swedish CO2 taxes ($200/tonne C). In cities with a natural gas network, natural gas is the fuel with the lowest cost for both cars and heavy trucks, based on 1996 emission factors. Methanol from natural gas and biogas from waste products can also compete with diesel in urban traffic. With predicted improvements in technology and subsequent emission reductions, no alternative fuel can compete with petrol in any of the traffic situations studied by 2015, and only in city-centre traffic will alternative fuels be less costly than diesel in heavy vehicles. Of the biomass-based fuels studied, low-cost biogas from waste products is the most competitive one and is, already at current CO2 taxes, the fuel with lowest cost for heavy trucks in urban traffic in areas where natural gas networks do not exist. To enable the more widespread use of biomass-based fuels, i.e. using feedstocks such as energy crops or logging residues that are available in larger amounts, the economic valuation of CO2 emission has to be 2–2.5 times higher than current Swedish CO2 tax level.  相似文献   

6.
This paper describes a life cycle model for performing level-playing field comparisons of the emissions, costs, and energy efficiency trade-offs of alternative fuel vehicles (AFV) through the fuel production chain and over a vehicle lifetime. The model is an improvement over previous models because it includes the full life cycle of the fuels and vehicles, free of the distorting effects of taxes or differential incentives. This spreadsheet model permits rapid analyses of scenarios in plots of trade-off curves or efficiency frontiers, for a wide range of alternatives with current and future prices and levels of technology. The model is available on request.The analyses indicate that reformulated gasoline (RFG) currently has the best overall performance for its low cost, and should be the priority alternative fuel for polluted regions. Liquid fuels based on natural gas, M100 or M85, may be the next option by providing good overall performance at low cost and easy compatibility with mainstream fuel distribution systems. Longer term, electric drive vehicles using liquid hydrocarbons in fuel cells may offer large emissions and energy savings at a competitive cost. Natural gas and battery electric vehicles may prove economically feasible at reducing emissions and petroleum consumption in niches determined by the unique characteristics of those systems.  相似文献   

7.
This paper presents an analysis of a market-based policy aimed at encouraging manufacturers to develop more fuel efficient vehicles without affecting the car buyer’s choice of vehicle size. A vehicle’s size is measured by its “footprint”, the product of track width and wheelbase. Traditional market-based policies to promote higher fuel economy, such as higher gasoline taxes or gas guzzler taxes, also induce motorists to purchase smaller vehicles. Whether or not such policies affect overall road safety remains controversial, however. Feebates, a continuous schedule of new vehicle taxes and rebates as a function of vehicle fuel consumption, can also be made a function of vehicle size, thus removing the incentive to buy a smaller vehicle. A feebate system based on a vehicle’s footprint creates the same incentive to adopt technology to improve fuel economy as simple feebate systems while removing any incentive for manufacturers or consumers to downsize vehicles.  相似文献   

8.
Heavy fuels are likely to remain the dominant fuel source for two-stroke, low-speed diesel engines for large ship propulsion for the next decade or more. There is however, potential for increased use of pure vegetable oils (PVO) as an alternative and, by emitting lower levels of several pollutants, this can help the attainment of Annex VI of the MARPOL 73/78 convention aimed at large ships using fuels with less than 4.5% sulphur or 1.5% sulphur in SOX emission control areas The use of alternative fuels can also influence the attainment of the Kyoto protocol that requires greenhouse gas emissions to be reduced by 5% by 2010 compared to 1990. This paper analyses the physical and chemical properties of various pure vegetable oils as an alternative to heavy fuel oil for large ship propulsion.  相似文献   

9.
This paper considers some of the impacts of adopting hydrogen fuel cell powered electric automobiles in the US. The change will need significant adjustments to the electrical generation industry including additional capital and hydrocarbon fuel consumption as well as impacting anthropogenic greenhouse emissions. Examining the use of three fuels to generate hydrogen fuels, using three production methods, distributed in three geographic scenarios, we determine that while the change reduces anthropogenic greenhouse emissions with minimal additional electrical generation capital expenditures, it accelerates the use of natural gas. Electrolysis provides a sustainable, longer-term solution, but requires more capital investment in electrical generation and yields an increase in anthropogenic greenhouse emissions.  相似文献   

10.
The starting point of this paper is to consider that there is no general answer to the question of the equity of urban road pricing. We therefore simulate and compare the distributional effects on commuters of nine toll scenarios for Paris, assuming that utility is nonlinear in income. We show that the distributional pattern across income groups depends crucially on the level of traffic reduction induced by tolling. Stringent tolls are more favourable to low-income motorists. Equity effects also vary with toll design. Compared to a reference scenario which uniformly charges all motorists driving within Paris, an inbound cordon toll is detrimental to low-incomes. Conversely, granting a rebate to low CO2 emission cars slightly improves their situation while an exemption for Paris residents is neutral. Surprisingly, it matters little for social equity whether toll revenues are allocated to all commuters or solely to public transport users.  相似文献   

11.
In 2016, the International Maritime Organization (IMO) decided on global regulations to reduce sulphur emissions to air from maritime shipping starting 2020. The regulation implies that ships can continue to use residual fuels with a high sulphur content, such as heavy fuel oil (HFO), if they employ scrubbers to desulphurise the exhaust gases. Alternatively, they can use fuels with less than 0.5% sulphur, such as desulphurised HFO, distillates (diesel) or liquefied natural gas (LNG). The options of lighter fuels and desulphurisation entail costs, including higher energy consumption at refineries, and the present study identifies and compares compliance options as a function of ship type and operational patterns.The results indicate distillates as an attractive option for smaller vessels, while scrubbers will be an attractive option for larger vessels. For all vessels, apart from the largest fuel consumers, residual fuels desulphurised to less than 0.5% sulphur are also a competing abatement option. Moreover, we analyse the interaction between global SOX reductions and CO2 (and fuel consumption), and the results indicate that the higher fuel cost for distillates will motivate shippers to lower speeds, which will offset the increased CO2 emissions at the refineries. Scrubbers, in contrast, will raise speeds and CO2 emissions.  相似文献   

12.
Ever stricter emission regulations stimulate vessel owners to consider the adoption of alternative marine fuels, such as Liquefied Natural Gas (LNG). In deciding whether to invest in LNG-fueled vessels, initial investment and operating costs are decisive factors that have not yet been fully studied in the literature. In this paper, we present a new investment appraisal method to compare the costs of LNG-fueled vessels with conventional vessels. We analyze the fuel costs and overall exploitation costs by simulating bunker planning decisions under stochastic fuel prices, presence in emission controlled areas, and route lengths. Our analyses reveal that the fuel costs of LNG-fueled vessels are often lower than those of conventional vessels, even under unfavorable LNG prices. Due to the higher initial investment costs in LNG-fueled vessels, these fuel cost reductions do not always translate into lower overall exploitation costs. By conducting numerical experiments, we identified conditions under which the exploitation costs of LNG-fueled vessels are lower than conventional vessels.  相似文献   

13.
In order to reduce the number of vehicles stuck in congestion, especially for stop-and-go traffic at toll plazas, the establishment of electronic toll collection (ETC) systems has been a hot issue and dominant trend in many countries. Taiwan has joined the crowd, adding an ETC system to its toll roads in early 2006. However, despite the potential benefits for motorists, the utilization rate has been lower than expected during the introductory stage. The objective of this study is to advance our understanding on the critical antecedents of motorists’ intention of ETC service adoption by integrating both technology acceptance model (TAM) and theory of planned behavior (TPB) perspectives. Through empirical data collection and analysis from highway motorists who had not installed on-board units (OBU) for ETC service in Taiwan, we found that system attributes, perceived usefulness and perceived ease of use, indeed, positively engender motorists’ attitudes towards ETC service adoption. Moreover, results also reveal that attitude, subjective norm and perceived behavioral control positively influence the intention of ETC system adoption. Implications for practitioners and researchers, and suggestions for future research are also addressed in this study.  相似文献   

14.
Currently existing models of parking choice behaviour typically focus on the choice of types of parking spaces. Implicitly these models assume that motorists have a free choice in that spaces are available. The adaptive behaviour which they reveal when faced with congested parking spaces is not explicitly modelled. The aim of this paper is to contribute to the growing literature on parking choice modelling by developing and testing a stated choice model of adaptive behaviour of motorists who are faced with fully occupied parking lots. The findings of the analyses indicate that the model performs satisfactory as indicated by its goodness-of-fit and the fact that all significant parameters were in anticipated directions.  相似文献   

15.
Environmental considerations, concerning the negative impacts of ship exhaust gases and particles on ambient air quality, are behind the requirements of cleaner marine fuels currently applied in designated emission control areas (ECAs). We investigated the impact of a ship operating on two types of fuel on the indoor air quality onboard. Gaseous and particulate air pollutants were measured in the engine room and the accommodation sections on-board an icebreaker operating first on Heavy Fuel Oil (HFO, 1%-S), and later Marine Diesel Oil (MDO, 0.1%-S). Statistically significant decrease of SO2, NOx, PM2.5 and particle number concentration were observed when the ship was operating on MDO. Due to the higher content of alkylated PAHs in MDO compared to HFO, the concentration of PAHs increased during operation on MDO. The particulate PAHs classified as carcinogens, were similar to or lower in the MDO campaign. Chemical analysis of PM2.5 revealed that the particles consisted mainly of organic carbon and sulfate, although the fraction of metals was quite large in particles from the engine room. Principal Component Analysis of all measured parameters showed a clear difference between HFO and MDO fuel on the indoor environmental quality on-board the ship. This empirical study poses a first example on how environmental policy-making impacts not only the primary target at a global level, but also brings unexpected localized benefits at workplace level. The study emphasizes the need of further investigations on the impact of new marine fuels and technologies on the indoor air environments on board.  相似文献   

16.
Pollution by marine fuels and their influence on ecosystems and the human populace are growing concerns in the maritime industry. Consequently, emission regulations, alternate marine fuels and fuel efficiency enhancements are being pursued to ensure that marine emissions are curtailed within acceptable limits. Many strategic decisions related to these areas are taken based on cost and emission estimates which in turn depend on the accuracy of the estimation of marine fuel consumptions. The estimates are based on various methodologies which attempt to capture maritime fuel consumptions at local, regional and global levels. The bottom-up approach is the most predominant method to estimate emissions and thereby to assess compliance with the emissions regulations. The bottom-up methodologies rely heavily on average values of specific fuel consumptions and engine load factors. A case study which utilizes in-situ data is conducted to investigate the accuracy of the current approach and the results are compared with the estimates based on bottom-up approaches found in the literature. The findings revealed significant variations between the estimates and the actual fuel consumptions informing implications of unrealistic cost and emission estimates. As a solution the paper suggests a new concept in order to establish more reliable estimations of fuel consumptions and hence emissions predictions.  相似文献   

17.
Public service fleets offer an attractive option for introducing new renewable fuels on a large scale, which allow for the reduction of both greenhouse gas emissions and exhaust air pollutants. This study examines the use of biomethane (bio-CNG) and compressed natural gas for part of the bus fleet in Dublin, Ireland. The emissions produced from the 2008 fleet based at one of the city’s seven bus depots are compared to use of new diesel and bio-CNG buses. The optimum feedstock for bio-CNG production in Ireland was then investigated, as well as the quantity of feedstock needed to produce the required bio-CNG to fuel the bus fleet examined. As expected the results showed a substantial decrease in all exhaust emissions from the use of bio-CNG buses compared the 2008 fleet. Grass silage was chosen as the optimum feedstock for production of bio-CNG in Ireland.  相似文献   

18.
This paper investigates the well-to-wake energy consumption and greenhouse gas emissions of several key SOX abatement options in marine transportation, ranging from the manufacture of low sulfur fuels to equipping the vessel with suitable scrubber solutions. The findings suggest that a scrubber system, used with current heavy fuel oils, has the potential to reduce SOX emissions with lower well-to-wake energy consumption and greenhouse gas emissions than switching to production of low sulfur fuels at the refinery. A sensitivity analysis covering a series of system parameters shows that variations in the well-to-tank greenhouse gas emissions intensity and the energy efficiency of the main engine have the highest impacts in terms of well-to-wake emissions.  相似文献   

19.
Many metropolitan areas in the United States use vehicle inspection and maintenance (I/M) programs as a means of identifying high-polluting vehicles. While the effectiveness of such programs is debatable, the cost is undeniable, with millions of dollars spent in testing and millions more lost in the time motorists expend to participate in such programs. At the core of these costs is the blanket approach of requiring all vehicles to be tested. This paper sets the groundwork for a procedure that can be used to selectively target those vehicles most likely to be pollution violators. Using I/M data collected in the Seattle area in 1994, carbon monoxide, carbon dioxide and hydrocarbon emissions were modeled simultaneously using three-stage least squares. Our results show that vehicle age, vehicle manufacturer, number of engine cylinders, odometer reading, and whether or not oxygenated fuels were in use all play a significant role in determining I/M emission test results and these statistical findings can be used to form the basis for the selective sampling of vehicles for I/M testing.  相似文献   

20.
The rate at which fuel cell vehicles (FCVs) might displace the conventional fleet is examined under constraints imposed by the limited availability of platinum. It concludes that a transition period as short as 31 years is not feasible. Under the most favorable circumstances, a complete transition of the US fleet to this new technology would require about 66 years and 10,800 net tonnes of platinum. Platinum demand for the US auto industry alone would amount to 48% of world production during much of that transition period. The effect of that demand on the price of platinum would add to the problem of reducing vehicle cost to a competitive range. If US platinum consumption were to remain at its current level of 16% of annual world production, fleet conversion would require 146 years. These results imply that, without alternative catalysts, fuel cells alone cannot adequately address the issues facing the current system of road transport.  相似文献   

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