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1.
The main objective of this research is to quantify the impact of introducing electric vehicles and plug-in hybrid vehicles, including fuel cell on conventional fleets. The impact is estimated in terms of local pollutants, HC, CO, NOx, PM, and in terms of CO2 and water vapour global emissions. The specific fleet of Portugal, roughly 6 million light-duty vehicles (30% diesel, 70% gasoline) is considered, and the mobility indicator of the fleet, 90 thousand million p × km, is kept constant throughout the analysis. Probability density functions for energy consumption and emissions are derived for conventional, electric and plug-in hybrid vehicles, in charge depleting and charge sustaining modes. The Monte Carlo method is used to obtain average distribution estimates for discounting values of “old vehicles” that are removed from the fleet, and to add average distribution estimates for the “new vehicles” entering the fleet. Considering the actual Portuguese fleet as the reference case, local pollutant emissions decrease by a factor of 10-53%, for 50% fleet replacement. A potential 23% decrease of CO2 is foreseen, and a potential 31% increase of H2O emissions is forecasted. Life cycle water vapour emissions tend to rise and are, typically, 2-4 times higher than CO2 values at the upstream stage, due to its release in the cooling towers of thermal power plants. It is interesting to note that considering 1 MJ of energy required at vehicle wheels, in an overall life cycle context, both fuel cell and electric modes have nearly twice as much H2O emissions than internal combustion vehicles. CO2 emissions tend to decrease with electric drive vehicles penetration due to the higher fleet life cycle efficiency.  相似文献   

2.
Hydrogen and electric vehicle technologies are being considered as possible solutions to mitigate environmental burdens and fossil fuel dependency. Life cycle analysis (LCA) of energy use and emissions has been used with alternative vehicle technologies to assess the Well-to-Wheel (WTW) fuel cycle or the Cradle-to-Grave (CTG) cycle of a vehicle's materials. Fuel infrastructures, however, have thus far been neglected. This study presents an approach to evaluate energy use and CO2 emissions associated with the construction, maintenance and decommissioning of energy supply infrastructures using the Portuguese transportation system as a case study. Five light-duty vehicle technologies are considered: conventional gasoline and diesel (ICE), pure electric (EV), fuel cell hybrid (FCHEV) and fuel cell plug-in hybrid (FC-PHEV). With regard to hydrogen supply, two pathways are analysed: centralised steam methane reforming (SMR) and on-site electrolysis conversion. Fast, normal and home options are considered for electric chargers. We conclude that energy supply infrastructures for FC vehicles are the most intensive with 0.03–0.53 MJeq/MJ emitting 0.7–27.3 g CO2eq/MJ of final fuel. While fossil fuel infrastructures may be considered negligible (presenting values below 2.5%), alternative technologies are not negligible when their overall LCA contribution is considered. EV and FCHEV using electrolysis report the highest infrastructure impact from emissions with approximately 8.4% and 8.3%, respectively. Overall contributions including uncertainty do not go beyond 12%.  相似文献   

3.
The claim of catastrophic man made climate change or global warming through anthropogenic CO2 has presently focused the interest on the tailpipe emissions of CO2 per km, with recent legislations obsessively targeting these emissions of CO2 with defectively implemented procedures. With a variety of different propulsion solutions (electric, hybrid electric, hybrid mechanic, conventional) and different fuels (Diesel, Petrol, alternative fossil, alternative renewable) available in the near future, a more comprehensive approach based on the full fuel cycle, and eventually also the full life cycle of the vehicle appear to be necessary. The paper is a contribution to trigger further improvement to currently implemented procedures. The paper discusses the CO2 emission data in the present form, some simple but effective measures to improve the accuracy of the data collection procedure, and propose results of fuel cycle CO2-e analysis of vehicles with electric and thermal engines having different fuels. Vehicles with advanced internal combustion engines and power trains fuelled with Diesel may reach CO2-e values of 100 g/km in Australia. Use of bio-ethanol in these vehicles may deliver in Australia a significant reduction of CO2-e emissions to values below 36 g/km. Emission factors for Victoria are presently 1.23 kg CO2-e/kWh for the purchased electricity and vehicles powered by electric motors will need a significant reduction of this indirect CO2-e emission to become competitive. Values below 0.5 kg CO2-e/kWh are needed to make electric cars competitive with Diesel cars while values below 0.1 kg CO2-e/kWh are needed to make electric cars competitive with bio-ethanol cars. Compared with all these alternatives, renewable hydrogen may possibly compete with Diesel when produced with renewable energy sources and made available at the pump for less than 0.1 kg CO2-e/MJ of fuel energy, and with bio-ethanol if produced and distributed at a cost below 0.02 kg CO2-e/MJ of fuel energy.  相似文献   

4.
This study assesses global light-duty vehicle (LDV) transport in the upcoming century, and the implications of vehicle technology advancement and fuel-switching on greenhouse gas emissions and primary energy demands. Five different vehicle technology scenarios are analyzed with and without a CO2 emissions mitigation policy using the GCAM integrated assessment model: a reference internal combustion engine vehicle scenario, an advanced internal combustion engine vehicle scenario, and three alternative fuel vehicle scenarios in which all LDVs are switched to natural gas, electricity, or hydrogen by 2050. The emissions mitigation policy is a global CO2 emissions price pathway that achieves 450 ppmv CO2 at the end of the century with reference vehicle technologies. The scenarios demonstrate considerable emissions mitigation potential from LDV technology; with and without emissions pricing, global CO2 concentrations in 2095 are reduced about 10 ppmv by advanced ICEV technologies and natural gas vehicles, and 25 ppmv by electric or hydrogen vehicles. All technological advances in vehicles are important for reducing the oil demands of LDV transport and their corresponding CO2 emissions. Among advanced and alternative vehicle technologies, electricity- and hydrogen-powered vehicles are especially valuable for reducing whole-system emissions and total primary energy.  相似文献   

5.
This paper analyses the energy consumption and CO2 emissions of biological hydrogen production from sugarcane and potato peels using life cycle assessment methodology for the Portuguese scenario. Potato peels are assumed to be produced locally from Portuguese potato cultivation. Sugarcane is assumed to be imported from Brazil and fermented in Portugal. The uncertainty is quantified by a Monte Carlo approach. Biohydrogen was compared with natural gas reforming, electrolysis and other energy resources such as diesel and electricity. Between bioH2 feedstocks, sugarcane stands out with the lowest values for energy consumption and CO2 emissions with 0.30–0.34 MJ of consumed energy and 24–31 g of CO2 emitted per 1 MJ of H2 produced. However these results do not have a major contribution to the Portuguese energy independency problem. On the other hand potato peels feedstocks are more attractive, presenting values of 0.49–0.61 MJ/MJH2 and 60-77 gCO2/MJH2. According to Portuguese production capabilities, it is estimated that biohydrogen will be able to supply 3100 vehicles of a typical Portuguese urban taxi fleet or up to 1.4 million passenger cars with a daily commuting distance of 30 km.  相似文献   

6.
Fuel cell vehicles, as the most promising clean vehicle technology for the future, represent the major chances for the developing world to avoid high-carbon lock-in in the transportation sector. In this paper, by taking China as an example, the unique advantages for China to deploy fuel cell vehicles are reviewed. Subsequently, this paper analyzes the greenhouse gas (GHG) emissions from 19 fuel cell vehicle utilization pathways by using the life cycle assessment approach. The results show that with the current grid mix in China, hydrogen from water electrolysis has the highest GHG emissions, at 3.10 kgCO2/km, while by-product hydrogen from the chlor-alkali industry has the lowest level, at 0.08 kgCO2/km. Regarding hydrogen storage and transportation, a combination of gas-hydrogen road transportation and single compression in the refueling station has the lowest GHG emissions. Regarding vehicle operation, GHG emissions from indirect methanol fuel cell are proved to be lower than those from direct hydrogen fuel cells. It is recommended that although fuel cell vehicles are promising for the developing world in reducing GHG emissions, the vehicle technology and hydrogen production issues should be well addressed to ensure the life-cycle low-carbon performance.  相似文献   

7.
《Journal of power sources》2006,155(2):297-310
The transportation sector is responsible for a great percentage of the greenhouse gas emissions as well as the energy consumption in the world. Canada is the second major emitter of carbon dioxide in the world. The need for alternative fuels, other than petroleum, and the need to reduce energy consumption and greenhouse gases emissions are the main reasons behind this study. In this study, a full life cycle analysis of an internal combustion engine vehicle (ICEV) and a fuel cell vehicle (FCV) has been carried out. The impact of the material and fuel used in the vehicle on energy consumption and carbon dioxide emissions is analyzed for Canada. The data collected from the literature shows that the energy consumption for the production of 1 kg of aluminum is five times higher than that of 1 kg of steel, although higher aluminum content makes vehicles lightweight and more energy efficient during the vehicle use stage. Greenhouse gas regulated emissions and energy use in transportation (GREET) software has been used to analyze the fuel life cycle. The life cycle of the fuel consists of obtaining the raw material, extracting the fuel from the raw material, transporting, and storing the fuel as well as using the fuel in the vehicle. Four different methods of obtaining hydrogen were analyzed; using coal and nuclear power to produce electricity and extraction of hydrogen through electrolysis and via steam reforming of natural gas in a natural gas plant and in a hydrogen refueling station. It is found that the use of coal to obtain hydrogen generates the highest emissions and consumes the highest energy. Comparing the overall life cycle of an ICEV and a FCV, the total emissions of an FCV are 49% lower than an ICEV and the energy consumption of FCV is 87% lower than that of ICEV. Further, CO2 emissions during the hydrogen fuel production in a central plant can be easily captured and sequestrated. The comparison carried out in this study between FCV and ICEV is extended to the use of recycled material. It is found that using 100% recycled material can reduce energy consumption by 45% and carbon dioxide emissions by 42%, mainly due to the reduced use of electricity during the manufacturing of the material.  相似文献   

8.
The paper compares the atmospheric emissions of different hydrogen production scenarios for various transportation modes in a case study for Ontario, Canada. Hydrogen demand scenarios are based on historical data of the various transportation modes. Predicting the CO2 emissions for a market with hydrogen vehicles against a purely fossil fuel market outlines the benefits of utilizing hydrogen. For road vehicles less than 4,500 kg in weight, emissions from a thermochemical production fraction of 20% produced a 9.8% decrease in CO2 emissions (or over 3,000 kilotonnes), compared to a 100% fossil fuel market. When these studies are applied to other transportation modes such as rail, air and marine, similar trends are observed. The largest benefits occur from automobiles and rail, where increasing carbon emission trends were reversed due to the increasing hydrogen propulsion base. Further decreases in carbon dioxide emissions could be realized by lower emitting production sources such as nuclear thermochemical production and electrolysis from wind, solar, and hydro.  相似文献   

9.
Magnesium (Mg) alloys are suitable materials for weight reduction in vehicles because of their low density of 1.7 g/cm3 and high specific strength. The effect of Mg substitution for conventional steel parts in a vehicle on total energy consumption and CO2 emissions was evaluated through life cycle inventory calculation. The Mg substitution reduces the total energy consumption by weight reduction, although the production energy of a Mg-substituted vehicle is higher than those of conventional and Al-substituted vehicles. The Mg substitution can save more life cycle energy consumption than the Al substitution. Recycling of Mg parts is indispensable for efficient CO2 reduction, because the CO2 emissions during new ingot production of Mg are much higher than those of conventional steel and Al. Strengthening of the Mg parts also can reduce the total energy consumption and CO2 emissions. If the main body and hood are made of Mg alloy and the ratio of recycled ingot is sufficiently high, the life cycle energy consumption and CO2 emissions will be markedly reduced.  相似文献   

10.
In this study, emissions of internal combustion engine, hybrid, and fuel cell vehicles have been investigated when they use hydrogen in gas or liquid form. Well to pump (WTP) and well to wheel (WTW) emissions of volatile organic compounds (VOC), carbon monoxide (CO), nitrogen oxides (NOx), particulate matters (PM10 and PM2.5), sulphur oxides (SOx), and carbon dioxide (CO2) emitted from vehicles are compared for scenarios in 2010, 2020, 2030, 2040, and 2050 years. For these years, 2005, 2015, 2025, 2035, and 2045 vehicle technologies are used in the analyses. In total emissions, gaseous hydrogen (GH2) powered fuel cell vehicles (FCV) appear to be the best options, while liquid hydrogen (LH2) powered spark ignition internal combustion engine vehicles (SI ICEV) are the worst. The lowest and highest CO2 emission values are seen as 81 g/km and 416 g/km in GH2 powered FCVs in 2050 and LH2 powered SI ICEVs in 2010, respectively.  相似文献   

11.
Exergetic life cycle assessment (ExLCA) is applied with life cycle assessment (LCA) to a hydrogen production process. This comparative environmental study examines a nuclear-based hydrogen production via thermochemical water splitting using a copper–chlorine cycle. LCA, which is an analytical tool to identify, quantify and decrease the overall environmental impact of a system or a product, is extended to ExLCA. Exergy efficiencies and air pollution emissions are evaluated for all process steps, including the uranium processing, nuclear and hydrogen production plants. LCA results are presented in four categories: acidification potential, eutrophication potential, global warming potential and ozone depletion potential. A parametric study is performed for various plant lifetimes. The ExLCA results indicate that the greatest irreversibility is caused by uranium processing. The primary contributor of the life cycle irreversibility of the nuclear-based hydrogen production process is fuel (uranium) processing, for which the exergy efficiency is 26.7% and the exergy destruction is 2916.3 MJ. The lowest global warming potential per megajoule exergy of hydrogen is 5.65 g CO2-eq achieved a plant capacity of 125,000 kg H2/day. The corresponding value for a plant capacity of 62,500 kg H2/day is 5.75 g CO2-eq.  相似文献   

12.
The commercial vehicles are in leadership in emission production for on-road vehicles. This high rate of emission is released in highly populated areas where diesel driven internal combustion engines are running in inefficient operating ranges. Except the propulsion, the internal combustion engine is powering the auxiliary devices such as refrigerator unit, etc. The auxiliary units are significant contributor to the overall pollutant production. In this paper the auxiliary load power supply for refrigerator unit is shifted from internal combustion engine to PEM fuel cell. The decrease in CO2 accumulated emissions was estimated by simulation model containing vehicle model (tire, brake, differential, gearbox and driver model), diesel engine model and auxiliary power demand model. Four stroke diesel engine was modeled and investigated. For this investigation the fully filled truck was used for simulating 100% weight load. The gross weight is 7500 kg.The novelty of the approach is the simulation performed on realistic combination of city and urban road cycle. The focus was on modelling the realistic truck driving cycle in order to correctly predict emission and fuel consumption reduction. Since initial investigation are performed on constant load demand of fuel cell, simplified model of PEMFC was applied. PEM fuel cell stack was designed in order to meet the demands of auxiliary consumers. The H2 consumption and size of hydrogen tank was estimated based on assumed 8-h daily drive. Finally, the migration of power supply for auxiliary units on commercial vehicle from internal combustion engine showed potential of fuel savings and CO2 reduction of up to 9% for a given case on this specific test cycle.  相似文献   

13.
Hydrogen energy carriers such as liquid hydrogen (LH2), methylcyclohexane (MCH), and ammonia (NH3) are promising energy vectors in the clean energy systems currently being developed. However, their effectiveness in mitigating environmental emissions must be assessed by life cycle analyses throughout the supply chain. In this study, while focusing on hydrogen energy carriers, life cycle inventory analyses were conducted to estimate CO2 emissions from the following types of power generation plants in Japan: a hydrogen (H2) mono-firing power plant using LH2 or MCH that originated from overseas renewable electricity; and NH3 co-firing with fossil fuel and NH3 mono-firing power plants using hydrogen energy carriers that originated from overseas natural gas or renewable electricity. Parameters related to the supply chains were collected by literature surveys, and the Japanese life cycle inventory database was primarily used to calculate the emissions. From the results, CO2 hotspots of the target supply chains and potential measures are identified that become necessary to establish low-carbon supply chains.  相似文献   

14.
Developing underground coal gasification (UCG)-based hydrogen production (UCG-H2) is expected to alleviate hydrogen supply and demand contradiction, but its energy consumption and environmental impact need to be clarified. In this paper, comparative study of energy consumption and greenhouse gas (GHG) emissions between UCG-H2 and typical surface coal gasification (SCG)-based hydrogen production (SCG-H2) is carried out using life cycle assessment method. Result shows energy consumption of UCG-H2 is only 61.2% of that of SCG-H2, which is 1,327,261 and 2,170,263 MJ respectively, reflecting its obvious energy saving advantage. 80% capture rate can achieve an appropriate balance between energy consumption and emissions. Under this capture rate, emissions of UCG-H2 and SCG-H2 are roughly equivalent, which are 207,582 and 197,419 kg CO2-eq respectively. Scenario analysis indicates energy consumption in hydrogen industry can reduce by 38.8% when hydrogen production is substituted by UCG with CCS to fully meet demand of 21 Mt in 2030.  相似文献   

15.
《Applied Thermal Engineering》2007,27(13):2294-2299
This paper provides a preliminary life cycle assessment (LCA) of polymer electrolyte membrane (PEM) fuel cell powered automobile. Life cycle of PEM fuel cell automobile not only includes operation of the vehicle on the road but also include production and distribution of both the vehicle and the fuel (e.g. hydrogen) during the vehicle’s entire lifetime. Assessment is based on the published data available in the literature. The two characteristics of the life cycle, which were assessed, are energy consumption and greenhouse gases (GHGs) emissions. Greenhouse gases (GHGs) emissions considered in the present assessment are CO2 and CH4. In addition, conventional internal combustion engine (ICE) automobile is also assessed based on similar characteristics for comparison with PEM fuel cell automobile. It is found that the energy utilized to generate the hydrogen during fuel cycle for the PEM automobile is about 3.5 times higher than the energy utilized to generate the gasoline during its fuel cycle. However, the overall life cycle energy consumption of PEM fuel cell automobile is about 2.3 times less than that of ICE automobile. Similarly, the GHGs emissions of PEMFC automobile are about 8.5 times higher than ICE automobile during the fuel cycle, but the overall life cycle GHGs emissions are about 2.6 times lower than ICE automobile.  相似文献   

16.
A commercially available ‘pure’ lead-acid battery electric scooter (GoPed) was converted to a hydrogen fuel cell battery hybrid scooter (HFCHS) in views of investigating the effect of hybridisation on driving duty cycles, range, performance, recharging times, well-to-wheel CO2 footprint and overall running costs. The HFCHS with plug-in features consisted mainly of a 500 W hydrogen PEM Fuel Cell stack connected to four 12 V 9 Ah lead-acid batteries and two hydrogen metal-hydride canisters supplying pure hydrogen (99.999%) and also acting as heat sink (due to endothermic hydrogen desorption process). In this study, the HFCHS urban driving cycle was compared with that of a conventional petrol and ‘pure’ battery electric scooter. The energy consumed by the HFCHS was 0.11 kWh/km, with an associated running cost of £0.01/km, a well-to-wheel CO2 of 9.37 g CO2/km and a maximum range of 15 miles. It was shown that the HFCHS gave better energy efficiencies and speeds compared to battery and petrol powered GoPed scooters alone.  相似文献   

17.
Electron beam plasma methane pyrolysis is a hydrogen production pathway from natural gas without direct CO2 emissions. In this work, two concepts for a technical implementation of the electron beam plasma pyrolysis in a large-scale hydrogen production plant are presented and evaluated in regards of efficiency, economics and carbon footprint. The potential of this technology is identified by an assessment of the results with the benchmark technologies steam methane reforming, steam methane reforming with carbon capture and storage as well as water electrolysis. The techno-economic analysis shows levelized costs of hydrogen for the plasma pyrolysis between 2.55 €/kg H2 and 5.00 €/kg H2 under the current economic framework. Projections for future price developments reveal a significant reduction potential for the hydrogen production costs, which support the profitability of plasma pyrolysis under certain scenarios. In particular, water electrolysis as direct competitor with renewable electricity as energy supply shows a considerably higher specific energy consumption leading to economic advantages of plasma pyrolysis for cost-intensive energy sources and a high degree of utilization. Finally, the carbon footprint assessment indicates the high potential for a reduction of life cycle emissions by electron beam plasma methane pyrolysis (1.9 kg CO2 eq./kg H2 – 6.4 kg CO2 eq./kg H2, depending on the electricity source) compared to state-of-the-art hydrogen production technology (10.8 kg CO2 eq./kg H2).  相似文献   

18.
Considerable attention has been paid to energy security and climate problems caused by road vehicle fleets. Fuel cell vehicles provide a new solution for reducing energy consumption and greenhouse gas emissions, especially those from heavy-duty trucks. Although cost may become the key issue in fuel cell vehicle development, with technological improvements and cleaner pathways for hydrogen production, fuel cell vehicles will exhibit great potential of cost reduction. In accordance with the industrial plan in China, this study introduces five scenarios to evaluate the impact of fuel cell vehicles on the road vehicle fleet greenhouse gas emissions in China. Under the most optimistic scenario, greenhouse gas emissions generated by the whole fleet will decrease by 13.9% compared with the emissions in a scenario with no fuel cell vehicles, and heavy-duty truck greenhouse gas emissions will decrease by nearly one-fifth. Greenhouse gas emissions intensity of hydrogen production will play an essential role when fuel cell vehicles' fuel cycle greenhouse gas emissions are calculated; therefore, hydrogen production pathways will be critical in the future.  相似文献   

19.
In this research study, a real model of a hydrogen fuel cell vehicle is simulated using Simcenter Amesim software. The software used for vehicle simulation enabled dynamic simulation, resulting in more precise simulation. Furthermore, considering that fuel cell degradation is one of the significant challenges confronting fuel cell vehicle manufacturers, we examined the impact of fuel cell degradation on the performance of hydrogen vehicles. According to the findings, a hydrogen vehicle with a degraded fuel cell consumes 14.3% more fuel than a fresh fuel cell hydrogen vehicle. A comprehensive life cycle assessment (LCA) is also performed for the designed hydrogen vehicle. The results of the hydrogen vehicle life cycle assessment are compared with a gasoline vehicle to fully understand the effect of hydrogen vehicles in reducing air emissions. The methods considered for hydrogen production included natural gas reforming, electrolysis, and thermochemical water splitting method. Furthermore, because the source of electricity used for electrolysis has a significant impact on the life cycle emission of a hydrogen vehicle, three different power sources were considered in this assessment. Finally, while a hydrogen vehicle with a degraded fuel cell emits lower carbon dioxide (CO2) than a gasoline vehicle, the emitted CO2 from this vehicle using hydrogen from electrolysis is approximately 25% higher than that of a new hydrogen vehicle.  相似文献   

20.
Hydrogen can compensate for the intermittent nature of some renewable energy sources and encompass the options of supplying renewables to offset the use of fossil fuels. The integrating of hydrogen application into the energy system will change the current energy market. Therefore, this paper deploys the life cycle cost analysis of hydrogen production by polymer electrolyte membrane (PEM) electrolysis and applications for electricity and mobility purposes. The hydrogen production process includes electricity generated from wind turbines, PEM electrolyser, hydrogen compression, storage, and distribution by H2 truck and tube trailer. The hydrogen application process includes PEM fuel cell stacks generating electricity, a H2 refuelling station supplying hydrogen, and range extender fuel cell electric vehicles (RE-FCEVs). The cost analysis is conducted from a demonstration project of green hydrogen on a remote archipelago. The methodology of life cycle cost is employed to conduct the cost of hydrogen production and application. Five scenarios are developed to compare the cost of hydrogen applications with the conventional energy sources considering CO2 emission cost. The comparisons show the cost of using hydrogen for energy purposes is still higher than the cost of using fossil fuels. The largest contributor of the cost is the electricity consumption. In the sensitivity analysis, policy supports such as feed-in tariff (FITs) could bring completive of hydrogen with fossil fuels in current energy market.  相似文献   

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