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1.
Life cycle assessment of greenhouse gas emissions from plug-in hybrid vehicles: implications for policy 总被引:1,自引:0,他引:1
Plug-in hybrid electric vehicles (PHEVs), which use electricity from the grid to power a portion of travel, could play a role in reducing greenhouse gas (GHG) emissions from the transport sector. However, meaningful GHG emissions reductions with PHEVs are conditional on low-carbon electricity sources. We assess life cycle GHG emissions from PHEVs and find that they reduce GHG emissions by 32% compared to conventional vehicles, but have small reductions compared to traditional hybrids. Batteries are an important component of PHEVs, and GHGs associated with lithium-ion battery materials and production account for 2-5% of life cycle emissions from PHEVs. We consider cellulosic ethanol use and various carbon intensities of electricity. The reduced liquid fuel requirements of PHEVs could leverage limited cellulosic ethanol resources. Electricity generation infrastructure is long-lived, and technology decisions within the next decade about electricity supplies in the power sector will affectthe potential for large GHG emissions reductions with PHEVs for several decades. 相似文献
2.
This study examines how driving patterns (distance and conditions) and the electricity generation supply interact to impact well-to-wheel (WTW) energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW performance of a PHEV is compared with that of a similar (nonplug-in) gasoline hybrid electric vehicle and internal combustion engine vehicle (ICEV). Driving PHEVs for short distances between recharging generally results in lower WTW total and fossil energy use and GHG emissions per kilometer compared to driving long distances, but the extent of the reductions depends on the electricity supply. For example, the shortest driving pattern in this study with hydroelectricity uses 81% less fossil energy than the longest driving pattern. However, the shortest driving pattern with coal-based electricity uses only 28% less fossil energy. Similar trends are observed in reductions relative to the nonplug-in vehicles. Irrespective of the electricity supply, PHEVs result in greater reductions in WTW energy use and GHG emissions relative to ICEVs for city than highway driving conditions. PHEVs charging from coal facilities only reduce WTW energy use and GHG emissions relative to ICEVs for certain favorable driving conditions. The study results have implications for environmentally beneficial PHEV adoption and usage patterns. 相似文献
3.
Rivela B Moreira MT Bornhardt C Méndez R Feijoo G 《Environmental science & technology》2004,38(6):1901-1909
A representative leather tannery industry in a Latin American developing country has been studied from an environmental point of view, including both technical and economic analysis. Life Cycle Analysis (LCA) methodology has been used for the quantification and evaluation of the impacts of the chromium tanning process as a basis to propose further improvement actions. Four main subsystems were considered: beamhouse, tanyard, retanning, and wood furnace. Damages to human health, ecosystem quality, and resources are mainly produced by the tanyard subsystem. The control and reduction of chromium and ammonia emissions are the critical points to be considered to improve the environmental performance of the process. Technologies available for improved management of chromium tanning were profoundly studied, and improvement actions related to optimized operational conditions and a high exhaustion chrome-tanning process were selected. These actions related to the implementation of internal procedures affected the economy of the process with savings ranging from US dollars 8.63 to US dollars 22.5 for the processing of 1 ton of wet salt hides, meanwhile the global environmental impact was reduced to 44-50%. Moreover, the treatment of wastewaters was considered in two scenarios. Primary treatment presented the largest reduction of the environmental impact of the tanning process, while no significant improvement for the evaluated impact categories was achieved when combining primary and secondary treatments. 相似文献
4.
In-use measurement of activity, energy use, and emissions of a plug-in hybrid electric vehicle 总被引:1,自引:0,他引:1
Plug-in hybrid electric vehicles (PHEVs) could reduce transportation air emissions and energy use. However, a method is needed for estimating on-road emissions of PHEVs. To develop a framework for quantifying microscale energy use and emissions (EU&E), measurements were conducted on a Toyota Prius retrofitted with a plug-in battery system on eight routes. Measurements were made using the following: (1) a data logger for the hybrid control system; (2) a portable emissions measurement system; and (3) a global positioning system with barometric altimeter. Trends in EU&E are estimated based on vehicle specific power. Energy economy is quantified based on gasoline consumed by the engine and grid energy consumed by the plug-in battery. Emissions from electricity consumption are estimated based on the power generation mix. Fuel use is approximately 30% lower during plug-in battery use. Grid emissions were higher for CO?, NO(x), SO?, and PM compared to tailpipe emissions but lower for CO and hydrocarbons. EU&E depends on engine and plug-in battery operation. The use of two energy sources must be addressed in characterizing fuel economy; overall energy economy is 11% lower if including grid energy use than accounting only for fuel consumption. 相似文献
5.
The sector of protective textiles was one of the European Lead Market Initiatives launched in 2012. As a result seven research and development projects were financed to support new and innovative products to enter to this market to increase safety at work. Also the legislation within Europe has a tendency towards this aim having higher impact on professional than on private clothing. If it is not possible to decrease the risks of a work place, the employer shall provide personal protective equipment (PPE), of which protective clothing is an essential part. In order to facilitate the choice, use and control of PPE, a large amount of EN standards and technical reports have been developed and published including requirements, classifications, test methods to be used, terminology and SUCAM. However, in the selection criteria, the environmental impact related with the production, use and disposal of different materials available in the market. In order to overcome this limitation within the SAFEPROTEX project, environmental impact of three different uniforms was evaluated using Life Cycle Analysis in comparison to reference garments. 相似文献
6.
对苏州某造纸企业新旧两条废水处理工艺的生命周期环境影响进行了对比研究。研究范围划定为:污水处理设施的建设阶段、运行阶段、污水处理设施的拆除阶段,通过统一的功能单位计算整理得到两条不同废水处理工艺的清单数据表。采用日本的AIST-LCAVer4评价软件进行影响评价,最终求得单一的生态指标:生态化的币值Yen。研究结果表明:上超滤前和上超滤后两套处理工艺的生态化币值分别为1.40Yen和1.15Yen,可见上超滤后对环境的影响比上超滤前的影响要小,其中药品对环境影响最大的为PAC的生产及使用。两套废水处理装置单项污染物排放量所占份额最大的是CO2,但上超滤后比上超滤前CO2的排放量下降了一半多,由原先的45.5kg/t纸降到21.9kg/t纸。造纸废水治理工艺的主要环境影响为城市空气污染、全球变暖、固体废弃物和资源消耗。我们认为,所获得的结论较为客观地反映了两种造纸废水治理工艺对环境的影响,可以作为中国造纸废水治理决策的参考依据。 相似文献
7.
综述了电加热型烟草制品中加热器具的能量供应单元及其市场主流技术, 简述了其生产工艺流程, 分析了存在的不足与研究方向。结果表明, 锂离子电池作为电加热型卷烟中加热器具的供能元器件, 具有体积能量密度要求高且大电流放电的特点, 其性能决定了加热器具的续航时间、充电速度、预热等待时间以及使用寿命等关键参数。在进行新型烟草制品研发时, 研究和开发更高能量密度、高充放电倍率以及高安全性能的锂离子电池, 对促进我国新型烟草的高质量发展以及提升消费者体验具有重要意义。 相似文献
8.
为获得性能较好的锂离子电池隔膜,首先制备了单层静电纺聚偏氟乙烯六氟丙烯(P(VDF-HFP))纳米纤维,然后利用静电喷雾技术将Al2O3和ZrO2颗粒分散液均匀喷洒在其表面,再接收一层静电纺P(VDF-HFP)纳米纤维,制备出具有3层结构的有机/无机复合锂离子电池隔膜。同时制备了单层静电纺P(VDF-HFP)纳米纤维膜作为对比膜。考察了复合膜和对比膜的表面形貌、透气性、吸液率和热稳定性等物理性能,以及室温离子电导率、电化学稳定性和电池的循环充放电性能等电化学性能。结果表明:该复合膜的Gurley值为0.117S/(100mL?cm²),热收缩率为2.25%,吸液率为420%;室温下离子电导率为2.31mS/cm,电化学稳定窗口为5.4V,所制备电池首次放电比容量为138.6mA?h/g;在中间层添加纳米颗粒后,复合膜的透气性下降而其他指标均获得提升,综合性能优于相同条件下制备的单层静电纺隔膜 相似文献
9.
By reducing the energy and materials required to provide goods and services, nanotechnology has the potential to provide more appealing products while improving environmental performance and sustainability. Whether and how soon this potential could be realized depends on phrasing the right research and development (R&D) questions and pursuing commercialization intelligently. A sufficiently broad perspective at the outset is required to understand economic and technical feasibility, estimate life cycle environmental implications, and minimize unanticipated negative impacts. The rapid rise in federally funded nanotechnology R&D dictates that consideration of societal benefits will have a large role in setting the R&D agenda. We estimate potential selected economic and environmental impacts associated with the use of nanotechnology in the automotive industry. In particular, we project the material processing and fuel economy benefits associated with using a clay-polypropylene nanocomposite instead of steel or aluminum in light-duty vehicle body panels. Although the manufacturing cost is currently higher, a life cycle analysis shows potential benefits in reducing energy use and environment discharges by using a nanocomposite design. 相似文献
10.
Life cycle assessment of switchgrass- and corn stover-derived ethanol-fueled automobiles 总被引:1,自引:0,他引:1
Utilizing domestically produced cellulose-derived ethanol for the light-duty vehicle fleet can potentially improve the environmental performance and sustainability of the transport and energy sectors of the economy. A life cycle assessment model was developed to examine environmental implications of the production and use of ethanol in automobiles in Ontario, Canada. The results were compared to those of low-sulfur reformulated gasoline (RFG) in a functionally equivalent automobile. Two time frames were evaluated, one near-term (2010), which examines converting a dedicated energy crop (switchgrass) and an agricultural residue (corn stover) to ethanol; and one midterm (2020), which assumes technological improvements in the switchgrass-derived ethanol life cycle. Near-term results show that, compared to a RFG automobile, life cycle greenhouse gas (GHG) emissions are 57% lower for an E85-fueled automobile derived from switchgrass and 65% lower for ethanol from corn stover, on a grams of CO2 equivalent per kilometer basis. Corn stover ethanol exhibits slightly lower life cycle GHG emissions, primarily due to sharing emissions with grain production. Through projected improvements in crop and ethanol yields, results for the mid-term scenario show that GHG emissions could be 25-35% lower than those in 2010 and that, even with anticipated improvements in RFG automobiles, E85 automobiles could still achieve up to 70% lower GHG emissions across the life cycle. 相似文献
11.
We use life cycle assessment methodology to compare three disposal options for unused pharmaceuticals: (i) incineration after take-back to a pharmacy, (ii) wastewater treatment after toilet disposal, and (iii) landfilling or incineration after trash disposal. For each option, emissions of active pharmaceutical ingredients to the environment (API emissions) are estimated along with nine other types of emissions to air and water (non-API emissions). Under a scenario with 50% take-back to a pharmacy and 50% trash disposal, current API emissions are expected to be reduced by 93%. This is within 6% of a 100% trash disposal scenario, which achieves an 88% reduction. The 50% take-back scenario achieves a modest reduction in API emissions over a 100% trash scenario while increasing most non-API emissions by over 300%. If the 50% of unused pharmaceuticals not taken-back are toileted instead of trashed, all emissions increase relative to 100% trash disposal. Evidence suggests that 50% participation in take-back programs could be an upper bound. As a result, we recommend trash disposal for unused pharmaceuticals. A 100% trash disposal program would have similar API emissions to a take-back program with 50% participation, while also having significantly lower non-API emissions, lower financial costs, higher convenience, and higher compliance rates. 相似文献
12.
Life cycle assessment of Chinese shrimp farming systems targeted for export and domestic sales 总被引:1,自引:0,他引:1
We conducted surveys of six hatcheries and 18 farms for data inputs to complete a cradle-to-farm-gate life cycle assessment (LCA) to evaluate the environmental performance for intensive (for export markets in Chicago) and semi-intensive (for domestic markets in Shanghai) shrimp farming systems in Hainan Province, China. The relative contribution to overall environmental performance of processing and distribution to final markets were also evaluated from a cradle-to-destination-port perspective. Environmental impact categories included global warming, acidification, eutrophication, cumulative energy use, and biotic resource use. Our results indicated that intensive farming had significantly higher environmental impacts per unit production than semi-intensive farming in all impact categories. The grow-out stage contributed between 96.4% and 99.6% of the cradle-to-farm-gate impacts. These impacts were mainly caused by feed production, electricity use, and farm-level effluents. By averaging over intensive (15%) and semi-intensive (85%) farming systems, 1 metric ton (t) live-weight of shrimp production in China required 38.3 ± 4.3 GJ of energy, as well as 40.4 ± 1.7 t of net primary productivity, and generated 23.1 ± 2.6 kg of SO(2) equiv, 36.9 ± 4.3 kg of PO(4) equiv, and 3.1 ± 0.4 t of CO(2) equiv. Processing made a higher contribution to cradle-to-destination-port impacts than distribution of processed shrimp from farm gate to final markets in both supply chains. In 2008, the estimated total electricity consumption, energy consumption, and greenhouse gas emissions from Chinese white-leg shrimp production would be 1.1 billion kW·h, 49 million GJ, and 4 million metric tons, respectively. Improvements suggested for Chinese shrimp aquaculture include changes in feed composition, farm management, electricity-generating sources, and effluent treatment before discharge. Our results can be used to optimize market-oriented shrimp supply chains and promote more sustainable shrimp production and consumption. 相似文献
13.
为解决目前锂离子电池负极材料固有的体积膨胀问题,使用室温下呈液态的镓锡(GaSn)合金作为锂离子电池负极材料,通过静电纺丝法将液态GaSn合金束缚在纳米纤维内部以及纳米纤维的网络状结构中间,并组装成锂离子电池,对其结构和性能进行表征与分析.结果表明:液态GaSn合金可均匀地分散在碳纳米纤维中,同时GaSn合金由于超声空... 相似文献
14.
Life cycle assessment of an ionic liquid versus molecular solvents and their applications 总被引:1,自引:0,他引:1
Ionic liquids (ILs) have been claimed as "greener" replacements to molecular solvents. However, the environmental impacts of the life cycle phases and comparison with alternative methods have not been studied. Such a life cycle assessment (LCA) is essential before any legitimate claims of "greenness" can be made and is the subject of this paper. The model IL selected is 1-butyl-3-methyl-imidazolium tetrafluoroborate ([Bmim][BF4]) and its use as a solvent for the manufacture of cyclohexane and in a Diels-Alder reaction was assessed. These uses are compared with more conventional synthesis methods. The results indicate that processes that use IL are highly likely to have a larger life cycle environmental impact than more conventional methods. Sensitivity analysis shows that the result is robust to errors and variation in the data. For cyclohexane synthesis, the industrial gas phase process is the greenest, but the three solvents compared for the Diels-Alder reaction showed comparable life cycle impact. Although ILs are not the most attractive alternatives, the result may change if their separation efficiency, stability and recyclability are improved. Because there are many kinds of ILs, with many applications, two examples are not enough to reach any general conclusions about the greenness of all ILs. However, the life cycle data and approach of this study can be used for evaluating the greenness of more kinds of solvents, processes, and emerging technologies. 相似文献
15.
《Journal of dairy science》2022,105(7):5849-5869
To overcome the environmental challenges faced by the global agricultural sector while also ensuring economic viability, dairy farmers must improve the efficiency of their systems. To improve system efficiency, the performance of an average production system must be determined, as it establishes a benchmark from which the efficacy of proposed management practices and mitigation strategies can be assessed. Identified management practices and mitigation strategies can then be compiled to create ambitious but realistic targets for the sector to strive toward. Therefore the objective of this study was to calculate the environmental performance of an average spring-calving pasture-based dairy system and an ambitious target dairy system. Life cycle assessment (LCA) of 2 pasture-based dairy systems were conducted: (1) current average spring-calving pasture-based dairy system (current), and (2) a spring-calving pasture-based dairy system that has achieved key performance targets set by the most efficient dairy systems (target). An existing dairy LCA model was updated with country-specific emission factors, life cycle inventory data, and recommended methodologies. The environmental impact categories assessed were global warming potential, nonrenewable energy depletion, acidification potential, and eutrophication potential (marine and freshwater). Two functional units were used: per kilogram of fat- and protein-corrected milk (FPCM), and per hectare. To assess the effects of the model updates, the current dairy system was simulated twice, once with the previous version of the dairy LCA model, and second with the updated LCA model. The addition of country-specific emission factors, updated inventory data, and implementation of recommended methods has resulted in global warming potential and nonrenewable energy depletion being reduced by 10.4% and 10.9%, respectively. The updates had negligible effects on acidification and eutrophication potential. The inclusion of assumptions around carbon sequestration in grassland further reduced global warming potential by 16.4%. Moving from the current dairy system to the target dairy system was reported to reduce the environmental impact per kilogram of FPCM across all impact categories investigated. When expressed per hectare, transitioning toward the target dairy system reduced acidification, freshwater eutrophication, and nonrenewable energy depletion by 2.0%, 8.8%, and 13.8%, respectively. In contrast, transitioning toward the target dairy system increased global warming per hectare and, to a lesser degree, marine eutrophication potential per hectare. The increase in global warming and marine eutrophication potential per hectare was attributed to the increase in stocking rate and subsequently milk production per hectare (9,950 vs. 14,100 kg of FPCM/ha). This study demonstrates that the adoption of management practices that improve system efficiency will reduce the environmental impact per kilogram of FPCM and can contribute to the future sustainability of pasture-based dairy systems. However, improved system efficiency can be offset by the associated increase in productivity, highlighting the importance of reporting multiple environmental impact categories and functional units to prevent pollution swapping. New research and mitigation strategies will be required to improve the environmental sustainability of dairy systems beyond the target system in the future. 相似文献
16.
利用静电纺丝技术,通过改变转鼓转速,制备并复合形成三层自增强PAN纳米纤维复合隔膜。研究不同转鼓转速下所得中间层用PAN纳米纤维膜的排列及形貌特点,测试三层自增强PAN纳米纤维复合隔膜的物理力学性能及电化学性能,以评价其综合表现。结果表明:当中间层的转鼓转速为700 r/min时,制备的三层自增强PAN纳米纤维复合隔膜在纵向(即收集方向)的拉伸断裂强度达到最大,为13.10 MPa;室温下的孔隙率和吸液率分别为78.3%和356.3%,20℃下的离子电导率高达0.63 m S/cm,电化学稳定电压达到5.0 V,电化学稳定性优异;由其制备的锂离子电池拥有较高的首次放电比容量值,达138.4 m A·h/g。三层自增强PAN纳米纤维复合隔膜的综合性能能够满足锂离子电池的需要。 相似文献
17.
Climate change and water scarcity are important issues for today's power sector. To inform capacity expansion decisions, hybrid life cycle assessment is used to evaluate a reference design of a parabolic trough concentrating solar power (CSP) facility located in Daggett, CA, along four sustainability metrics: life cycle (LC) greenhouse gas (GHG) emissions, water consumption, cumulative energy demand (CED), and energy payback time (EPBT). This wet-cooled, 103 MW plant utilizes mined nitrates salts in its two-tank, thermal energy storage (TES) system. Design alternatives of dry-cooling, a thermocline TES, and synthetically derived nitrate salt are evaluated. During its LC, the reference CSP plant is estimated to emit 26 g of CO(2eq) per kWh, consume 4.7 L/kWh of water, and demand 0.40 MJ(eq)/kWh of energy, resulting in an EPBT of approximately 1 year. The dry-cooled alternative is estimated to reduce LC water consumption by 77% but increase LC GHG emissions and CED by 8%. Synthetic nitrate salts may increase LC GHG emissions by 52% compared to mined. Switching from two-tank to thermocline TES configuration reduces LC GHG emissions, most significantly for plants using synthetically derived nitrate salts. CSP can significantly reduce GHG emissions compared to fossil-fueled generation; however, dry-cooling may be required in many locations to minimize water consumption. 相似文献
18.
J.G. Usack L. Gerber Van Doren R. Posmanik J.W. Tester L.T. Angenent 《Journal of dairy science》2019,102(4):3630-3645
Anaerobic digestion coupled with combined heat and power production on dairy farms is environmentally advantageous; however, high capital and operating costs have limited its adoption, especially in the United States, where renewable electricity and heat production are under-incentivized. Biogas is also at a disadvantage because it has to compete with very low natural gas prices. The objective of this study was to evaluate the feasibility of integrating absorption refrigeration technology for combined cooling, heat, and power (CCHP) on the farm to help bridge this economic hurdle. A combined environmental life cycle and techno-economic assessment was used to compare 2 cooling pathways with and without co-digestion. We considered using CCHP to (1) displace electricity-driven refrigeration processes (e.g., milk chilling/refrigeration, biogas inlet cooling) or (2) mitigate heat stress in dairy cattle via conductive cow cooling. All cooling scenarios reduced environmental emissions compared with combined heat and power only, with an appreciable reduction in land use impacts when employing conductive cow cooling. However, none of the cooling scenarios achieved economically viability. When using cooling power to displace electricity-driven refrigeration processes, economic viability was constrained by low electricity prices and a lack of incentives in the United States. When used for conductive cow cooling, economic viability was constrained by (1) low waste heat-to-cooling conversion efficiency; (2) limited conductive cow cooling effectiveness (i.e., heat-stress mitigation); and (3) low heat stress frequency and limited severity. However, we predict that with minor improvements in conductive cow cooling effectiveness and in hotter climates, CCHP for conductive cow cooling would be economically viable even in current US energy markets. 相似文献
19.
Adewuyi YG 《Environmental science & technology》2005,39(10):3409-3420
Sonoprocessing is the utilization of sonic and ultrasonic waves in chemical synthesis and processes. It is a new and rapidly growing research field with broad applications in environmental engineering, green chemical synthesis, and processing. The application of this environmentally benign technique in environmental remediation is currently under active research and development. Sonochemical oxidation is effective in treating toxic effluents and reducing toxicity. However, the ultrasonic treatment is highly energy intensive since sonication is relatively inefficient with respect to total input energy and is therefore not economically attractive or feasible alone. Hence, sonochemistry has not yet received much attention as an alternative for industrial and large-scale chemical and environmental processes. One of the most interesting topics in the recent advances in sonochemistry is the possibility of double or more excitations with ultrasound and other types of energy. The coupling of ultrasound with other free energy sources (i.e., UV) or chemical oxidation utilizing H2O2, O3, or ferrous ion presents interesting and attractive approaches. Therefore, many recent efforts have been devoted to improving the efficiency of sonochemical reactions by exploiting the advantages of combinative or hybrid processes involving the simultaneous or sequential use of ultrasonic irradiation and other advanced oxidation processes, electrochemical processes, and biological treatment. This paper provides a critical review of the applications of ultrasound in environmental remediation, focusing on recent developments and unifying analysis of combinative or hybrid systems, namely, sonophotochemical oxidation processes. 相似文献
20.
Klaus Schneider Inga Ollroge Martin Clauberg Ulrike Schuhmacher-Wolz 《Food Additives & Contaminants》2007,24(7):768-776
Environmental contaminants originate from diverse sources and, owing to their ubiquitous presence in the environment, may appear in foods. Setting standards in food is increasingly important within the European Union and world-wide to protect consumers' health and to avoid trade barriers. This paper analyses how maximum levels for environmental contaminants in food were derived by the Codex Alimentarius Commission, by the European Union and by national authorities (USA, Germany). Both the risk assessment process (derivation of tolerable intake values and intake assessment by scientific bodies) and the risk management process (derivation of maximum levels by risk management bodies) are discussed. The various organizations show similar approaches and similar numerical values for maximum levels of the same contaminants in the same food items. In the area of decision-making for risk management, there was a noticeable lack of transparency in all the investigated systems. Recommendations are made for the development and harmonization of exposure assessment and communications between risk assessment and risk management processes, for improvements in documentation and for greater transparency within risk management decision-making processes. 相似文献