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Rotor and stator support structures of significant size and mass are required to withstand the considerable loads that direct-drive wind turbine electrical generators face to maintain an air-gap clearance that is open and stable. With the increase of scale, reducing the weight and environmental impact of these support structures is believed to be one of the key components to unlocking the true potential of direct-drive generators. An investigation on the electrical generator rotor structure of the IEA 15 MW offshore reference wind turbine was conducted. An integrated approach that considered the environmental impact, including the manufacturing energy usage and CO2 footprint, as well as the financial repercussions of structural parameter modifications as they are optimised was followed, making use of distinct commercial pieces of software. The rotor structure was parametrically optimised, and its operating loading conditions were evaluated at various size scales. The study determined that the effect of thermal loading is significant, which forces the designer to augment the mass to comply with the imposed structural requirements. The ensuing life-cycle assessment showed an increase in the environmental impact due to the consideration of this particular load, whose effect in structural deflection and stress has been typically underestimated. [ABSTRACT FROM AUTHOR]

From the design space explored for series architecture plug-in hybrid electric vehicle transit buses by the authors, one powertrain and control design is selected to provide maximum benefit to investment ratio. Sensitivity analysis is performed for this powertrain configuration. Vehicle parameters (including vehicle mass, coefficient of drag, coefficient of rolling resistance), usage parameters (drivecycle, annual vehicle miles traveled, number of recharges in a day, recharge current, and battery temperature), and economic parameters (fuel price, motor price, and battery price) are varied to understand their effect on the number of required battery replacements, net present value, payback period, and fuel consumption reduction. It is shown that battery temperature has the most significant impact, particularly on the number of battery replacements and net present value and, as such, must be well controlled in practice. It is shown that to maintain the battery at 20°C, for ambient temperatures between −5°C and 45°C, 0.8–1.8% excess fuel is required across all drivecycles for the considered plug-in hybrid electric vehicle transit bus powertrain configuration. In addition, the well-to-wheel emissions of criteria pollutants resulting from the usage of this plug-in hybrid electric vehicle transit bus in Indiana and California are calculated and compared with the conventional transit bus, using the GREET (Greenhouse Gases, Regulated Emissions and Energy Use in Transportation) Model. With a single over night charge, the plug-in hybrid electric vehicle transit bus operating in either Indiana or California produces 50% less CO2 and other greenhouse gases as compared to a conventional transit bus. [ABSTRACT FROM AUTHOR]

Promoting biodiesel industrialization is not only an important measure in addressing the energy crisis and global warming but is also a driver for industrial restructuring and rural development. To promote the development of the biofuel industry, the Chinese central government has set a target that biofuel will account for 15% of transport energy consumption by 2020. The macroeconomic impacts of this policy, however, are unknown. This paper estimates the economic and environmental impacts on Yunnan of meeting this target using a demand-driven input–output model for Jatropha curcas L. biodiesel. The study combines life-cycle analysis and input–output analysis to establish the industrial relationship of the biodiesel sector with other sectors. The results show that meeting the biofuel policy target in 2020 will generate 296,780 thousand job opportunities annually (man-year) and increase household income. Meeting this target will also lower carbon emission by 11.39 million tonnes of CO2 equivalent, valued at 2.41 billion Yuan. However, meeting the target will decrease tax revenue by 1.8 billion Yuan and reduce the provincial gross domestic product by 754.95 million Yuan. Thus, the industrialization of J. curcas L. biodiesel can contribute to the development of a green economy and is a positive response to the policies of energy conservation and emission reduction. The promotion of biodiesel production, however, requires a trade-off between economic and environmental targets. [ABSTRACT FROM AUTHOR]

Abstract China is the largest producer of aluminium globally. The energy consumption and greenhouse gas (GHG) emissions caused by primary aluminium and recycled aluminium production in China have aroused widespread concern. In this paper, the energy consumption and GHG emissions caused by primary aluminium and recycled aluminium production from a life-cycle perspective are estimated, and the comparative analysis between China and the U.S. are conducted. The results indicate that life-cycle fossil energy consumption and GHG emissions of primary aluminium are 144612 MJ/t and 14772.72 kg CO 2-eq /t respectively, which are about twice as much as that of the U.S. This is attributed to the high energy and GHG emissions intensities of electricity production which is dominated by coal generated electricity. The life-cycle energy consumption and GHG emissions of recycled aluminium production is only 6.37% and 4.45% of the primary aluminium. Recycled aluminium industry and low-carbon electricity used for aluminium electrolysis are worthy to be supported since they are beneficial for the life-cycle performance of aluminium. [ABSTRACT FROM AUTHOR]

Carbon emissions are derived mainly from the building, industrial, and transport sectors. Buildings are responsible for more than 40% of global energy use and for as much as 33% of global greenhouse gas emissions. By the end of 2016, 57.4% of the total population lived in urban areas in China, a dramatic increase from 26% in 1990. It is essential to study and analyze both energy consumption and carbon emissions of buildings. Taking Guangzhou city of China as an example, this study applied a hybrid life cycle assessment approach to quantify both the energy consumption and CO 2 emissions throughout the life cycle of an urban residential building. The data was collected from the Guangzhou input–output (IO) table of 2012, Guangzhou Statistical Yearbook of 2013, China Electric Power Yearbook of 2013, and statistical data of the studied building. Results showed that the overall life cycle energy consumption and CO 2 (eq.) emissions for the studied building, constructed in 2012, were approximately 72,591.98 GJ and 12,637.32 t, respectively. The largest CO 2 (eq.) emission factor was oil and the smallest one was electricity. The CO 2 emissions of steel, concrete, brick, and cement together accounted for 76.69% of the total emissions which are related to building materials in the preparation stage. This research not only promotes the construction of eco-cities or eco-communities, but also provides decision makers with comprehensive data on the energy consumption and environmental impacts of residential buildings. The findings are of considerable importance in terms of energy saving and emissions reductions for society as a whole. [ABSTRACT FROM AUTHOR]

Manual and automated blind controls are typically not included in energy and daylight simulation in part because there is no consensus in the research or practice communities about the way users operate manual blinds or override automated blinds. In order for blind use patterns to become part of energy and daylight simulation best practices, the range of annual energy and daylighting impacts associated with blind use must be understood. This paper addresses these aspects by comparing four leading candidates of manually-controlled blinds plus two automated blind control algorithms using a high-rise office building located in Boise, ID. This study revealed that all four current “manual” blind use algorithm choices perform relatively similarly to automated systems, and surprisingly sometimes even more efficiently. LM-83 currently has the lowest average occlusion during regularly occupied hours, followed by Lightswitch-2002, while Blindswith-A and -B have the highest average occlusion. The IES-recommended manual blind algorithm resulted even in lower average blind occlusion and lighting energy consumption than automated systems. Finally, life-cycle cost analysis was calculated. The results show that the cost savings from interior automated shading system are substantial over a 30-year time horizon, when compared with common passive manual blinds ($25 versus $7.6 Net Present Value per SF glazing area). [ABSTRACT FROM AUTHOR]

This study develops a bottom-up model to quantitatively assess the comprehensive effects of replacing traditional petroleum-powered vehicles with natural gas vehicles (NGVs) in China based on an investigation of the direct energy consumption and critical air pollutant (CAP) emission intensity, life-cycle energy use and greenhouse gas (GHG) emission intensity of NGV fleets. The results indicate that, on average, there are no net energy savings from replacing a traditional fuel vehicle with an NGV. Interestingly, an NGV results in significant reductions in direct CAP and life-cycle GHG emissions compared to those of a traditional fuel vehicle, ranging from 61% to 76% and 12% to 29%, respectively. Due to the increasing use of natural gas as a vehicle fuel in China (i.e. approximately 28.2 billion cubic metres of natural gas in 2015), the total petroleum substituted with natural gas was approximately 23.8 million tonnes (Mt), which generated a GHG emission reduction of 16.9 Mt of CO2 equivalent and a CAP emission reduction of 1.8 Mt in 2015. Given the significant contribution of NGVs, growing the NGV population in 2020 will further increase the petroleum substitution benefits and CAP and GHG emission reduction benefits by approximately 42.5 Mt of petroleum-based fuel, 3.1 Mt of CAPs and 28.0 Mt of GHGs. By 2030, these benefits will reach 81.5 Mt of traditional petroleum fuel, 5.6 Mt of CAPs and 50.5 Mt of GHGs, respectively. [ABSTRACT FROM AUTHOR]

An expandable electric vehicle (EV) life-cycle analysis (LCA) model (EV-LCA) is developed to analyze the life cycle (LC) energy consumption (EC) and greenhouse gas (GHG) emissions of EVs considering variations in electricity grid mix and vehicle energy efficiency performance. Employing EV-LCA as a common model platform, a case study is conducted to assess the LC GHG emissions of an average passenger battery electric vehicle (BEV) and plug-in hybrid electric vehicle (PHEV) with a comparative internal combustion engine vehicle (ICEV) under real-world driving conditions in China, the U.S., Japan, Canada and EU, based on country-specific data. The model is shown to be applicable and flexible to assess the average EC and GHG emissions performance of EVs at both regional and national level under large-scale adoption. The case study indicates that currently BEVs show a positive performance in GHG emissions reduction (GER) (ranging from 30% to 80%) when compared to gasoline ICEVs globally. It is also found that the GER effect of EV is highly variable geographically due to significant differences in the electricity grid mix and GHG emissions intensity of grid electricity among countries. EVs can achieve higher GER with the development of low carbon electricity in future. The GER potential of PHEV is significantly influenced by the all-electric range (AER). Several policy suggestions are presented, including the consideration of regional characteristics in GER assessment of EVs and the need to accelerate low-carbon electricity development. [ABSTRACT FROM AUTHOR]

China has become the global largest electric vehicle (EV) market, making the energy and climate issues of EV industry in terms of life cycle attract widespread attention. Based on the self-designed life-cycle analysis tool and up-to-date database, this study analyzes energy consumption and greenhouse gas (GHG) emissions of a typical passenger internal combustion engine vehicle (ICEV), and battery EV (BEV) and plug-in hybrid EV (PHEV) installed with different lithium-ion battery types, covering both fuel cycle and vehicle cycle. Owing to the battery installation, which shares nearly 30% of the GHG emissions in EV's vehicle cycle, the BEV and PHEV emit 13533–15445 kgCO 2 ,eq/vehicle and 11572–12186 kgCO 2 ,eq/vehicle, 65.6%–89.0% and 41.6%–49.1% higher than that of the ICEV, respectively. EV's fuel-cycle low emissions offset its surplus emissions in vehicle cycle. The EV generates 219.8–230.9 gCO 2 ,eq/km in life cycle, achieving 18.3%–22.6% of reduction compared to the ICEV. Development of non-fossil power will highlight the advantages of EVs in energy conservation and GHG emission reduction, e.g. if the proportion of coal power decreased to 10%, BEV's life-cycle GHG emissions will reduce about 70% than current level. Policies should focus on both EVs development acceleration and the low-carbon automotive and battery industry creation. • A life-cycle carbon footprint analysis model for passenger vehicles is built. • The database reflects up-to-date energy efficiency of China's automobile industry. • The vehicle-cycle GHG emissions of an EV are higher than a comparative ICEV. • The traction battery shares nearly half of a BEV's vehicle-cycle GHG emissions. • EVs' lower emissions in the fuel cycle offset their vehicle-cycle higher emissions. [ABSTRACT FROM AUTHOR]

Combined heat and power (CHP) plants are a great improvement over waste-to-energy incineration plants supplying only heat, and power plants supplying only electricity. The primary purpose of a functioning CHP plant however, may be to provide district heating services, and thereby its main output will be heat energy. This paper is a case study commissioned by Karlskoga Energi och Miljö AB (KEMAB in short; Karlskoga Energy and Environment) in the Värmland State of south-central Sweden, and focuses on the functioning of the CHP plant owned and operated by the company. The life-cycles of the fuels used by the CHP – household/industrial waste, bio-oil, light fuel oil, wood waste, wood chips, a slaughterhouse-waste-derived product and peat to generate 202,222 MWh of heat, 119,234 MWh of steam and 28,220 MWh of electricity have been studied, and the carbon footprint calculated for year-2016. Using two sets of emissions factors for the combustion stage of the life-cycle, as part of a data uncertainty analysis, the total emissions were 44,000 tonnes carbon dioxide equivalents (CO 2 -eq) and 58,000 tonnes CO 2 -eq respectively. A quasi-realistic scenario analysis in which plastics are not available for incineration and have to be substituted with alternatives has also been carried out, and while wood waste has been suggested as the best alternative with regard to greenhouse gas (GHG) emissions, availability permitting, a combination of alternatives has been mooted as the practical option. [ABSTRACT FROM AUTHOR]

The life-cycle analysis (LCA) is conducted with a combination of real-time fuel consumption rate data for diesel/liquefied natural gas (LNG) heavy-duty vehicles (HDVs) in China, actual provincial diesel/LNG HDV population data, and a life-cycle inventory database for the Tsinghua-LCA Model (TLCAM) specified for the context of China. The results indicate that direct energy consumption and the life-cycle energy use (MJ) of an LNG HDV are approximately 7.4% and 6.2% higher than that of a comparable diesel HDV, whereas an approximate 8.0% reduction in the life cycle of GHG emissions is estimated if diesel HDVs are replaced with LNG HDVs in China. Due to the increasing use of LNG as an HDV fuel in China (i.e., approximately 4.6 billion cubic metres of natural gas in 2015), the accumulated diesel fuel substituted with LNG was approximately 16 million tons, which generated a GHG emission reduction of 6 million tons of CO 2 equivalent in the HDV fleet from 2006 to 2015. Given that the HDV fleet contributed approximately 6.1% of all GHG emissions in China in 2015, growing the LNG HDV population can increase GHG emission reduction by an approximate range of 6.5–9.1 million tons of CO 2 equivalent by 2020. [ABSTRACT FROM AUTHOR]

An environmental impact assessment was obtained for sulfoaluminate clinker preparation from red mud, desulfurization gypsum, and other industrial solid wastes, and the results were compared with a standard production method. A quantitative analysis and prediction of the environmental burden that results from mining/waste utilization, energy consumption, and waste emissions in sulfoaluminate clinker preparations using limestone, gypsum, bauxite and using industrial solid wastes as raw materials was provided. The life cycle theory was used to analyze the different production technologies, and it was found that comprehensive waste utilization to produce sulfoaluminate clinker reduces resource consumption, global warming, chemical oxygen demand, particulate matter, primary energy consumption, acidification, eutrophication, and solid waste generation by 92.89%, 40.95%, 36.48%, 25.25%, 12.6%, 8.3%, 7.91%, and 5.29%, respectively, compared with the conventional preparation of sulfoaluminate clinker. The sulfoaluminate clinker production with comprehensive waste utilization can reduce the total environmental burden by 38.62% compared with the conventional process. Cement manufacturing enterprises should combine power plants and chemical plants for industrial solid waste collection and recycling. Such a production mode would promote a circular economy industry, reduce the consumption of primary energy and natural resources, and reduce global warming. [ABSTRACT FROM AUTHOR]

Three landfill gas (LFG) valorization technologies were compared using energy and exergy efficiency and a streamlined Life-Cycle Assessment (LCA) method. The technologies were (i) steam reforming and hydrogen utilization in an in situ cogeneration fuel cell (SR-IS-FCC), (ii) biogas utilization in an in situ gas engine cogeneration plant (IS-GEC), and (iii) amine scrubbing and biomethane utilization in an ex situ gas engine cogeneration plant (AS-ES-GEC). The SR-IS-FCC alternative recorded the highest exergy efficiency and savings in cumulative energy demand (CED), and the lowest global warming potential (GWP) when all the heat is utilized in situ; otherwise, the highest exergy efficiency and the lowest GWP and CED were associated with the AS-ES-GEC alternative. The results indicate that AS-ES-GEC is the preferential choice when heat cannot be utilized in situ. Otherwise, SR-IS-FCC records the best values for the three criteria, and the AS-ES-GEC technology is the least interesting alternative. [ABSTRACT FROM AUTHOR]

This paper examines the life-cycle inventory impacts on energy use and greenhouse gas (GHG) emissions as a result of candidate travelers adopting carsharing in US settings. Here, households residing in relatively dense urban neighborhoods with good access to transit and traveling relatively few miles in private vehicles (roughly 10% of the U.S. population) are considered candidates for carsharing. This analysis recognizes cradle-to-grave impacts of carsharing on vehicle ownership levels, travel distances, fleet fuel economy (partly due to faster turnover), parking demand (and associated infrastructure), and alternative modes. Results suggest that current carsharing members reduce their average individual transportation energy use and GHG emissions by approximately 51% upon joining a carsharing organization. Collectively, these individual-level effects translate to roughly 5% savings in all household transport-related energy use and GHG emissions in the U.S. These energy and emissions savings can be primarily attributed to mode shifts and avoided travel, followed by savings in parking infrastructure demands and fuel consumption. When indirect rebound effects are accounted for (assuming travel-cost savings is then spent on other goods and services), net savings are expected to be 3% across all U.S. households. [ABSTRACT FROM AUTHOR]

To meet the increasing market demand for store male calves sold in summer, cow-calf beef cattle producers from the Charolais area, France, can opt for various strategies including changing the calving period. The objective of our study was to analyze and compare the impacts on greenhouse gas emissions (GHG), energy consumption and land use of two grassland-based cow-calf beef systems in relation to their contrasted grassland management and animal production strategies. Based on repeated measurements over 2 years, we carried out a Life-Cycle Analysis on two systems designed on an experimental farm. The Aut-system was based on autumn-calvings that required budgeting for a sufficient quantity and quality of grass fodder stocks harvested to cover the high feed demands of winter-lactating cows. The Spr-system was based on spring-calvings so that the peak needs of the herd and the breeding cows coincided with peak pasture grazing period. Management of male calves relied on a more intensive use of concentrate in the Aut-system. This study showed that at identical beef live weight produced, the Spr-system required 18% more on-farm utilized agricultural area, excreted 14% more nitrogen and released 12% more enteric methane, but used 22% less mineral nitrogen fertilizer, 34% less fuel, 89% less off-farm fodder purchases, 73% less concentrate purchases and 5% less bedding straw purchases. Livestock emissions per animal were close between the two systems and accounted for 75% of gross GHG emissions. As the Aut-system had a higher animal productivity, it was able to dilute this impact at identical live weight produced (4% higher gross GHG emissions in the Spr-system). This higher productivity also enabled the Aut-system to use less land (13% higher land use in the Spr-system) but relied on greater use of inputs (31% lower energy consumption in the Spr-system). As the Aut-system involved a lower surface area to produce beef, it reduced the potential of carbon storage by grassland to offset gross GHG emissions. This is the reason why the Spr-system led to 9% lower net GHG emissions. This mixed bag of results raises the question of the relative weight lent to each environmental impact and of the complementarities between strategies in grassland-based systems at region-wide scale. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) reduction in China's iron and steel industry (CISI), which is responsible for more than 50% of global steel production, is essential for China's efforts to meet its carbon neutrality target. As one of the few options to achieve ultra-low GHG emissions in CISI, the GHG reduction benefits of hydrogen-based direct reduction (H-DR) are important. In this study, an life cycle (LC) assessment model in the CISI context is developed and various technology route are analyzed under a unified framework, combining hydrogen supply chain (HSC) modeling, actual data from steel plants and DR demonstration projects. The results show that under ideal HSC, compared with LC GHG emission of conventional route (2389.5 kgCO 2,eq /t), hydrogen-enriched conventional route can achieve 10% GHG reduction, and if NG is used for H-DR heat supply, only 43.4% emission reduction could be achieved; if only pure hydrogen is used in H-DR, the GHG of H-DR would be close to that of scrap-electric arc furnace pathway (904.6kgCO 2,eq /t) currently in China. The GHG emissions level of HSC lower than 200gCO 2,eq /MJ can safeguard that the H-DR route comparable to BF-BOF route. H-DR can be rolled out across China to achieve emissions reductions only when both the HSC and electricity have low GHG emissions; both the hydrogen-enriched conventional route and the fossil fuel-based DR route can be used as transitional technologies then. In addition, this study examines the impact of analysis methods on the fairness of GHG accounting. • Integral life cycle GHG emission analysis of hydrogen supply chain and hydrogen-based steelmaking pathways in China. • Comparison of conventional pathways, fossil fuel-based and hydrogen-based steelmaking pathways in a unified life cycle analysis framework. • The impact of GHG analyzing method and system boundary on the equity of technology routes and plants is explored. [ABSTRACT FROM AUTHOR]

Because of increasing environmental and energy security concerns, a detailed understanding of energy efficiency and greenhouse gas (GHG) emissions in the petroleum refining industry is critical for fair and equitable energy and environmental policies. To date, this has proved challenging due in part to the complex nature and variability within refineries. In an effort to simplify energy and emissions refinery analysis, we delineated LP modeling results from 60 large refineries from the US and EU into broad categories based on crude density (API gravity) and heavy product (HP) yields. Product-specific efficiencies and process fuel shares derived from this study were incorporated in Argonne National Laboratory’s GREET life-cycle model, along with regional upstream GHG intensities of crude, natural gas and electricity specific to the US and EU regions. The modeling results suggest that refineries that process relatively heavier crude inputs and have lower yields of HPs generally have lower energy efficiencies and higher GHG emissions than refineries that run lighter crudes with lower yields of HPs. The former types of refineries tend to utilize energy-intensive units which are significant consumers of utilities (heat and electricity) and hydrogen. Among the three groups of refineries studied, the major difference in the energy intensities is due to the amount of purchased natural gas for utilities and hydrogen, while the sum of refinery feed inputs are generally constant. These results highlight the GHG emissions cost a refiner pays to process deep into the barrel to produce more of the desirable fuels with low carbon to hydrogen ratio. [ABSTRACT FROM AUTHOR]

This study deals with the investigation into optimum insulation thickness of installed inside building pipe network of VRF (variable refrigerant flow) systems. Optimum insulation thickness, energy savings over a lifetime of 10 years and payback periods are determined for high pressure gas pipelines, low pressure gas pipelines and low pressure liquid pipelines under the heating-only and cooling-only modes of the three-pipe VRF system using R-410A as refrigerant. By using the P 1 –P 2 method, the value of the amount of the net energy savings is calculated. Under heating mode of VRF system, while the optimum insulation thickness varies between 16 and 20 mm depending on the pipe sections of high pressure gas pipeline, it varies from 11 to 13 mm for the pipe sections of low pressure liquid pipeline. Under cooling mode of VRF system, the optimum insulation thickness varies between 7 and 8 mm for pipe sections of low pressure gas pipeline and low pressure liquid pipeline. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive literature review and a full process-based life-cycle analysis (LCA) of three types of batteries, viz., (1) valve-regulated lead-acid (VRLA), (2) flow-assisted nickel–zinc (NiZn), and (3) non-flow manganese dioxide–zinc (MnO 2 /Zn) for stationary-grid applications. We used the Ecoinvent life-cycle inventory (LCI) databases for the VRLA battery, coupled with inventory data from the CUNY Energy Institute (EI) for the NiZn and MnO 2 /Zn batteries under development there. In doing so, two indicators were tracked: the cumulative energy demand (CED) and global warming potential (GWP) of the upstream processes for producing, manufacturing, and transporting the finished product, as well as the effects of end-of-life impacts. We conducted a normalization of CED and GWP according to Wh of battery capacity to illustrate the effects of discharge rate on this commonly reported metric. We subsequently normalized according to the cumulative kWh of electricity throughput (kWh throughput ) to account for cycle life and efficiency data. This was done considering slow- and fast-discharge parameters for PbA chemistry and for current- and projected- parameters for the NiZn and MnO 2 /Zn chemistries to examine all possible effects. Additionally, the effects of recycle content on reducing CED and GWP were considered. Discharge rate was seen to have a significant effect for the VRLA system, with impacts over 41–46% higher in terms of CED and GWP at the 2-h discharge time, versus an 8-h discharge time, when considering the entire life cycle (kWh throughput normalization). With kWh throughput normalization, the NiZn- chemistry under development has lower CED and GWP than PbA-VRLA batteries for both current and projected targets of round-trip efficiency and cycle life. MnO 2 /Zn performs poorer than VRLA currently (41–52% higher CED and 35–38% higher GWP), but performs significantly better than VRLA when using projected targets (43% lower CED and 47% lower GWP). The energy requirement for battery production and transport is most significant for PbA and MnO 2 /Zn batteries. This is the case for PbA due to its relatively short service life– and this battery was found to be most sensitive to changes in battery service life and efficiency. For MnO 2 /Zn this was a result of low specific energy. [ABSTRACT FROM AUTHOR]

The United States consumes 22% of the entire world's energy which is equivalent to all of Europe and the entire continent of Africa combined. Residential homes, accounting for 23% of this consumption, are increasing in size while the average number of occupants is declining. Heating ventilation and air conditioning consume much of the energy in the home. The research team investigated a production homebuilder in the Midwest that builds twenty five models that range from 1041 square foot to nearly 3,000 square foot that was consistently achieving Home Energy Rating System (HERS) below 60. The purpose of this investigation was to determine those features contributing to these low ratings with maintaining competitive production housing pricing. The objectives of the research investigation are as follows: 1. To select a representative energy efficient model for analysis and determine those features that contribute to the energy efficiency; 2. To analyze the cost and energy savings of discrete groupings of features; and 3. To conduct a life cycle analysis on the initial cost and the energy saving of discrete feature. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel membrane energy exchanger that uses a liquid desiccant (RAMEE) is simulated in the HVAC system of a hospital in 4 North American climates. [•] Annual heating and cooling energy are reduced by up to nearly 70% and 20% respectively due to the RAMEE. [•] The RAMEE allows the capacity of the heating and cooling systems to be reduced by nearly 50% and 25% respectively. [•] The payback period for the RAMEE is 0–3 years. [•] The RAMEE reduces greenhouse gas emission (CO2-equivalent) by up to 25%. [ABSTRACT FROM AUTHOR]

Introduction. The cultivation of high-value fruit species is a profitable agricultural activity in many tropical countries; however, intensive fruit cultivation may depend on high amounts of external inputs. The objective of our study was to quantify and compare the resource use during the cultivation of eight tropical fruit species (Rubus glaucus, Solanum quitoense, Passiflora edulis, Cyphomandra betacea, Physalis peruviana, Ananas comosus, Persea americana and Mangifera indica) commonly cultivated in Colombia. It further aimed to identify greenhouse gas (GHG) emissions in the selected production systems and to highlight the potential to contribute to climate change mitigation efforts. Materials and methods. The analysis was based on data from agricultural databases and applied a life-cycle assessment with energy use and GHG emissions as impact categories. Furthermore, economic indicators were taken into account with the aim of integrating the environmental and economic goals of production systems. Results and discussion. Among the eight fruit species studied, mango (Mangifera indica) was found to have the lowest and tree tomato (Cyphomandra betacea) the highest emission profile. The variability in resource use among growers of the same species was high, indicating the need to improve management abilities at the farm level. Mineral fertilizer production was the highest contributor to GHG emissions. GHG- and energy-efficient management alternatives would have a high potential to reduce the carbon footprint of fruit cultivation. [ABSTRACT FROM AUTHOR]

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Abstract: Life-cycle fossil primary energy consumption (FPEC) and greenhouse gas (GHG) emission intensity of nine types of dominant secondary energy (SE) pathways for China in 2010 are calculated with iterative methods, using the TLCAM (Tsinghua Life-cycle Analysis Model). Three major types of GHG (CO2, CH4 and N2O) are considered for GHG emission intensity, and non-combustion CH4 leakage during the feedstock production sub-stage is included. We found the following. (1) Life-cycle FPEC intensities in units of per MJ SE are obtained and used, in order of magnitude, for: raw coal (recovered only); raw natural gas (NG, recovered and processed only); raw oil (recovered and processed); final coal (finally transported to end-user); final NG (finally transported to end-user); diesel; gasoline; residual oil and electricity. (2) Although their upstream GHG emission intensities are small, their life-cycle intensities are 103.5, 68.3, 81.6, 99.3, 70.0, 101.6, 91.7, 93.5 and 226.4 g CO2,e/MJ SE, respectively, when direct GHG emissions are included. (3) Life-cycle intensities of both FPEC and GHG emissions for SE in China are higher than those in some other countries, because of the relatively low overall efficiency and high percentage of coal in the national energy mix. [Copyright &y& Elsevier]

Enzymes and yeast are important ingredients in the production of ethanol, yet the energy consumption and emissions associated with their production are often excluded from life-cycle analyses of ethanol. We provide new estimates for the energy consumed and greenhouse gases (GHGs) emitted during enzyme and yeast manufacture, including contributions from key ingredients such as starch, glucose, and molasses. We incorporated these data into Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model and observed that enzymes and yeast together contribute 1.4 and 27 % of farm-to-pump GHG emissions for corn and cellulosic ethanol, respectively. Over the course of the entire corn ethanol life cycle, yeast and enzymes contribute a negligible amount of GHG emissions, but increase GHG emissions from the cellulosic ethanol life cycle by 5.6 g COe/MJ. [ABSTRACT FROM AUTHOR]

Abstract: Warm asphalt mixtures have been used worldwide aiming at saving energy and reducing emissions throughout the production process, without decreasing the in-service performance. This has been achieved with wax additives, chemical additives and foaming techniques. Benefits and drawbacks are mentioned in the literature for each process. This paper is a review of the main aspects involved in WMA technology, including constituent materials, mix design and mechanical performance issues, as well as technological specificities. Some discussion associated to life-cycle analysis is also considered. In the view of the literature review, it can be stated that WMA is a very interesting technology, able to contribute to achieve environmental objectives along with acceptable performance. WMA processes themselves require some additional complexity that must be considered by the players involved. [Copyright &y& Elsevier]

Abstract: The paper deals with the development of a tool used for the life cycle assessment of residential buildings located in three different European towns: Brussels (Belgium), Coimbra (Portugal) and Luleå (Sweden). The basic tool focuses on the structure and the materials of the buildings and permits the evaluation of the Embodied energy, Embodied carbon and yearly energy consumption. For that purpose, a different set of original data is taken into account for each location, in which the monthly temperatures, energy mix, heating and cooling systems are defined. The energy consumption, being for heating space or water, for cooling or for lighting is transformed into CO2 emissions to deduce the Operational carbon as well. The influence of the energy mix can therefore be assessed in the basic tool. As a matter of fact, the heating and cooling systems habitually used in the three countries are also of great importance. The District Heating system, is, for instance, incorporated in the basic tool. The presence of solar water heater or photovoltaic panels is also strongly influencing the operational carbon. After a short literature review on building LCA and the description of the basic tool, the software Pleiades + Comfie combined with Equer is used to achieve the complete LCA for one building using two different load bearing frames. The results of the calculations for Brussels climate are verified against these software results. The dependence of the results to parameters such as climate, energy mix and habits is then discussed in the companion paper. [Copyright &y& Elsevier]

Abstract: Fossil energy consumption (FEC) and greenhouse gas (GHG) emission intensities of major alternative vehicle fuels (AVFs) in China are calculated and compared with conventional fuels by means of full life-cycle analysis. Currently most of the AVFs have not relatively obvious GHG emission reduction when compared to the gasoline pathway: (1) coal-based AVF has higher intensities in terms of both the FEC and GHG emissions; (2) electricity from the average Chinese grid has the GHG emission intensity similar to that of gasoline pathway although relatively lower FEC intensity; and (3) first generation technology bio-fuel has relatively lower GHG emission intensity and substantially lower FEC intensity. It is forecasted that by 2020 when still comparing to the gasoline pathway: (1) coal-based AVF will still have FEC and GHG emission intensities that are 1.5–1.8 and 1.8–2.5 time those of gasoline pathway, and the application of carbon capture and storage technology can reduce the GHG emission intensity of coal-based AVF; (2) electricity will have significantly lower GHG intensity; and (3) second generation technology bio-fuel will have near zero FEC and GHG intensities. [Copyright &y& Elsevier]

During the past 2 years, high-speed rail (HSR) has become a popular concept in the United States partially because of its perceived environmental benefits. Many states are competing for HSR funding after the federal government made HSR a domestic priority. Of course, the allocation of funding is subject to many constraints. Among them, one of the necessary considerations should be the environmental efficiency of each HSR line. Using the proposed lines in California (CAHSR) and Florida (FLHSR) as examples, this article details a method that can be used to assess the life-cycle energy usage and carbon emission efficiency for new HSR lines. Ridership is forecasted based on data from existing HSR lines, and energy and emissions are analysed with the Economic Input–Output–Life-Cycle Analysis tool. Calculation shows that the construction of CAHSR is more environmentally efficient primarily due to its higher ridership predictions. [ABSTRACT FROM PUBLISHER]

Abstract: The Well-to-Meter (WTM) analysis module in the Tsinghua-CA3EM model has been used to examine the primary fossil energy consumption (PFEC) and greenhouse gas (GHG) emissions for electricity generation and supply in China. The results show that (1) the WTM PFEC and GHG emission intensities for the 2007 Chinese electricity mix are 3.247MJ/MJ and 297.688g carbon dioxide of equivalent (gCO2, e )/MJ, respectively; (2) power generation is the main contributing sub-stage; (3) the coal-power pathway is the only major contributor of PFEC (96.23%) and GHG emissions (97.08%) in the 2007 mix; and (4) GHG emissions intensity in 2020 will be reduced to 220.470gCO2, e /MJ with the development of nuclear and renewable energy and to 169.014gCO2, e /MJ if carbon dioxide capture and storage (CCS) technology is employed. It is concluded that (1) the current high levels of PFEC and GHG emission for electricity in China are largely due to the dominant role of coal in the power-generation sector and the relatively low efficiencies during all the sub-stages from resource extraction to final energy consumption and (2) the development of nuclear and renewable energy as well as low carbon technologies such as CCS can significantly reduce GHG emissions from electricity. [ABSTRACT FROM AUTHOR]

Abstract: Carbon fiber reinforced plastic is applied to railway car bodies to lighten them and reduce fuel consumption. This study looks at recycling methods for carbon fiber reinforced plastic used in a car body of a tilting train. It looks at four types of recycling: acid, pyrolysis in oxygen and nitrogen, organic solvents and supercritical process under various operating conditions. It evaluates the environmental performance of the recycling methods in terms of footprints of energy consumption and greenhouse gas emissions. A simplified life-cycle analysis is applied focusing mainly on the recycling treatment system. Only acid and pyrolysis in oxygen were capable of passing the technical and recyclate quality criteria. The energy footprint by pyrolysis in oxygen is approximately six times greater than acids and greenhouse gas emissions are some five times greater than with the acid recycling method. [Copyright &y& Elsevier]

Plug-in hybrid vehicles (PHEVs) are gaining attention over the world due to their ability to reduce gasoline/diesel consumption by using electricity from the grid. Despite the efforts of Society of Automotive Engineers Recommended Practice SAE J1711, it has not yet been established a worldwide methodology for calculation of fuel consumption and emission factors when regarding emission standards, with distinct driving cycles. This paper intends to contribute to the creation of this broader methodology, based on SAE J1711, aiming a fair comparison among vehicle technologies, and giving insight on electric grid impact and on CO2 life-cycle emissions. The methodology was applied to two simulated PHEVs exploring two different powertrain configurations: series and parallel; different driving cycles: CAFE, FTP75, NEDC and JC08; different driving distances (specially analyzing the average commuting daily distance of 20km) and different user behaviours regarding battery recharging. CO2 emissions were calculated for fuel consumption, electricity generation and cradle-to-grave. Electric grid power demand was estimated. Maintenance, manufacturer and use costs were discussed. [Copyright &y& Elsevier]

Abstract: Environmental quality has become increasingly affected by the built environment—as ultimately, buildings are responsible for the bulk of energy consumption and resultant atmospheric emissions in many countries. In recognizing this trend, research into building energy-efficiency has focused mainly on the energy required for a building''s ongoing use, while the energy “embodied” in its production is often overlooked. Such an approach has led in recent years to strategies which improve a building''s thermal performance, but which rely on high embodied-energy (EE) materials and products. Although assessment methods and databases have developed in recent years, the actual EE intensity for a given material may be highly dependent on local technologies and transportation distances. The objective of this study is to identify building materials which may optimize a building''s energy requirements over its entire life cycle, by analyzing both embodied and operational energy consumption in a climatically responsive building in the Negev desert region of southern Israel—comparing its actual material composition with a number of possible alternatives. It was found that the embodied energy of the building accounts for some 60% of the overall life-cycle energy consumption, which could be reduced significantly by using “alternative” wall infill materials. The cumulative energy saved over a 50-year life cycle by this material substitution is on the order of 20%. While the studied wall systems (mass, insulation and finish materials) represent a significant portion of the initial EE of the building, the concrete structure (columns, beams, floor and ceiling slabs) on average constitutes about 50% of the building''s pre-use phase energy. [Copyright &y& Elsevier]

A cost-benefit analysis of the AirCare program in the province of British Columbia on the basis of emissions cost factors from the literature showed a benefit outweighing the cost. Furthermore, a cost-effectiveness analysis comparing the AirCare program with a hybrid-car rebate program revealed that the AirCare program is more effective in reducing emissions of major air pollutants such as NOx, hydrocarbons, and CO. However, the hybrid-car rebate program contributes significantly to the reduction of greenhouse gas emissions because of much greater fuel efficiency, although its contribution to reducing emissions of major air pollutants is small compared with that of the AirCare program. Both the AirCare program and the hybrid-car program are therefore essential to addressing both local air quality improvement and global warming issues, and the programs complement each other. [ABSTRACT FROM AUTHOR]

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Previous life-cycle studies of buildings tended to omit the phases after demolition. If recycling is not included, the potential benefits of recycling are not possible to assess. A parametric study of a one family house is presented which focuses on the potential energy savings by recycling the various building materials after demolition. The results indicate that it can be more important to design a building for recycling than to use materials which require little energy for production, that the creation of effective recycling depends upon its consideration and inclusion at the design stage, that the re-use and adaptation of existing foundations is an important component of recycling. Le concept d'analyse de l'énergie du cycle de vie (LCEA) est employé pour formuler en valeurs d'énergie les flux des produits durant chaque phase du cycle de vie d'une activité. Dans le cas des constructions résidentielles, cela comprend d'habitude l'énergie consommée lors de la fabrication des matériaux de construction, l'énergie employée pour les opérations de la construction elle-même et celle dépensée pour la maintenance périodique. Pour positionner ces quantite s d'énergie dans un contexte national, il faut également prendre en considération l'énergie nécessaire aux autres marchandises et services consommés par les propriétaires. Cet article utilise le concept LCEA pour démontrer la nécessité de prendre en compte non seulement l'énergie de cycle de vie de la construction mais aussi l'énergie de cycle de vie attributable aux autres activités entreprises par les utilisateurs réels du bâtiment. L'énergie du cycle de vie d'un bâtiment résidentiel australien ainsi que les activités ordinaires des ménages sont analysées et simulées au cours d'une période de 30 ans en employant un exemple basé sur une portion jumeleacute;e à deux chambres à coucher et à revêtement de brique. Les implications à long terme montrent bien l'importance de prendre en compte l'énergie ne cessaire à la construction initiale d'un bâtiment résidentiel aussi bien que celle résultant de la consommation de marchandises et de services par les propriétaires. Afin d'encourager de façon durable ces pratiques, il est suggéré que les architectes prennent davantage en considération les activités des propriétaires lorsqu'ils conçoivent des bâtiments résidentiels, particulièrement en zone de climat tempéré. La conclusion de l'article fait le point des futurs secteurs de recherche du concept LCEA dans le domaine résidentiel. [ABSTRACT FROM AUTHOR]

The buildings sector contributes 20% of global greenhouse gas emissions, and building energy use is anticipated to double by 2050. Building performance research has typically focused on the operational phase, with life-cycle impacts increasingly studied, but often in isolation. This paper presents a novel framework integrating building energy modelling with life-cycle analysis and life-cycle costing. This is applied to four façade glazing materials in a 15-story case study office building in Queensland, Australia – a sub-tropical and commercial example rare in literature but important for future building development. Results demonstrate that double-glazed low-emissivity material (Type 4) was the most energy and financially efficient despite higher embodied energy and carbon than alternatives. It yielded operational energy and greenhouse gas emission savings of 13% against the baseline, and 2% lifetime financial savings. Clear double-glazing (Type 3) had the poorest overall performance, attributed to its low U-value trapping heat within the building and increasing net energy and emissions. This was new evidence that clear double-glazing should be carefully considered in sub-tropical climates. The integrated approach identified a material with improved overall performance. If only embodied impacts (production, transport, disposal) were assessed, GT1 would appear the best option as it takes less energy and carbon to manufacture and transport yet has very poor operational performance. This paper extends existing knowledge on façade materials and will aid future work on sustainable, low-emission building design in other climates, economies, designs and industries. • Integrated modelling of building façade operational energy, carbon, and cost. • Double-glazed low emissivity option reduced energy 13% in operational phase. • Rare commercial study in sub-tropical climate shows glazing selection influence. • One glazing type performed poorly in winter due to overnight 'heat trapping. • Framework will aid analysis for other climates, economies, designs and industries. [ABSTRACT FROM AUTHOR]

• The ARwet, ARdry and ARtb technologies are effective paving materials. • AR performs generally better than conventional AC with the same blend of aggregate. • The reuse of rubber from end-of-life tyres leads to significant benefits. • Direct costs of AR are 20–30% higher than direct costs of a conventional AC. • AR enhances paving resistance and respects environmental demands. Crumb rubber (CR) from end-of-life tyres has been used for several decades to improve asphalt mixtures properties. Three main processes of adding CR have been applied to produce asphalt rubber (AR) mixtures: the wet process, the dry process and the terminal blend process. This paper reviews the state of the practice of AR mixes in pavement technology, presenting some benefits and challenges of these paving materials. The paper presents the evolution of AR mixtures used as well as a discussion on the performance of AR solutions and on life-cycle assessment and emissions, energy consumption and costs, contributing to circular economy. [ABSTRACT FROM AUTHOR]