Search

This paper investigates the impact of periodic hull cleaning on oil tankers' energy efficiency using real 2012–2016 fleet performance and weather data extracted from noon reports for a fleet of eight identical Aframax-size crude oil tankers. The impact of changes in fuel consumption is estimated around the discontinuity when a vessel is cleaned and rely on both before-after and difference-in-differences estimators. The main results show that (i) periodic hull cleaning leads to a significant reduction in the daily fuel consumption; (ii) dry-docking leads to greater and significantly different reductions in fuel consumption than underwater hull cleaning, approximately −17% versus −9%; (iii) hull cleaning energy efficiency effect is greater when the vessel is sailing laden rather than in the ballast condition. These findings represent a key building block for the optimization of maintenance intervals. [ABSTRACT FROM AUTHOR]

With the rapid development of renewable energy, the proportion of wind power in power supply has grown significantly. Also, it influences the power price fluctuation. Since the marginal cost of wind power is almost zero, the growth of wind power's penetration rate has led to a crowding-out effect and challenged traditional power generation technology, substantially reducing the power price in the market. In perfect competition market, the real-time balance between supply and demand of power is regulated by the real-time power price fluctuation. So this paper models the intermittence of wind power as uncertain supply, and develops a capacity-investment model under the uncertainties of both supply and demand. We introduce priority dispatch elasticity to describe the crowding-out effect and take the power price to be endogenous in order to model the situation of high penetration rate. We compare the optimal wind power capacity decision under the strategy of priority grid connection and abandoned power management. Our results show that optimal capacity investment is inversely related to priority dispatch elasticity under both strategies. However, the profit from power generation is always higher when adopting the abandoned power management strategy. [ABSTRACT FROM AUTHOR]

Currently, the iron and steel industry (ISI) accounts for more than 16% of China's total energy consumption. Improving energy efficiency (EE) and promoting energy savings in this industry have vital significance for China's further sustainable development. Using provincial panel data from 2000 to 2014 and meta-frontier data envelopment analysis (DEA), this paper investigates EE and the energy-saving potential (EP) of China's ISI by considering regional technology heterogeneities. The results show that (1) from 2001 to 2014, EE in China's ISI achieved significant improvement. Technological progress is the most powerful driving factor, while the declines in scale efficiency and pure technical efficiency are two obstructive factors; (2) the sources of energy inefficiency (EI) show distinct spatial difference characteristics. EI in the eastern region mainly stems from scale inefficiency and pure technical inefficiency, while that in the central and western regions stems from three aspects of scale inefficiency, pure technical inefficiency, and technology gap; and (3) there is considerable EP in China's ISI, which represents nearly 80% of ISI's current total energy consumption. Because the sources of EP vary across regions, the focus of future work for China's regional ISI should also vary. [ABSTRACT FROM AUTHOR]

Water and energy are essential requirements for mineral processing plants, and they can be either scarce or expensive. In the present paper, the implications of a remote water source location (typically the seashore) are analyzed in terms of a definition for the combined water and energy operational cost required to transport ore concentrate using long distance pipelines. A typical process route is defined to expose the relevance of key process variables, including source remoteness and water reclamation both from tailing storage facilities and thickeners. Both mass and energy balances have been made to give an estimation of specific energy consumptions for a typical large scale Chilean mineral processing operations, considering a number of realistic hydraulic design criteria to make a comparative analysis of different plant processing capacities. In the present cost function definition, an account has been made on whether the water is either makeup or has been recirculated on the plant, and a distinction has been made on whether tailings are conventional or thickened, which allowed to analyze the relevance of in-plant water recovery compared to water recovery from the tailing disposal site. This has allowed to express the cost of water in terms of the various energy cost terms, thus showing in this case that the cost of water is ultimately the cost of energy, and therefore all cost components become proportional to the unit cost of energy. A piecewise constant pipeline diameter analysis scheme has been defined to allow studying the implications of water recovery on widely different plant sizes. Results show that for fixed water recovery rates, increasing plant throughput tends to cause a decrease on the specific energy for water transport. On the other hand, for fixed pipeline diameters, increasing the throughput causes an increase on the specific energy consumption, but such increase rate becomes milder at higher throughput rates. This suggests the advantage of the existence of common makeup water supply systems for mining districts with more than one mineral processing plant. On the other hand, for constant pipeline diameters, increasing the water recovery from the tailing disposal site or from thickeners generates a decrease of water specific energy consumption, where in the case of the water recovery from the tailing disposal site such decrease rate becomes stronger with the amount of water recovered. Results also shows that, except for very high solid concentrations, water makeup costs dominate over recirculation ones, supporting that producing thickened tailings is a more efficient option than conventional ones in the sense of specific energy consumption, in spite of the additional energy costs due to slurry transport that this option implies. [ABSTRACT FROM AUTHOR]

In order to achieve the targets underlined in the European Strategy for climate change and energy efficiency, the so called 20-20-20 package, the European Commission launched the Covenant of Mayors to endorse and support the efforts deployed by local authorities in the implementation of sustainable energy plans, and at the same time contribute to greenhouse gases emissions mitigation. This paper explores how the Covenant of Mayors (CoM) has been adopted in Portugal, and which type of measures are being defined and implemented by the municipalities. For that, all Sustainable Energy Action Plan (SEAP) submitted by Portuguese municipalities (124) have been examined, for which a detailed analysis was performed, including the Baseline Emission Inventory (70, i.e., around 50%). The municipalities that submitted SEAP cover 60% of the total population of the country because the main urban centres are a part of the 30% that have signed the CoM. Most common measures are related with changes on behaviour and infrastructure related to energy (such as renewable energies, energy efficiency in buildings, public lighting, etc.), waste and transport (for example optimization of: transport infrastructures, used vehicles and road operations). Public lighting is one of the energy measures present in all submitted SEAP, which plays a key role in energy consumption, reaching values of upwards of 12%, particularly in coastal areas due to higher population density and urban residential areas. Besides all efforts there is still a long way to go in terms of energy consumption reduction at local level. [ABSTRACT FROM AUTHOR]

The transition towards low-carbon economy requires a number of specific actions by a multiplicity of actors in order to reduce greenhouse gas (GHG) emissions, entailing energy efficiency, production of energy from renewable resources as well as the diffusion of more sustainable production and consumption patterns. Among the actors, local authorities can play a leading role for climate action. However, properly accounting for GHG emissions at local scale and identifying actions for GHG reduction are still an open challenge in many contexts. In this paper, we propose a method for GHG emissions accounting to support the identification of proper actions to achieve GHG reduction targets. The method widens the classical production-based approach to accounting, by proposing an extension of the accounting to three main areas: waste management and recycling, consumption patterns, and local land management. Life cycle thinking is applied as methodological basis for such extension. To illustrate the benefit of the proposed approach, the method has been applied to 16 municipalities (in Northern Italy), which were signatories of the Covenant of Mayors (CoM) initiative. CoM is a European initiative by which local authorities voluntarily commit to reduce their GHG emissions through the implementation of Sustainable Energy Action Plans. A comparison of the emission profile of the different municipalities helps identifying common patterns and local peculiarities to be addressed to achieve the reduction target. For the analysed case studies, the biggest contribution to GHG emissions comes from the consumption of the natural gas and electricity by the household sector. Emissions from waste generation play a minor role in the selected case studies. However, the inclusion of avoided emissions coming from waste recycling highlights the reduction potential if an appropriate waste management system is in place. Consumption patterns, as well, may play a relevant role. For example, assessing GHG emissions related to food consumption on top of those due to other drivers, the total municipal emissions change by increasing for an average of 22.6% for the selected case studies. Moreover, local land use planning and management should be included in the assessment, being crucial not only for the emissions uptake but also for climate mitigation and adaptation. The proposed approach to GHG accounting, including consumption-based aspects, may help identifying a wider set of climate actions to be implemented by local authorities to reduce environmental burdens. [ABSTRACT FROM AUTHOR]

As for the academics and policymakers, more attention has been given to the issue on how to drive green development of the manufacturing through regulations and innovations. We construct the extended Crépon-Duguet-Mairesse (CDM) model and employ the panel data of Chinese manufacturing industries during 2003–2014 to examine the effects of environmental regulation on industrial innovation and green development. The findings reveal that (1) in the long term, environmental regulation has crowded out R&D investment. (2) Environmental regulation has inhibited patent outputs so that the “weak” version of Porter hypothesis is not underpinned. (3) In the short term, environmental regulation has promoted the improvements of labor productivity, energy efficiency and environmental efficiency in the manufacturing industry excluding green total factor productivity (GTFP), whereas in the long term, environmental regulation only has increased energy efficiency while it has obstructed labor productivity, which provides no support for the “strong” version of Porter hypothesis. (4) Different innovation outputs have distinct influences on labor productivity, energy efficiency, environmental efficiency and GTFP. Finally, this paper provides pertinent policy implications. [ABSTRACT FROM AUTHOR]

This paper deals with a passive cooling technique for photovoltaic (PV) panels in order to increase energy conversion efficiency through a reduced PV panel operating temperature. The proposed passive cooling technique consists of aluminum fins mounted with epoxy conductive glue on the backside surface of the PV panel (Si-poly, 50 W panel examined). Two specific rib configurations, i.e. geometries were considered in order to enhance the cooling rate from the backside surface of PV panel. The first configuration was obtained from parallel positioned aluminum fins (L-profile), while the second configuration was obtained from randomly positioned perforated L profiles. The first approach was found to be less efficient than the second one, so it was not further analysed. Main issue with the first configuration was related to its low efficiency improvement during periods of lower solar irradiation levels. The second approach, i.e. the modified geometry showed better performance response throughout the insolation spectrum, averaging about 2% in efficiency improvement relative to the total power output for the specific obtained measurement period. Further, with the specific rib geometry proposed, a more intense cooling rate was achieved. Measurements were obtained in November for a geographical location of City of Split, coast side of Croatia. The presented results in this study are useful as they provide deeper insight into the heat transfer phenomena, i.e. the general influence of a passive cooling technique with wind gusts and the limitations it brings. The examined cooling technique showed potential; however, it should be tested on a PV system with a longer measurement period in order to be able to get more precise results, which include longer periods of typical season weather and which could be also useful to determine potential effect of the cooling technique on the PV panel operating lifetime. The main benefit of the proposed passive cooling technique is reflected through more efficient PV systems, and potential increase of the lifetime of PV panels, by lowering their operating temperature. [ABSTRACT FROM AUTHOR]

Warm Mix Asphalt (WMA) has recently become an attractive alternative in pavement engineering due to its potential for significant reduction in energy consumption and carbon footprint of asphalt industry; however, concerns have been raised regarding durability of material and potential to moisture damage due to lower mixing and compaction temperatures. Furthermore, steel slag which is mostly disposed in landfills as waste material could be an appealing option as substitute of natural aggregates for asphalt concrete (AC) production because of its adequate affinity with asphalt binder. The aim of this study is therefore, to assess whether the integration of basic oxygen furnace (BOF) steel slag into Sasobit WMA technology would indicate satisfactory performance in terms of moisture susceptibility. This paper also examines if BOF slag WMA mixture can provide acceptable mechanical performance to be used as a more sustainable approach for pavement construction. To capture short-term moisture damage resistance of BOF slag WMA, specimens prepared with two Sasobit dosages were subjected to two different testing methods. Modified Lottman test and boiling water test using an image analysis technique were performed to compare moisture susceptibility and stripping resistance of BOF slag WMA and HMA (hot mix asphalt) samples with conventional mixtures. Dynamic creep test, Hamburg wheel-track device and resilient modulus test were then conducted on specimens to evaluate mechanical behavior of BOF slag WMA in comparison with BOF slag HMA and another type of WMA mixture prepared with natural aggregates. Findings showed that BOF slag WMA provided significant resistance to short-term moisture damage and therefore, could be considered as durable bituminous mixture when compared to conventional asphalt mixtures. Furthermore, BOF steel slag HMA/WMA exhibited superior mechanical behaviors compared to limestone HMA/WMA mixtures, implying that steel slag could be an effective alternative as pavement material. [ABSTRACT FROM AUTHOR]

Many Italian street lighting systems are obsolescent, considering the best available technology. Energy-efficiency improvements of street lighting systems are possible using Light Emitting Diode (LED) technology, and many cities are investigating how to effectively implement LEDs in their systems. However, the initial costs of LED luminaires are considerably higher than the costs of other technologies, and investment costs may be a barrier to implementation. In this paper, it is discussed the adoption of LED luminaires to replace the conventional lamps in public-lighting systems of Rome (Italy); calculating possible savings of energy and costs. Based on this analysis, despite the cost of LED luminaires, the use of LED technology is economically advisable. Strategic options and flexibility are introduced in the project. Specifically, it is considered the possibility of splitting LED investment into five stages, deciding whether each part should be implemented. Real options are used to evaluate the economic cost-saving of such a project, considering uncertainty of the electricity price and multi-stage investment. The economic value obtained from real option analysis is higher of that obtained from net present value because the latter does not consider some flexibilities of the project. Taking into account the sources of uncertainty, real options provide results that are more realistic. [ABSTRACT FROM AUTHOR]

This paper aims to estimate the costs and CO 2 emissions of wood biomass co-firing in the Tohoku region of Japan. A woody biomass supply system is designed, which comprises of four processes: collection, resource transportation, preprocessing, and fuel transportation. Preprocessing is further divided into two processes: drying and fuel production. Sawmill residue, construction waste, forest residue, thinning residue, and fruit-tree pruning residue are treated as raw materials. Wood chips, pellets, and torrefied pellets (known as black pellets) are regarded as bio-fuels. The raw-material and bio-fuel transportation pathways are optimized using a geographical information system (GIS). In the Tohoku area, the availability of raw-material is 3.6 PJ/y, and the results indicate that the preprocessing plant locations should be widely distributed in that region, because the resource transportation costs have a significantly greater influence on the costs and emissions than the scale effect of the preprocessing facilities. The chip production case exhibits the smallest energy consumption of 3.8 GJ/t, the lowest supply cost of 1558 JPY/GJ, and the largest CO 2 reduction of 252 × 10 3 t CO 2 /y, whereas the pellet production case exhibits a supply cost and CO 2 reduction of 1643 JPY/GJ and 229 × 10 3 t CO 2 /y, respectively. The energy consumption, energy waste, and cost of torrefaction are greater than the reductions in the transportation energy and cost due to wider distribution of the preprocessing plants; thus, the black pellet case has a larger supply cost than the chip and pellet cases. [ABSTRACT FROM AUTHOR]

The interaction of vehicles and tires with various surface and structural features of roadways impact rolling resistance, hence fuel consumption of vehicles. Efficient interaction of vehicles with the roadway provides new opportunities to reduce transportation systems environmental impacts. A roughness–speed impact (RSI) model was developed to quantify the energy and environmental impacts due to vehicle–pavement interaction. The RSI model accounts for the additional rolling resistance of vehicles resulting from pavement surface properties measured in terms of smoothness as well as vehicle efficiency improvements over time. The model uses vehicle-specific power as a basis to develop the analytical equations for representing vehicle–pavement interaction. The proposed analytical model offers advantages for easy integration to LCA software to evaluate GHG reduction policies. According to the model, one unit change of IRI (63.36 in/mile) results in an average increase in fuel consumption of 3% and 2%, respectively, at high and low speeds (65 and 35 mph) for passenger cars. Heavier trucks are less sensitive to IRI change; and one unit change in IRI on average results in 2% and 1% increase, respectively, in fuel consumption of heavy truck at high and low speeds. This paper presents case studies to explore effectiveness of a short-term policy goal concerning with the management of roadway surface features. According to the LCA results with different scenarios of pavement management policies, while vehicle efficiency accounts for about 27% of the potential total energy savings, potential savings from pavement roughness can be up to 7%. [ABSTRACT FROM AUTHOR]

China's energy conservation has received extensive attention. As the most important sector of the economy, the manufacturing industry plays a vital role in China's energy issues. Conserving energy in China's manufacturing industry (CMI) is of great significance for both China and the world. In this paper, the co-integration method is applied to test the long-term equilibrium relationship among energy consumption and three explanatory variables during the period 1980–2013. Furthermore, we use scenarios analysis method to forecast the energy demand of CMI. The results show that if the government does not properly manage the economy, the energy demand of CMI will reach 2558.97 Mtce in 2020 and 2594.18 Mtce in 2030. On the contrary, if the government attaches importance to energy conservation and takes necessary actions, energy demand in the industry will reduce to 1113.79 Mtce by 2030, which implies a large energy conservation potential for CMI. [ABSTRACT FROM AUTHOR]

Understanding the driving factors behind energy consumption changes provides insights about consumption patterns and can inform targeted energy saving polices. This paper applies a joint decomposition approach, introducing an index decomposition analysis (IDA) method into a production theoretical decomposition analysis (PDA). This integrated approach decomposed energy consumption changes into eight drivers. A subsequent empirical study of China resulted in three key findings. First, regardless of the geographic area considered, potential economic development was the largest factor driving energy consumption growth. Second, the technological change effects associated with economic development and energy savings both played significant roles in reducing energy consumption. Third, the efficiency change effects of energy use and economic development were generally unable to relieve the pressure of increases in energy consumption, especially in the eastern regions. [ABSTRACT FROM AUTHOR]

“Cleaner Production“(CP) is about less and more efficient energy and materials use and the substitution of more harmful products (for the environment and health) by less dangerous ones. CP was the reply of the industry to the call for sustainable development as launched by the WCED (1987) and further elaborated in Rio's Agenda 21 (UN, 1992). During the past 25 years, the concept was put in practice. During this period it changed in scope, methods, and application area. This provided a deeper socio-economic impact to an idea that was originally launched to awaken industry on its environmental responsibilities. This paper provides a review of essentials that contributed to the fundamental changes in CP during the most recent quarter of a century. It takes off with a review of CP definitions illustrating the changes of the content. Changes in scope are exemplified with the increasing importance of “Corporate Social Responsibility” (CSR). This includes that post-modern companies have not only responsibilities on their economic performance and the environment, but should also act on issues including human rights and resources, business ethics, and community involvement. The links between CP and green and circular economy are indicated. The CP approach is increasingly applied outside the industry. CP for sustainable tourism is discussed in more detail but is only an example of the wider application in e.g. agriculture or health services. This widening of contents necessitates more and better-adapted methods supporting the measurement of the CP components. Indicators, assessment strategies, and green accounting are increasingly improved and used more specifically and frequently. This evolution is discussed in a context of a dilution of the original environmental targets in a wider, more societal scope and the transition towards a more responsible, proactive and reliable management of the sectors applying CP. [ABSTRACT FROM AUTHOR]

Energy efficiency-oriented design is highly valued in reducing the energy consumption during product use and models for characterizing energy consumption are widely regarded as essential prerequisites of energy efficiency-oriented design. Unfortunately, correlating energy consumption with the products’ design features during the design process is a difficult task. To address this challenge, this paper uses the Function-Behaviour-Structure (FBS) ontology as a bridge to link design features and energy consumption throughout the design process and proposes a FBS-based energy modelling method. This method divides the energy modelling process into two steps. The first is to identify the required energy information and characteristics from available data on the design. The second step is to arrange the obtained information in a logical order to create energy models. Two tools, namely the modified FBS framework and the energy flow diagram, are introduced to aid designers in respectively dealing with the two energy modelling steps. To demonstrate this method, a case study considering mechanical linkage servo press is carried out. [ABSTRACT FROM AUTHOR]

The paper presents the results of the experimental research into maximum concentrations of anthropogenic emissions from typical brown low-rank coal combustion in the traditional pulverized state as well as from the combustion of coal-water slurries with or without petrochemicals. The temperature of fuel heating in the model combustion chamber varied in the range from 500 °C to 1000 °C. The relative values of concentrations of anthropogenic emissions are calculated with due consideration of key energy characteristics of the fuel: combustion heat, specific mass of the fuel component in a mixture, specific energy obtained per fuel cost. The findings illustrate considerable differences not only between the concentrations of the analyzed anthropogenic emissions, but also between the times, during which these concentrations remained high. In addition, we compare the boundary conditions (i.e. borderline or minimum sustainable ignition temperatures) necessary and sufficient for the combustion of the fuel compositions under study and analyze fuel heating and ignition delay times. Special aspects are determined of the environmentally friendly combustion of coals as part of coal-water slurries with or without petrochemicals at different temperatures: from minimum temperatures usually observed at the beginning of sustainable ignition to those typical of small- or medium-sized power plants. Concentrations of the most hazardous oxides of sulfur and nitrogen produced during coal combustion are 3–5 times higher than during coal-water slurry combustion. The differences between these parameters for coals and coal-water slurries containing petrochemicals are less noticeable. Nevertheless, the emissions of nitrogen and sulfur oxides from the combustion of coal-water slurries containing petrochemicals are at least 30–60% lower than from the combustion of coals. Taking into account the cost of the components of coal-water slurries containing petrochemicals, as well as the combustion heat and the concentrations of anthropogenic emissions, specific indicators show that coal-water slurries containing petrochemicals are more efficient than coals or the coal-water slurries without petrochemicals. If filter cakes are used as the main component of coal-water slurries containing petrochemicals, the specific indicators of such fuels grow 5–6 times higher (or even 10 times higher in special cases) versus pure coals. The research findings show that the temperature monitoring in the combustion chamber is obligatory to provide high ecological indicators. At temperatures below 1000 °C, it is possible to provide stable combustion of fuels and significantly reduce emissions as compared to the traditional high-temperature regimes (above 1000 °C). Thus, temperatures lower than 1000 °C are more rational. Finally, the conditions for the optimal coal fuel combustion are presented in terms of the environmental friendliness, energy and cost efficiency, as well as fire and explosion safety. [ABSTRACT FROM AUTHOR]

An urgent challenge in the manufacturing industry is increasing efficiency while decreasing energy consumption and environmental impact. Past studies addressing these issues have mainly focused on tool path optimization only considering machining efficiency. In this paper, we present a methodology to optimize the tool path for high efficiency, low energy consumption and carbon footprint in milling process. Firstly, the description and influencing factors of tool path are introduced. Then, a multi objective tool path optimization model with maximum machining efficiency, minimum energy consumption and carbon emission is proposed. Furthermore, the solution of the proposed model is introduced, which including two steps, one is the calculation of the number of cutter contact points (CCP), the other is using adaptive dynamic GA to optimize the connection sequence and ways of each CCP. Finally, the effectiveness and practicability of the method are verified by the machining experiments. [ABSTRACT FROM AUTHOR]

In recent years many research works have been developed to determine the amount of waste generated in building construction sites, but are mainly focused on new residential constructions. However, few studies were found quantifying construction and demolition waste (CDW) in building renovation/retrofitting projects. Current CDW ratios (amount of CDW per refurbished m 2 ) for building refurbishment projects cover a wide range of values due to the great variety of techniques that can be used in building rehabilitation projects and that will definitely influence the amount of CDW generated. Therefore, further waste quantification studies, analyzing different types of building rehabilitation projects, are needed as with the current data is not possible to make exact predictions of CDW generation. In this sense, this paper presents the results of a research project analyzing, specifically, the waste generated in building refurbishment and/or retrofitting works to improve the energy efficiency of a building. For this, the seven most common works conducted in the vertical envelope to improve energy efficiency of the building were identified and CDW generation was quantified. CDW generation ratios were stablished for each work using theoretical methods. Further, two pilot construction sites --implementing an External Thermal Insulation Composite System (ETICS) solution-- were selected and CDW generation ratios were obtained using experimental data. Results show that the highest amount of CDW generation arises when preparing the vertical surface to be refurbished. Specifically, CDW generated during an ETICS work lies between 2.46 and 65.24 kg/m 2 and 0.012–0.008 m 3 /m 2 , depending on whether the insulation layer is applied without removing the existing external coating or after its removal. Moreover, it was found that concrete, ceramic, metal and timber waste are the main waste flows generated and thus they should be further controlled onsite in order to achieve their minimization, recycling and recovery. [ABSTRACT FROM AUTHOR]

Natural gas is regarded as a cleaner alternative to coal combustion-based power generation (CPG) for urban use. Because of the insufficient natural gas reserve in China, coal-based synthetic natural gas (SNG) has been under rapid development. However, coal-based SNG production process has problems of environmental pollution and emission transfer. This paper uses life cycle assessment to compare the CPG and SNG energy production and usage routes, in order to find a reasonable way to reduce the environmental pollution and production cost. Results show that the CPG route is superior to the SNG route in terms of the haze pollution emissions, greenhouse gases emissions, coal resource consumption and life cycle cost. However, the water consumption of the CPG route is much higher than that of the SNG route. The SNG route is more suitable to adopt in water-deficient areas. [ABSTRACT FROM AUTHOR]

The ’circular economy’ paradigm is taking hold in the mobile phone sector as a solution to increasing resource use. This paper explores three dimensions of the consumption of mobile phones: timing of replacement, repair, and reuse. Combining quantitative evidence from a large-scale questionnaire survey (n = 988) with 25 qualitative household interviews, we identify the consumers’ motivations underpinning their considerations regarding replacement timing, replace versus repair, and new versus second-hand phones. The findings from this study suggest that mobile phone replacements are not only based on a desire for the new, but primarily on the perceived obsoleteness of the current phone. We identify three forms of perceived obsolescence, being either related to a phone’s 1) basic functionality, 2) up-to-dateness, or 3) ability to keep up with social practices. Furthermore, it is shown that the perceived speed of obsolescence is key to considerations of phone repair and reuse. Overall, the results call into question the prevalent picture of novelty-oriented mobile phone consumers, exposing the paradoxical nature of consumer strategies to resist the fast pace of obsolescence. [ABSTRACT FROM AUTHOR]

Improvement of coal consumption efficiency is very important both for China in solving its problems of energy security and environmental pollution and for the world in addressing the issue of greenhouse gas emissions. Using a total-factor framework, this paper employs a data envelopment analysis (DEA) approach to evaluate the coal consumption efficiency of six energy intensive sub-industries in China in 2015. Coal consumption efficiency is factorized into economic efficiency and environmental efficiency, with sulfur dioxide, nitrogen oxide, and industrial smoke, dust and soot emissions treated as undesirable outputs of energy consumptions. The results show the following. (1) Of the six energy intensive sub-industries studied, two exhibit both DEA-effective coal economic efficiency and coal environmental efficiency. Coal economic efficiency is found to be greater than coal environmental efficiency, indicating that the benefits of economic efficiency have masked the negative effects of the environmental impact. China should therefore pay more attention to the clean utilization of coal. (2) Low environmental efficiency mainly resulted from the joint effects of pure technical efficiency and scale efficiency; therefore, enterprises in these industries must engage in management efforts to improve their ability to manage large enterprises. (3) The energy intensive industries characterized by coal environmental efficiency that failed to achieve pure technological effectiveness all exhibited input redundancy or output inadequacy of varying degrees while showing a potential for energy conservation and emissions reductions. [ABSTRACT FROM AUTHOR]

The special volume on green and sustainable chemistry and engineering has fourteen papers that were considered relevant to the present day issues and discussion, such as adequate use of raw materials and efficient energy, besides considering renewable sources for materials and energy; and changing economical canons towards circular economy. Businesses, governments and Society are facing a number of challenges to tread the sustainability path and provide wellbeing for future generations. This special volume relevance provides discussions and contributions to foster that desirable future. Chemicals are ubiquitous in everyday activities. Their widespread presence provides benefits to societies’ wellbeing, but can have some deleterious effects. To counteract such effect, green engineering and sustainable assessment in industrial processes have been gathering momentum in the last thirty years. Green chemistry, green engineering, eco-efficiency, and sustainability are becoming a necessity for assessing and managing products and processes in the chemical industry. This special volume presents fourteen articles related to sustainable resource and energy use (five articles), circular economy (one article), cleaner production and sustainable process assessment (five article), and innovation in chemical products (three articles). Green and sustainable chemistry, as well as sustainable chemical engineering and renewable energy sources are required to foster and consolidate a transition towards more sustainable societies. This special volume present current trends in chemistry and chemical engineering, such as sustainable resource and energy use, circular economy, cleaner production and sustainable process assessment, and innovation in chemical products. This special volume provides insights in this direction and complementing other efforts towards such transition. [ABSTRACT FROM AUTHOR]

Severe environmental problems are resulted from the rapid growth of electricity consumption in China, since thermal power plant occupies the predominant position in power generation and releases large amount of pollutants and greenhouse gas. Electricity consumption of residential sector grows even faster than that of industrial sector in recent years. Residential sector is increasingly believed to have huge potential of energy saving and efficiency improvement. This paper aims at discovering the regional difference of household electricity consumption (HEC). First, a research framework is provided to identify the characteristics of HEC from the following three dimensions, consumption volatility, pattern similarity and temperature sensitivity. Households are divided into different groups in each city. The major household groups that account for the largest proportion are identified and then regarded as representatives of different cities. The fluctuation characteristics of their typical load profiles are compared and discussed in detail. Moreover, we design an Empty City Index (ECI) to further discuss the relationship between HEC and the population flow in special time intervals, for example, Chinese Spring Festival. The empirical study demonstrates that population outflow during Spring Festival is more obvious in wealthier city. Through k-means clustering, typical household groups as well as their typical load profiles are identified in each city. And the results show that under the current tiered pricing for household electricity (TPHE), nearly 10% households in each city still have potential for load reduction and load shifting. For the entire Jiangsu province, such households account for 12.5%. Policy implications and the applicability of this study are suggested and discussed respectively to government, household customers and electric power companies. [ABSTRACT FROM AUTHOR]

The heat source types in China were not limited to the coal, other types of energy were introduced into the heating energy consumption in recent years, and therefore the specific regional impact of the heating emissions could not be obtained accurately according to the current achievement. Based on this, this study aimed to quantify the impact of the heating emissions on the air quality in an efficient and accurate way. A new method was proposed for investigating the quantitative impact of the heating emissions on the air quality index in this paper and its assumptions and accuracy were verified as well. The data employed in this method is extracted from Ministry of Environmental Protection Data Centre, Qingyue open source and Shanghai Central Meteorological Observatory. The key prerequisites of the proposed method were discussed in this study. By calculating, the averaged absolute difference of the meteorological parameters, namely Clo, WD, WS and P, is 3.58%, 2.40%, 3.21% and 3.94%, respectively. The difference ratio of the industrial emissions relative to the total emissions is as low as 4.3%. The optimal principal component number is six for the proposed method, which can satisfy the accuracy requirement with minimum workload. Compared with the results in previous similar studies, the proposed method showed excellent performance in analyzing the regional impact of the heating emissions on ambient air quality in China. Moreover, a total of 64 North cities in China were analyzed based on the proposed method to promote the knowledge on the influence of heating emissions on the environmental quality and the related parameters were provided in this study. [ABSTRACT FROM AUTHOR]

Carbon emission and energy consumption are two important factors need to be addressed while production planning for sustainable development. As the population is increasing and demand of various commodity is increasing rapidly therefore production planning is required which reduces the environmental effect, improves energy efficiency and also meet the forecasted demand. In this paper, two objectives carbon emission and energy consumption are taken in parallel consideration and methodology is proposed for production planning via existing and new process routes for minimizing one objective while imposing a maximum limit on the other objective. The proposed methodology is graphical and based on the concepts of pinch analysis that gives physical insight to the problem. Current production scenario utilizes existing process routes and to meet the future demand new process routes (based on best available techniques) are to be added. Production planning is to be calculated via each process route in order to minimize energy consumption and carbon emission. Proposed methodology is illustrated via two examples. First example consists of general production planning and the second example consists of production planning of crude steel. The planning is carried for two cases, in the first case carbon emission is constrained within a maximum limit and energy consumption is minimized while in the other case energy consumption is constrained within a maximum limit and carbon emission is minimized. Thus, proposed methodology provides flexibility to the planner to consider either of the two cases based on scenario and other requirements and it reduces the excess burden of carbon emission and energy consumption while satisfying the demand. [ABSTRACT FROM AUTHOR]

Carbon emission is not as free as they used to be. Under the carbon emission tax policy, manufacturers face a choice of whether to reduce their carbon emission through remanufacturing or low-carbon technologies. In this paper, we characterize the optimal carbon emission tax policy through a two-period production decision model, in which new products and remanufactured products are clearly distinguishable. The effects of a carbon emission tax on the optimal production decision of manufacturing and remanufacturing is investigated. It is found that there are rational remanufacturing production strategies for different products based on different remanufacturing cost savings and carbon emission savings per remanufactured product under a carbon emission tax policy. Manufacturers can offset the cannibalisation and negative economic impact of the carbon emission tax policy by making low-carbon emission technology investment. Furthermore, the government can stimulate the manufacturer to invest in carbon emission reduction technologies and remanufacturing simultaneously by choosing a reasonable carbon emission tax. [ABSTRACT FROM AUTHOR]

Over the recent decades, there has been an increasing focus on energy-efficient operation of vessels. It has become part of the political agenda, where regulation is the main driver, but the maritime industry itself has also been driven towards more energy-efficient operation of the vessels, due to increasing fuel costs. Improving the energy efficiency on board vessels is not only a technical issue - factors such as awareness of the problem, knowledge skills and motivation are also important parameters that must be considered. The paper shows how training in energy-efficient operation and awareness can affect the energy consumption of vessels. The study is based on navigational, full-mission simulator tests conducted at the International Maritime Academy SIMAC. A full-mission simulator is an image of the world allowing the students to obtain skills through learning-by-doing in a safe environment. Human factors and technical issues were included and the test sessions consisted of a combination of practical simulator exercises and reflection workshops. The result of the simulator tests showed that a combination of installing technical equipment and raising awareness - making room for reflections-on and in-action - has a positive effect on energy consumption. The participants, on average, saved approximately 10% in fuel. [ABSTRACT FROM AUTHOR]

Recently, performance evaluation of coal-fired power generation with high pollution based on data envelopment analysis (DEA) method has become an advanced research hotspot in China. Instead of a single process in previous studies, we divide the production system of coal-fired power plants into the production process and pollutants abatement process, with pollutant intermediates as the link to connect the two processes in the current paper. Then we present a new two-stage network DEA model to evaluate the performance of China's coal-fired power generation by improving the link constraint that different with traditional network DEA approaches. Meanwhile, we conduct an empirical study to verify the applicability of the proposed approach and find that the proposed model is more effective than the previous models in evaluating the inefficiencies of coal-fired power generation. The empirical results also show that: the inefficiencies of the pollutants abatement process bring poor performance of the regional coal-fired power plants; and the efficiency results vary greatly among different areas of China, efficiency is best in the west area but the worst in the northeast area. Finally, some appropriate propositions are present in order to create better conditions for China's sustainable development. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach for systematic energy efficiency evaluation and optimization in turning operations, combining spindle, chiller and material removal models. Framing a joint machine-process design approach, the proposed study aims at selecting optimal combinations of cutting parameters (feed rate, depth of cut and spindle speed) for a given spindle-chiller assembly, able to minimize the energy consumption. Contrary to most of the literature, where the efficiency analysis is fully empirical, relying on extended cutting test campaigns, here a model-based approach is adopted. The goal is to characterize a key subsystem of modern machine tools, often used in both turning and milling machines, composed by a permanent magnet brushless direct-drive spindle with a dedicated chiller unit. Analytical relationships are identified, producing efficiency maps as a function of various process parameters. Physic-based models are exploited, reproducing electrical and mechanical energy dissipation occurring in the spindle and chiller units and in the material removal process. The models parameters are identified by a reduced set of spindle ramp-up and cutting tests, executed in an industrial context. Then, an overall process efficiency optimization is performed and discussed. [ABSTRACT FROM AUTHOR]

To stimulate private sector investments and promote energy efficiency, in recent years through Public Private Partnership arrangements, the public sector uses private companies, the Energy Service Company (ESCO), to perform one or more activities related to the provision of energy services, and the contractual arrangements defining the contracting parties' obligations and rights are traditionally based on Energy Performance Contracting (EPC). Although EPC is a valuable model for delivering public energy efficiency projects, the adoption is still far from its vast potential mainly because of two unresolved issues: the dilemma of equally sharing the benefits between the public and private parties so as assuring a win-win condition, and the lack of adequate public procedures that support the selection of the most appropriate EPC schema given certain circumstances and projects' characteristics. The existing literature have analyzed the advantages of EPC mechanism for delivering energy efficiency projects and explored the critical success factors of EPC. However, it does not provide any solution to address the issues that hamper the adoption of EPCs in public sector. To fill this gap, this paper proposes a model for assessing and benchmarking the net benefits of the different EPC structures, so as choosing the EPC schema that creates a ‘win–win’ solution for both the ESCO and the government, by balancing the private sector's profitability needs and the public sector's economic interests. The assessment of the benefits of the EPC schema for contractual parties and the benchmark among the contracts are based on an economic approach, which expresses the net benefit gained by each party through the three EPC contracts in monetary terms and benchmarks the three EPC schema through the Net Present Value (NPV) method. The win-win condition is ensured by the contract that minimizes the difference between the net profits (NPV) gained by the contractual parties. This will support the public authority in the decision-making process about the EPC structure to be adopted to develop an energy efficiency project as a PPP. To demonstrate the applicability of the proposed model, we apply it to an energy efficiency project launched by the Municipality of Noci (Southern Italy). [ABSTRACT FROM AUTHOR]

This paper contributes to green product development by identifying the green products with the highest potential for growth in a country. To address our aim, we use the concept of product proximity and product space and, borrowing from the results of recent studies on complexity economics, we advance that the green products with the highest potential for growth among all green products in a given country are those being in close proximity to the products a country produces with high Relative Comparative Advantage (RCA). We test this hypothesis performing a regression analysis. We build the product space for 141 different countries for the years between 2005 and 2013 and for each country we compute the maximum proximity of each green product to the products with high RCA (i.e., the proximity of the product source of competitive advantage closest to the green product considered). Results confirm that green products with high maximum proximity to the products with high RCA had the highest growth. So doing, we contribute to the literature by providing a new application of the product space as a policy making tool for green development. We also provide several applications of the proposed method. [ABSTRACT FROM AUTHOR]

The aspiration of a circular economy is to shift material flows toward a zero waste and pollution production system. The process of shifting to a circular economy has been initiated by the European Commission in their action plan for the circular economy. The EU Ecodesign Directive is a key policy in this transition. However, to date the focus of access to market requirements on products has primarily been upon energy efficiency. The absence of adequate metrics and standards has been a key barrier to the inclusion of resource efficiency requirements. This paper proposes a framework to boost sustainable engineering and resource use by systematically identifying standardization needs and features. Standards can then support the setting of appropriate material efficiency requirements in EU product policy. Three high-level policy goals concerning material efficiency of products were identified: embodied impact reduction, lifetime extension and residual waste reduction. Through a lifecycle perspective, a matrix of interactions among material efficiency topics (recycled content, re-used content, relevant material content, durability, upgradability, reparability, re-manufacturability, reusability, recyclability, recoverability, relevant material separability) and policy goals was created. The framework was tested on case studies for electronic displays and washing machines. For potential material efficiency requirements, specific standardization needs were identified, such as adequate metrics for performance measurements, reliable and repeatable tests, and calculation procedures. The proposed novel framework aims to provide a method by which to identify key material efficiency considerations within the policy context, and to map out the generic and product-specific standardisation needs to support ecodesign. Via such an approach, many different stakeholders (industry, academics, policy makers, non-governmental organizations etc.) can be involved in material efficiency standards and regulations. Requirements and standards concerning material efficiency would compel product manufacturers, but also help designers and interested parties in addressing the sustainable resource use issue. [ABSTRACT FROM AUTHOR]

With the penetration of smart grid into factories, energy-efficient production scheduling has emerged as a promising method for industrial demand response. It shifts flexible production loads to lower-priced periods to reduce energy cost for the same production task. However, the existing methods only focus on integrating energy awareness to conventional production scheduling models. They ignore the labor cost which is shift-based and follows an opposite trend of energy cost. For instance, the energy cost is lower during nights while the labor cost is higher. Therefore, this paper proposes a method for energy-efficient and labor-aware production scheduling at the unit process level. This integrated scheduling model is mathematically formulated. Besides the state-based energy model and genetic algorithm-based optimization, a continuous-time shift accumulation heuristic is proposed to synchronize power states and labor shifts. In a case study of a Belgian plastic bottle manufacturer, a set of empirical sensitivity analyses were performed to investigate the impact of energy and labor awareness, as well as the production-related factors that influence the economic performance of a schedule. Furthermore, the demonstration was performed in 9 large-scale test instances, which encompass the cases where energy cost is minor, moderate, and major compared to the joint energy and labor cost. The results have proven that the ignorance of labor in existing energy-efficient production scheduling studies increases the joint energy and labor cost, although the energy cost can be minimized. To achieve effective production cost reduction, energy and labor awareness are recommended to be jointly considered in production scheduling. [ABSTRACT FROM AUTHOR]

The article reassesses a recent case study on six bioethanol production processes in China, to develop a methodology that discriminates the most energy-efficient process. The original research explored the joint method of Life Cycle Assessment and Data Envelopment Analysis (LCA + DEA). However, DEA is sensitive to problems with a disproportionate number of variables to alternatives and LCA usually requires analysis with several inputs and outputs. The original research indicated two sources as being tied for energy efficiency, which is not relevant to decision-makers aiming to invest in the most efficient process. The method proposed here uses a combinatorial and probabilistic approach to improve discrimination and create scenarios for the reduction of inputs and the increase of outputs, even for efficient processes. Results show that the proposed method has better discriminatory power than the referenced paper. [ABSTRACT FROM AUTHOR]

Dry and wet routes in the ceramic tile manufacturing process refer to two different technologies for preparing the raw materials for the forming stage. Both result in a granulated solid ready for use in the pressing stage, but with different characteristics. The dry route was the first to be developed. As quality standards and tile sizes increased, the wet route was developed and introduced successfully into the manufacturing process. Since 1990, the wet route has been the most used around the world to prepare ceramic tile body raw materials. The powder produced by the wet route has finer particles and higher flowability, which has allowed the production of higher quality ceramic tiles of larger sizes. However, the process uses more energy and water and, consequently, is more costly in both economic and environmental terms. New developments in dry milling and granulation systems combined with the growing awareness of environmental impacts and European Union energy policy, and successful uses of the dry route in some important tile producer countries (especially Brazil), are leading to a reconsideration of the tile production processes. In the current context, implementation of the dry route is being considered an interesting alternative for the production of ceramic tiles with lower environmental costs. This has resulted in a significant number of studies of the technology from applied research centres and machinery producers. The present paper provides an up to date technical and environmental comparison of the dry and wet routes, based on the most recent advances, to add to the debate on the use of the dry route to produce high quality ceramic tiles. [ABSTRACT FROM AUTHOR]

Freeze drying is a drying technology that removes water from a target by sublimation of ice to vapor. Drying at low temperature and pressure (below the triple point) results in fewer physical and chemical changes to the dried products compared with the changes observed when using other drying technologies, leading to producing a high quality product. However, the weak point of freeze-drying technology is its large energy consumption. It is therefore necessary to reduce the energy required for the freeze-drying process and the energy costs of production so that this technology can be extended to the drying of other products. In this paper, a new energy-saving freeze-drying process based on the concept of self-heat recuperation technology was proposed. The energy required for the proposed process was compared with a conventional technique using a commercial process simulator. From the simulation results, more than 80% of the energy required for drying can be saved by using the proposed process. [ABSTRACT FROM AUTHOR]

This paper aims to extract determinants of efficiency in an industrial-scale biogas project treating food waste in a major Asian megacity. The research involved a 4-step methodology combining statistical and operations research tools. The findings were as follows: (1) the project suffered from high variability and low performance across several important process parameters; (2) Principal component analysis (PCA) showed that approximately 40.51% of variability in the data could be explained by two principal components; (3) Data envelopment analysis (DEA) revealed that 47% of the decision making units (DMUs) were inefficient, and 73% of DMUs exhibited increasing returns to scale; (4) regression results showed that adjusted R 2 values ranged between 0.913 and 0.996 for the models of DEA efficiency, and significant explanatory variables were extracted based on type III sum of squares. This research is significant in the biowaste-to-energy literature in that it provides a robust method for identifying process bottlenecks in industrial-scale anaerobic digestion of food waste. [ABSTRACT FROM AUTHOR]

Supporting environmentally-conscious design of moulds is the ultimate objective of the here presented advisory tool. Relying on a careful estimation of the energy used for the injection moulding process, the designer is guided towards the development of green(er) solutions. As shown by literature and through a preliminary LCA screening analysis, most of the environmental impacts of a mould are directly connected to the energy consumed during the injection phase. This paper proposes a guideline for a reliable and sensitive energy estimation of the injection moulding process, taking into account not only the part and the material to be moulded, but also the specifications of the mould, the injection moulding machine and the injection moulding process parameters. The accurate estimation of the energy consumed may radically improve the estimation of the overall environmental impacts of the mould and of the moulded product, and provide a value-added support for eco-driven decision making since the mould design phase. This work aims at contributing to the development of new methodologies to help injection moulding industry to develop more sustainable parts, moulds and processes. [ABSTRACT FROM AUTHOR]

Product life cycle (PLC) is a series of life cycle phases which a product will go through in its lifetime. There are several issues with the life cycle of a product when looked from the environmental impact perspective. These issues impact resource scarcity, cause adverse effects on the environment and loss of embodied energy as waste. Some of the potential solutions to these issues, as proposed in literature, are to carry out various End-of-Life (EoL) recovery processes on products including their recycling, reuse and remanufacturing. These EoL recovery processes help in reclaiming materials, components and sub-assemblies from used products and make them available for new products, or extend life of the products as a whole. In order to efficiently carry out these EoL recovery processes, a pre-requisite is disassembly. Disassembly processes are closely related to the design specifications of a product. Therefore, designers should incorporate disassembly considerations into a product during its early design stage itself in order to make disassembly of the product easier when it reaches the EoL phase. Therefore, the objective of the work reported in this paper is to support designers in evaluating some of the major factors influencing disassembly, both individually and together, so as to assess the trade-off among these in an integrated manner during early design stages of the product's life cycle, thereby helping designers compare and select alternative designs of a product that have better disassembly potential at the EoL phase. An Integrated Framework has been developed to support designers in the above evaluation process. For practical application, the Framework has been implemented into a computer based tool called IdeAssemble, and the usefulness of the tool is tested with a design experiment. The results indicate that the tool supported designers in decision making on alternative designs better than when designers evaluated without the tool. IdeAssemble tool could be used as early as during the embodiment design stage of a product when information on materials, geometry, disassembly tools and types of disassembly task are available to the designer. [ABSTRACT FROM AUTHOR]

The energy consumption of the service sector in China is larger than the total energy consumption of Japan, great importance should be attached to the energy efficiency of Chinese service sector. Considering undesirable output and regional heterogeneity, a meta-frontier slack-based efficiency measure (MSBM) approach is adopted in this paper to measure the energy efficiency of Chinese service sector using provincial panel data of China during 1995–2013. The empirical results show that, the energy efficiency of the service sector in China is 0.62 and 0.85 under meta-frontier and group-frontier technologies. The eastern regions show the best performance in energy efficiency, the central region follows and the western region shows the poorest performance. Only the eastern region shows an increasing trend in the energy efficiency of Chinese service sector. The potential of energy efficiency improvement for Hainan, Guizhou, Qinghai, Ningxia, Gansu and Shaanxi are relatively high. Some policy recommendations are proposed to improve the energy efficiency of Chinese service sector. [ABSTRACT FROM AUTHOR]

Measuring and targeting energy performances of manufacturing plants and their subsystems is the first, critical step to understand their energy behavior, to identify energy management opportunities and to evaluate energy savings. In addition, this activity has become always more important in the last decades, as Energy Management Systems and energy management practices based on continuous improvement and people engagement have been largely adopted, requiring the introduction of new energy consumption control systems capable to identify the standard operative energy behavior and performance of systems and machines and their energy baseline, to point out contingent deviations of energy performances from the baseline and to identify possible causes and clearly attribute responsibilities of such deviations. In this context, several attempts have been presented in literature trying to identify methods to create Energy Performance Indicators so as to satisfy these requirements, but most of them are focused either on a physical or on economical definition of the problem (and therefore either on a process/appliance level or on an aggregated level), neglecting the necessity to develop an integrated system to combine those two approaches to the problem and deliver appropriate information to each hierarchical level and function of the company. In addition, even when these indicators are identified, a proper system to monitor and control their evolution over time is neglected. In this paper, a novel methodology to manage Energy Performance by developing, analyzing and maintaining Energy Performance Indicators in manufacturing plants is presented, which has been created to fill this gap and taking into account ISO 50001:2011 and ISO 50006:2014 requirements, in order to be as general and widely applicable as possible. The proposed methodology allows an immediate identification of manufacturing plant's energy performance deviations through Energy Performance Indicators monitoring over time and an easy association of causes and responsibilities to such deviations, in order to allow companies to rapidly react defining action plans and resetting targets if necessary; it has also been validated through an industrial case study, which will eventually be presented. [ABSTRACT FROM AUTHOR]

Literature reviewed suggests energy maturity models are in their infancy in the energy management sector, with little practical guidance for their implementation in multi-site organisations. In addressing this gap, this paper presents the development and implementation of an Energy Management Maturity Model for multi-site industrial organisations with a global presence, considered as a fundamental step towards continuous improvement and optimal energy efficiency. The developed maturity model provides a global view of the overall network readiness for engaging in energy efficiency by adapting and enhancing existing ‘site focused’ maturity models to cater for a multi-site industrial organisation. The model enables two-way communication between global and local energy management teams; not only are the individual sites benchmarked but the global energy management team receives feedback and a gap analysis on their performance from the network of sites perspective. The evaluation framework created around the maturity model supports automated prioritization of elements with larger deviations from the site and network median score. In parallel it provides the global energy management team with direction on where the organisation needs to focus central efforts to support the individual sites. The maturity model enables the evaluation of key non-technical aspects of energy management required for continuous improvement on a multi-site and global scale. [ABSTRACT FROM AUTHOR]

This study presents a novel decentralized sanitary separation system as a zero-discharge solution for blackwater (BW) (faeces, urine and toilet paper) treatment for remote tourist facilities located in sensitive areas. The system operates with low water and energy consumption, enables safe operation and requires low maintenance. The BW was collected from two vacuum toilets (VTs) (0.8 L flush water) and separated in peat filters (PFs) to obtain a liquid fraction (LF) and a solid fraction (SF) of the BW. The LF from the PFs was thereafter treated in a biofilter (BF) and finally evaporated in the evaporation module (EM) powered by solar vacuum collectors (SVC). In the PFs, particles larger than 1 mm were reduced from the BW by 96.5%. Furthermore, the total suspended solids (TSS) mass removal efficiency of the PFs averaged 51.5%. Reduction of ammonia through nitrification was noticeably enhanced after 100 days of the system operation (max. 55.8%). 21.2% or 0.54 kg of total phosphorus (TP) was retained in the PFs, to be further composted and reused for agricultural purposes. An additional 5% or 0.10 kg of TP was retained in the BF. The final step of the LF treatment was in the EM at a sanitizing temperature of >60 °C to prevent the release of human pathogens into environment. With a total electricity consumption of 9.1 kWh/day and a heat consumption of approximately 5.1 kWh/day gained by the SVC, the system successfully integrated different approaches to treating the BW, recycling nutrients, and removing pathogens. [ABSTRACT FROM AUTHOR]

As one of the largest energy consumers, the transport sector generated direct and indirect emissions which significantly affect the environment, accounting for approximately one-third of the total carbon emissions. While the major impacts are from transport energy use and emissions, very few studies attempted to examine the impacts from transport infrastructure, especially at a city or country level. This paper, taking Shenzhen in China (a fast developing megacity) as the case study, is specially designed to quantify the carbon footprint of the urban roads by using streamlined life cycle assessment method. For given years (ranged from 2004 to 2013), various activities of urban roads (e.g. newly planned road construction, maintenance of road in use, and road renovation and demolition) have been examined in this study. The results show that the total carbon footprint from urban roads in Shenzhen was 260 (±20) thousand tons CO 2 e in 2013. The major contributor was the materials use (embodied impact) from newly constructed roads, which accounts for 52.3% of the total carbon footprint, followed by the maintenance stage (24.3%). The eco-design process of road construction plays a vital role in achieving the effective carbon footprint reduction. These findings help to better understand the carbon footprint from urban roads in megacities, and provide useful inputs for policy making process in terms of identifying carbon reduction opportunities for the transport sector. In addition, the methodologies are useful for the quantification of carbon footprint in other cities of China and beyond. [ABSTRACT FROM AUTHOR]

In order to reduce the energy consumption of machine tool, the process parameters were optimized by the optimization model with the cutting specific energy consumption (CSEC) and the processing time. Based on the energy consumption characteristics of the numerical control (NC) machine tool, the energy consumption module of NC machine tool was analyzed. The power composition of machining process which was based on energy consumption module was proposed, and then CSEC was given with the cutting process parameters. The optimization model to minimum cutting specific energy consumption and minimum processing time was established with the process parameters under the actual constraint conditions in the manufacturing process. The multi-objective optimization model was transformed into the single objective optimization model by introducing the subjective and objective comprehensive weights and solved by the quantum genetic algorithm. When the optimization goal was to trade off processing time and CSEC to reduce the energy consumption, the selecting of the milling parameters should consider the complex effect if the constraints could be met with, large feed speed and large milling depth could benefit if the constrains of milling process were met with. The processing energy consumption of optimized process parameters decreased 27.21% compared with that of preferred process parameters while CSEC was reduced 32.07% and the processing time was reduced 34.11%. The proposed approach in this paper provided an efficient solution to reduce the impact of the environment caused by energy consumption and to realize the sustainable manufacturing. [ABSTRACT FROM AUTHOR]

Issues relating to the illumination of historical minor centers have taken on increasing significance in debates on urban rehabilitation. Interventions must ensure balance with the surrounding environment whilst implementing high-efficiency, energy-environment systems, and enhance architectural structures. The research presented in this paper aims to identify appropriate strategies and effective criteria for lighting design in historical centers. The methodology developed is based on transcalar analysis and has been applied to a village in the Abruzzo Region (Italy). The methodology involved surveys carried out in the urban context together with up-to-date and detailed analyses aimed at highlighting the criticalities and potentialities of the village in the case study. This allowed the elaboration of intervention strategies applied to two different areas: one within the historical nucleus of the village and the other in a peripheral area. This research has contributed to enriching the current debate on so-called “inland areas”, including developing new ways to benefit from the special characteristics of these areas and implementing more sustainable action. [ABSTRACT FROM AUTHOR]

This paper proposes a dynamic control algorithm to enable an energy-aware single machine scheduling under the time-varying electricity pricing policy, in which price rates remain fixed day-to-day over the season. The key issue is to assign a set of jobs to available time periods where different electricity prices are assigned, while considering requested due dates of jobs so as to minimize total penalty costs for earliness and tardiness of jobs and total energy consumption costs, simultaneously. As the first contribution of this study, we develop a new mixed integer nonlinear programming (MINLP) model that aims at determining job arrival times and resulting earliness and tardiness of jobs and energy consumption costs for machine idle and normal processing. Second, an efficient heuristic approach based on continuous-time variable control models and algorithm is developed. The proposed heuristic adaptively changes job arrival times and due dates, which finally determine production sequence over the time periods of different electricity prices, machine turn-off, and machine idle with minimum energy consumption costs and just-in-time (JIT) penalty. Energy and JIT performance of the proposed approach is examined using real energy and machining parameters of a HAAS machine and compared to those of the metaheuristic approach. For relatively large size data groups, the proposed approach incurs about 4 ∼ 11 % higher energy consumption costs on average, which are offset by up to 99 % lower JIT costs, resulting in 10 ∼ 94 % lower total costs on average compared to the metaheuristic approach. The proposed time-scaled heuristic algorithm yields extremely short computational time, which enables production managers to flexibly select proper production strategies and to implement them for different production environments. [ABSTRACT FROM AUTHOR]

Reducing energy consumption is becoming a more and more essential consideration for low carbon manufacturing. In this paper, an operation scheduling approach is proposed for a multi-hydraulic press system to explore the potential on energy saving at system level. In the multi-hydraulic press system, a drive is composed of several motor-pumps and supplies energy to each press according to a given schedule. The scheduling formulation is developed based on power models of the forming process on an individual press. At single press level, models of energy conversion units, including asynchronous motors, piston pumps, hydraulic cylinders, valves and pipes are built by identifying their energy dissipation characteristics. Based on the established model of a single press and scheduling formulation, the energy consumption model and makespan at multi-press level are obtained. In order to balance makespan and energy consumption, the duration of each operation is adjusted by optimizing the configuration of the drive and the schedule of operations. To demonstrate the applicability of the proposed approach, a case study on a four presses system is presented. The results show that this approach is effective in identifying schedules to reduce makespan and total energy consumption during forming processes. [ABSTRACT FROM AUTHOR]

Sustainable agriculture, food security, and welfare of the farmers require an integrated analysis of the performance of the agricultural sector. In this paper, we follow the energy-environment-economy framework and focus on decomposition of changes in the energy-related greenhouse gas (GHG) emission in agricultural sectors of the selected European Union (EU) countries. The research relies on country-level data from FAO and Eurostat describing economic activity, energy use, and GHG emission in the agricultural sectors of the European countries during 1995–2012. The main drivers (carbon factor of energy consumed in agriculture, energy intensity of agricultural production and growth in agricultural production) and their impacts on the energy-related GHG emissions in agriculture are analysed for selected countries. The Generalized Divisia Index is applied to decompose the changes in the energy-related GHG emissions. France, Latvia, and Belgium appeared as the only countries with increase in GHG emissions during 1995–2012. In the case of France, energy intensity went up along with increase in the scale of agricultural production. In Latvia and Belgium, an increase in carbon factor appeared as the major factor driving an increase in GHG emissions. The appropriate policies need to be employed in these countries seeking to reduce GHG emissions from energy consumption in agriculture. Improvements in energy efficiency appear to be a more feasible mean for ensuring further reductions in GHG emission. [ABSTRACT FROM AUTHOR]