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This study uses a spatial Durbin error model (SDEM) approach to analyze adoption trends for residential energy-efficiency measures (EEMs) in New York state. Model results are based on socioeconomic, building, and household demographic characteristics during the 2012–2016 period. Our study's results confirm that a positive correlation exists between EEM uptake and multifamily buildings, gas-heated homes, education effects, and spatial spillover effects among neighboring ZIP codes. The results show that building attributes hold a relatively high explanatory power over EEM adoption compared with socioeconomic characteristics. Our results show that energy-efficiency policies can create positive and significant neighborly effects in promoting EEM adoption. The developed SDEM methodological framework provides useful insights in identifying energy-efficiency opportunities that exist in rural, suburban, and urban communities, highlighting the need to review policy incentives periodically to address underlying changes in the built environment and spatial disparities in energy-efficiency investments. [ABSTRACT FROM AUTHOR]

Building envelope design is rising in relevance and, within this specific context, the application of passive and climate adaptive building shells (CABS) is investigated as an opportunity for energy savings and improvement of users' thermal and visual comfort. The paper reports a research concerning the climatic based development of a customized dynamic façade based on a passive self-adaptable system to climatic conditions via actuators. The solution is designed with the aid of a customized workflow based on Ladybug Tools, which is calibrated according to recorded thermal-mechanical behaviours and allow to predict the energy and thermal/visual comfort dynamic performances. The system is tested in four European climates and sky types, tracing the scenarios of its adaptability under various settings. The results indicate that the system by its constant mechanical changes due to the variation of temperatures provides a higher degree of adaptation, energy-saving and indoor thermal and visual comfort. [ABSTRACT FROM AUTHOR]

The world has been grappling with energy efficiency for decades. Much attention has been focused on how government can encourage energy efficiency, but there has been essentially none on industry perspectives of which government interventions are necessary to encourage these actions to become the norm. We address this gap through a study of industry views as to which government interventions prompt corporate actors to adopt energy efficiency measures across three industries (building and construction, energy/utilities, and hospitality) in Canada and the United Kingdom. Our findings demonstrate that industry responses mirror recent literature on the need for a mixture of policy tools. Where our findings depart from this literature is that we find a strong endorsement of the use of information provided by government and antipathy towards the use of economic instruments to engender new norms of behaviour. This finding is particularly significant given that much of the literature focuses on the benefits of economic instruments in advancing sustainability goals. We also find the express norms found in command and control instruments are, in the views of industry actors, necessary to make a shift from energy efficiency actions being carried out only by leaders within the industry to these actions becoming standard. [ABSTRACT FROM AUTHOR]

Ti6Al4V is extensively employed in the aviation, biomedical, and energy industries due to its high strength at elevated temperatures, low thermal conductivity, and high corrosion/creep resistance. However, these intrinsic properties have brought many technical challenges during the machining process of turbine blade shape. However, the recent advancements in flexible and precision machining in the state-of-the-art turn-mill machine tools can enable the manufacturing of high-quality turbine blades. In this study, a methodology is developed for the precision and energy-efficient machining of Ti6Al4V turbine blades on turn-mill machine tools. The stock-to-part manufacturing procedure includes the initial turning operation on bar stock, rough flank milling, and final surface finish milling. The developed method encompasses five stages. Utilizing a reconfigured Particle Swarm Optimization algorithm, a 3D Pareto optimal solution set is generated to evaluate trade-offs between surface roughness, specific cutting energy, and material removal rate. Also, the effect of different inclination angles is analyzed, and the optimization method is repeated with varying lead and tilt angles. This work shows that the surface roughness can be effectively reduced by including inclination angles into optimization while improving the machining process's energy efficiency. [ABSTRACT FROM AUTHOR]

The conventional refrigeration ejector cycle utilizes a constant temperature process during motive heat consumption needed for vapor generation. This may be thought of as the main restriction concerning the application of low-grade heat as a motive source by these systems since it results in required significant mass flow rate with a small temperature drop of heating fluid. The first proposed novel approach is an ejector flash cycle (EFC) in which the working fluid is heated up to the saturation temperature only at the inlet to the primary nozzle of the ejector. The second possible approach is the application of a zeotropic mixture as the working fluid for the conventional ejector cycle. The performance of an EFC is compared to the ejector refrigeration cycle (ERC) working with zeotropic refrigerant. Three motive heat source temperatures (60°C, 75°C, 90°C) and two evaporation temperatures (0°C, 6°C) were tested. Eight pure low-GWP refrigerants and four low-GWP refrigerant blends were analyzed. It was demonstrated that the flash cycle can efficiently operate with low-temperature motive heat source (60°C) with refrigerants R1234yf and R1234ze(E). The highest coefficient of performance (COP) is attainable for propane with a motive source temperature of 60°C and R1234ze(Z) for the motive temperature of 75°C and 90°C. The differences of liquid pump power consumption of both discussed cycles compared to the conventional compression cycle are significant and reach up to 90 percent in the case of EFC and up to 96 percent in the case of the zeotropic cycle. The electric power savings in the case of the zeotropic cycle are slightly higher, but COP and drop of the heating water temperature are notably lower. Therefore, the EFC system is suggested to be a better solution for low-grade heat utilization in the cases when a significant decrease of the motive source fluid temperature is required. [ABSTRACT FROM AUTHOR]

A novel lead-free Ba(1-x)(La,Na)xTiO3 (BLNT), (0 ≤ x ≤ 0.08) ferroelectric ceramic with enhanced energy storage density was fabricated by the conventional solid-state method. With an increase in La3+/Na+ content, the energy storage density, efficiency and power density were increased. The samples with (x = 0.08) show recoverable energy storage of (1.07 J/cm3), 3 times higher than that of pure BaTiO3 ceramics, energy storage efficiency of (87.6%) and power density of 0.314 MW/cm3, 17 times greater than that of pure BaTiO3 ceramics. Comparison with other lead-free ferroelectric ceramics confirmed the superiority potential of (BLNT-0.08) ceramics for the design of ceramics capacitors for energy storage applications. The effect of La3+/Na+ contents on the optical properties of BaTiO3 ceramics was studied via UV spectroscopy. The results revealed that the introduction of structure disorder by means of A-site vacancies leading to the creation of shallow defects resulting in narrowing the bandgap energy. This work may provide a simple and powerful method to develop inexpensive energy storage and photovoltaic devices based on ferroelectric ceramics. [ABSTRACT FROM AUTHOR]

Cloth drying is a major consumer of energy, and most drying is conducted by evaporative methods. The evaporative drying energy efficiency limit is commonly assumed to be 100%: one unit of latent heat removed per unit of energy expended. However, this ignores the "free drying" available from unsaturated ambient air and the possible role of heat pumping. We demonstrate that efficiency limits for evaporative drying are fundamentally related to both drying rate and ambient psychrometric conditions. A relationship among efficiency, drying rate, and ambient conditions is quantified for several evaporative drying technologies, and a comparison among evaporative technologies is provided. In addition, a comparison is provided between efficiency limits and state of the art device performance. This research will help guide future research in the most promising directions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to analyze the effects of electricity price changes and energy efficiency subsidy on household energy efficiency purchase and/or behavioural adjustment decisions. The analysis adds energy efficiency investment to a methodology that merges the physics of energy with microeconomic principles. The physical side informs the amount of electricity used to satisfy services that people desire, while the microeconomic side imposes a utility function that represents a household's welfare. Several electricity pricing schemes and energy efficiency options are examined, with costs and benefits of each option explicitly modeled in the physical representation. Several insights are derived from performing an analysis for archetypical villas across Saudi Arabia. One, energy efficiency purchases lower the need for energy conservation. Households also lessen the extent to which they practice conservation as energy efficiency subsidies are raised. Additionally, as energy efficiency subsidies and electricity prices rise, the difference in household spending on other goods and services widens between the highest efficiency case and no added efficiency. This indirect rebound causes a situation where firms would increase their production, and thus energy use, to meet the additional demand by households for their goods. [ABSTRACT FROM AUTHOR]

A comparative analysis of the Coefficient of Performance (COP) and the Energy Efficiency Ratio (EER), based on the technical data of 430 different models of air-to-water heat pumps (AWHPs) as well ground-source heat pumps (GSHPs), at certain conditions of ambient air, ground source and water outlet from the heat pump (HP) temperatures, is performed. The results, presented in graphical and tabular form, give the COP and EER values against the HPs nominal capacity and the correlation between COP and EER with the temperature rise ΔΤ along the HP. By averaging the performance values of all AWHPs or GSHPs models, equations of polynomial regression that give the relationship between average COP or EER and ΔΤ values were also calculated. It is shown that inverter-driven HPs generally have higher COP and EER as compared to the fix-capacity HPs, for the same heating or cooling range. Also, performance is highly depended on ΔΤ. [ABSTRACT FROM AUTHOR]

The design of an indoor lighting system for a sustainable building should comply with the recommended maximum limit of lighting power density. The occupants' visual comfort and visual performance are to be ensured by complying with some mutually conflicting lighting design parameters, such as maintained average illuminance, overall uniformity, and maximum unified glare rating, to the recommended limits. Judicious balance among these multiple conflicting design parameters is a practical design problem. This article aims to address these aspects of indoor lighting design by applying a particle swarm optimization (PSO) algorithm in a developed lighting computation program. The objective function is formulated with maximum or minimum limits for the design parameters recommended by international standards. The effectiveness of the developed program is evaluated by designing an indoor lighting system with commercially available luminaires for an office space that ensures optimized visual comfort, energy efficiency, and initial cost. Optimized results are validated by DiaLux simulation and a maximum deviation of 2.27% is found. Thus, the results show good agreement with DiaLux simulation and significant improvement in the uniformity of illuminance (0.90) compared to the recommended minimum value (0.70) and in discomfort glare (16) compared to the recommended allowable maximum value (19). The developed program establishes the usefulness of the PSO algorithm to optimize the luminaire layout for an indoor general lighting scheme. [ABSTRACT FROM AUTHOR]

In Canada, the solar electricity sector is growing rapidly. Much of this success is based on the growth of the Ontario solar market where more than 99% of Canada's solar electricity is generated. Ontario has developed a globally recognized solar market sector. The vast surface area of existing residential roofs across Canada represents an untapped resource for capitalizing on passive and active management of impinging solar insolation. The aim of the current research study is to evaluate the new energy harvesting technologies such as a thin-film PV integrated roof system that could serve as a conventional roofing for weather protection while generating clean solar electricity, and the new generation micro inverters that have the potential to outperform string inverters under shading and snow-cover conditions. This paper has two parts that will discuss about two smart energy harvesting technologies and their performance on residential applications in Canadian climate. Part 1 of the paper focusses on field evaluation of Roof Integrated Photovoltaic (RIPV) and Part 2 talks about the energy yield performance of integrated solar tiles and new generation micro inverters. The RIPV field trial took place at the Canadian Centre for Housing Technology (CCHT) Info Centre in Ottawa, Canada. This is a novel approach adapted from a roofing system that would typically be found on low-sloped roofs such as commercial supermarkets, industrial warehouses and school buildings. Over the eight month study period, surmounting the effects of snow cover and shadows, the RIPV system generated over 1 MWh of electricity, and had a measured system efficiency of 5.3%. The study on the new generation micro inverters for residential applications addressed the shading effects on the intermittent nature of solar energy generation. Simulating the shading conditions that are experienced by typical residential rooftop, the micro inverters were found to increase production by 1–68% relative to the conventional string inverters. The research outcome of this study has demonstrated that both these energy harvesting technologies have important incremental benefits in increasing the renewables contribution to power generation in residential homes in Canadian climatic conditions. [ABSTRACT FROM AUTHOR]

Machine tools consume a large amount of energy in the production process. Effective reduction of energy consumption of the machine tool will lead to significant savings. Although substantial efforts have been devoted to reducing energy consumption of the machine tool through upgrading the equipment or improving the manufacturing process, the study of energy efficiency improvement through effective maintenance operations scheduling has received significantly less attention. Power consumption usually increases as the machine tool deteriorates in most mechanical manufacturing environments. In this paper, we develop a discrete-time, discrete-state homogeneous Markov chain of the deteriorating machine tool based on energy efficiency. To evaluate the energy performance and productivity performance of the machine tool with periodic maintenance, analytical models of average energy efficiency and average productivity are developed based on renewal reward theorem. The effects of some parameters on the average energy efficiency are analysed through a numerical example, and the trade-off between energy efficiency and productivity is discussed. [ABSTRACT FROM PUBLISHER]

California is a leader among states in its efforts to cut greenhouse gas emissions. Under the California Global Warming Solutions Act of 2006 (Assembly Bill 32), the state has set itself on a course to reduce its greenhouse gas emissions to 1990 levels by the year 2020. In addition to its cap-and-trade program, California aims to accomplish this objective via a large assortment of complementary and overlapping policies. To a significant degree, cap-and-trade is a market-based “dessert” that follows a multicourse menu of other regulatory initiatives aimed at cutting emissions. The reduced cost-effectiveness, political costs, and regulatory costs associated with this approach make it unlikely to form a suitable model for states in which political commitment to climate action is more limited or regulatory capacity is not as great as in California. [ABSTRACT FROM PUBLISHER]

Many countries are actively trying to cope with recent effects of climate change and the energy crisis. At the same time, efficient energy use and the reduction of greenhouse gas emissions are very important, not only to reduce energy costs but also to contribute to an environment-friendly, sustainable lifestyle. Currently, manufacturing industries in some countries pay stratified electricity rates that depend on the time of the day (i.e. peak load, mid-load and off-peak load). Hence, the production scheduling process, which considers time-dependent and machine-dependent electricity costs, enables these industries to minimise energy expenses. Additionally, the emerging Smart Grid is supposed to require industries to pay real-time hourly electricity costs. More energy-efficient, intelligent production scheduling is thus a major goal. This paper deals with minimising the total production cost of the flexible job-shop scheduling problem. Our method allows each decision-maker in the manufacturing industry to seek a compromise solution for total production costs, by considering electricity costs with distributed energy resources and energy storage. We use constraint programming and mixed-integer programming approaches to solve this problem, and compare our proposed models with the classical computational method. [ABSTRACT FROM AUTHOR]

In this study, energy consumption is simulated for a residential complex in the cold weather condition of Iran. For this purpose, Tabriz is selected as the representative city. The mathematical equations are suggested to connect the consumed energy (such as electricity and gas consumption) with the required parameters including ceiling insulation, wall thickness, and the window height. The validation is applied to check the results via converting the data into neural networks and employing the genetic algorithm at each level of the study. The error between the software results and also the calculation of building gas consumption is about 9.6% in September and October while the error between the regression function and the measured values was less than 6%. The results show that, in the cold weather condition, the power density of equipments and the efficiency of heating system have the most effect on the electricity and gas consumptions, respectively. Also, in the regarding weather condition, window height has negligible effect on electricity and gas consumption. [ABSTRACT FROM AUTHOR]

This research investigates the extent to which the design of different policy instruments directed towards the same goal shape the constituencies of residents that participate in the program, and discusses the implications of these relationships for policy making and policy design. The theoretical focus is on the constituencies of policy takers that respond to differing policy designs. Based on this framing, participation in energy efficiency programs is empirically estimated, including loan, rebate, and audit, in Tallahassee, Florida, at the household level. Examining community characteristics such as racial, economic and demographic characteristics of residents, the study identifies systematic differences in participation across these policy instruments. In conclusion, the article discusses how the characteristics of potential policy takers might align with policy makers' motivations to shape instrument design. [ABSTRACT FROM AUTHOR]

This article analyzes the possibility of substantially reducing greenhouse gases (GHG) in the Mexican industrial sector by applying a Low-carbon (LC) scenario, through a period of 25 years, composed by a set of mitigation options that involve the use of energy efficiency, materials recycling, cogeneration and renewable energy. Results reveal that a GHG peak of 226 million tons of equivalent CO2 could be reached by 2030 with a GHG reduction of 26.5%, compared to a Base scenario, demonstrating that the LC scenario could exceed Mexico's Nationally Determined Contributions objective of reducing 19% of its industrial sector GHG by 2030. Additionally, GHG reduction of 47% could be achieved by 2035. Finally, the economic viability of the LC scenario was evaluated using a cost-benefit approach. As a result, economic benefits above $24,000 million dollars could be achieved due the energy savings generated are greater than costs to implement the mitigation options. [ABSTRACT FROM AUTHOR]

Museums have inherent capabilities, resources, and opportunities that position them to influence public responses to climate change. Using examples from diverse museum-types, Sutton highlights innovative ways in which energy efficient practices and thoughtful approaches to engaging communities with collections, exhibitions and programs can increase climate literacy and call people to action. Sutton argues that these bright spots in the sector's work signal capacity but not widespread commitment. The result is a slow process of aligning resources and talents of museums toward this global fight. During 2020, as the World and the sector reels from the impacts of COVID-19, museum actions mirror many responses appropriate in the climate crisis. Sutton suggests that these build the sector's ability and appetite to help communities. As nations emerge with recovery plans that could create a healthier, more just and resilient society, museums have the opportunity to influence that work, thereby magnifying positive impacts. [ABSTRACT FROM AUTHOR]

This study explores to what extent the development of democracy affects energy efficiency. This study applies database reference from Freedom House, Polity IV project, International Country Risk Guide (ICRG) and World Development Indicator (WDI) to analyze the relationship between the level of democracy and energy efficiency of 35 countries in Europe from 1990 to 2013. Controlling for manufacturing value-added, price level, and GDP per capita, we find a significant statistical correlation between the level of democracy and the level of energy efficiency in a country. Empirical findings show that a high level of democracy has a significant positive impact on the improvement of national energy efficiency. Further examinations which employ quantile regression estimates indicate that the positive impact of democratic consolidation is stronger when the country is at the stage of relatively low energy efficiency. Empirical research also demonstrates that the consolidation of democratic institutions and economic development has a positive influence on the awareness of environmental conservation, thereby improving the structure of energy consumption and further reinforce the enhancement of energy efficiency. [ABSTRACT FROM AUTHOR]

The last global economic crisis set fiscal consolidation as one of the most relevant goals of economic policy. At the same time, efforts are necessary to increase economic growth rates, particularly by increasing quantity and quality of public investment. However, the lack of fiscal space and other impediments make these goals hard to attain. On the contrary, in many countries data show negative dynamics of quantity and quality of public investment. In terms of energy efficiency investment, trends are positive. However, the pace of investment significantly underperforms the goals set. We argue that one of the major reasons is the lack of financial innovation and project selection methodology. For this reason, projects have still been mainly financed under traditional procurement models. Surprisingly, most countries do not exploit the advantages of alternative models of financing which do not affect public debt level, significantly reduce fiscal deficits and reduce fiscal risks. This article argues that a multi-criteria approach used at the initial stages of project preparation increases the potential for project realisation and the overall quantity and quality. In order to provide empirical evidence, we use information on energy efficiency streetlighting projects and present a case of a traditional versus alternative financing models. a need for a systematic approach when selecting optimal financing model is a must; a lack of financial innovation is one of the most critical impediments to a higher level of investment in revenue-generating projects common for the energy efficiency sector; alternative models of financing enable public investment increase without harming the fiscal position; a new methodology for selecting the most preferable model is presented; a policy mix should take more comprehensive stance towards complexity of public investment projects. [ABSTRACT FROM AUTHOR]

Floating production storage and offloading (FPSO) platforms are great energy consumers. Reservoir fluid composition and operating parameters of FPSOs are known to be important parameters for the total energy demand, and also for enhancing overall oil production. In the current research paper, the contribution of eight thermodynamic input parameters of a typical Brazilian FPSO operating on a pre-salt field is quantified by the Smoothing Spline ANOVA method for two responses: (i) energy consumption of the plant and; (ii) overall oil production. Three operation modes are considered in the analysis: Mode 1 (maximum oil/gas content), Mode 2 (50% BS&W) and Mode 3 (maximum water/CO2 content). The input parameters considered in the present research are: output pressure of the first control valve (P1), output pressure of the second stage of separation train (P2), input pressure of the third stage of separation train (P3), output pressure of dilution water pump (P4), output pressure of the main gas compressor (Pc), petroleum temperature of the first heat exchanger (T1), petroleum temperature of the second heat exchanger (T2), and dilution water temperature of heat exchanger (T3) are considered as input parameters. In terms of energy consumption, parameters P3 and Pc are always relevant for all operation modes. Furthermore, P3, P2, and T2 are the most important parameters for overall oil production for all operation modes. [ABSTRACT FROM AUTHOR]

Enhancement of buildings energy efficiency has typically been approached by viewing the buildings from a social acceptance perspective focusing on multi-level stakeholders. In order to examine social acceptance in terms of public's opinion and knowledge about using low carbon buildings, a multiple-choice questionnaire was designed with four groups of questions: background information, community perspective, social perspective, and market perspective. The study showed that 59.72% of the seventy respondents' opinion were using low carbon building (LCB) can help to reduce greenhouse gas emissions. In general, more than 53% of the respondents were willing to upgrade their accommodation to LCB. However, 70% respondents were not ready to hire any consultant because majority of have the problem in paying the upfront cost for LCB. [ABSTRACT FROM AUTHOR]

This work presents the evaluation of the downlink (DL) performance of a dual-layer cellular networks by using energy efficiency (EE) metric, where femto base stations (FBSs), macro base stations (MBSs) and users (FUs) form independent spatial Poisson point processes (PPPs). The proposed network model is developed by considering number of antennas at each BS alongside a single antenna at each user with the use of the conventional spectrum re-utilization approach. Then, Coverage probability and EE expressions for the dual-layer cellular networks are exclusively derived analytically. It is also demonstrated that simulation results are almost inline with the analytical one in the PPP-based model. While coverage probability deteriorates with less margin in the lower FBS density region compared to the scheme presented in Xu and Qiu ["Energy efficiency optimization for MIMO broadcast channels," IEEE Trans. Wireless Commun., Vol. 12, no. 2, pp. 690–701, Feb. 2013.] signalled not much turnaround of the network performance, EE in the lower and the upper FBS density regions are likely to remain between 6 × 10 − 3 to 9.2 × 10 − 3 Bits/Joule and 4.6 × 10 − 3 to 7.1 × 10 − 3 Bits/Joule, respectively. Proposed scheme tells us that it is firmly on course to match up with Vehicular Ad-hoc NETworks (VANET) applications without incurring high cost as EE, low latency, coverage probability and low power adaptability are back on good growth path. [ABSTRACT FROM AUTHOR]

The ergogenic effects of citrulline malate (CitMal) and beetroot juice (BEET) have been widely studied, but their effects on physiological outcomes related to resistance exercise are not fully understood. The purpose of this randomized, double-blind, crossover study was to investigate the effects of CitMal (8 g) and BEET (400 mg nitrate) on blood pressure (BP), blood flow, and energy efficiency during submaximal leg extension. Recreationally active males (n = 27; age: 22 ± 4 yrs) completed familiarization, followed by three testing visits. Supine and standing BP were measured upon arrival, followed by supplement ingestion, a 2-h rest period, postsupplement BP measurement, and a bout of repeated submaximal isotonic leg extensions at 25% of maximal voluntary contraction torque. Diameter (aDIAM) and blood flow (aBF) of the superficial femoral artery, and cross-sectional area (CSA) and echo intensity (EI) of the vastus lateralis, were measured before and after exercise via ultrasonography. Muscle blood flow (mBF) and oxygen consumption (mVO2), along with whole-body energy expenditure (EE) and respiratory exchange ratio (RER), were measured before and during exercise via indirect calorimetry and near-infrared spectroscopy. Baseline RER values differed among treatments (p = 0.01); BEET was higher than CitMal (p = 0.01) but not PLA (p = 0.58); CitMal and PLA were not significantly different (p = 0.12). No other measurements were significantly affected by treatment (all p > 0.05). Results suggest that neither CitMal nor BEET significantly influence resting BP, blood flow, or metabolic efficiency during submaximal leg extension in recreationally active males. [ABSTRACT FROM AUTHOR]

In this paper, we propose an energy-efficient resource allocation algorithm in the downlink of a multicell large-scale distributed antenna system. A non-convex optimization problem is formulated to maximize the energy efficiency (EE) of the entire network. The optimization problem considers the circuit power consumption, the minimum data rate requirements, and the maximum allowed transmit power per remote radio head. The optimization problem is transformed into an equivalent optimization problem in the subtractive form using the Dinkelbach method. An iterative algorithm for the optimization solution is proposed in which antenna selection with user scheduling and power allocation are implemented separately. To tackle this significant computational complexity, a norm-based joint antenna and the user selection algorithm that uses Tabu Search are proposed to select optimum antennas and users for transmission. Next, a Lagrangian dual decomposition method is adopted to derive a power allocation strategy that can run independently in each cell. Simulation results show that the proposed algorithm can achieve its maximum EE in several iterations, and that increasing the number of antennas or users does not necessarily result in a higher EE. In addition, the proposed iterative scheme is always able to achieve a better performance than the traditional norm-based algorithm and the simplified cloud radio access network based energy efficient power allocation scheme, no matter how many antennas or users are selected. [ABSTRACT FROM AUTHOR]

The present current study aimed at analyzing the input–output energies and optimizing energy efficiency and greenhouse gases (GHG) in crops production at the northeast of Iran. The results of this research showed that the total energy inputs were equal to 42.4, 28.6, and 72.8 GJha−1 for, wheat, barley, and sugar beet, respectively. It was also shown that the highest energy efficiency, the lowest GHG emissions, and GHG intensity all belonged to barley production. The highest percentage of GHG intensity pertained to sugar beet production (41%), which was followed by wheat (38%) and barley (21%). It was also revealed that GHG intensity is a better criterion for the study of GHG since it also makes use of the energy output information in crops. The optimal model responses for the crop type and proper cultivation planning was 284432 hectares in terms of barley production, while those responses for wheat and sugar beet were zero and, thereby, they were eliminated from the model of Multiple Goal Programming (MGP). In the same way, this model could increase energy efficiency to 444875, while GHG emissions and its intensity decreased by 213259 tonCO2eq and 1.3 tonCO2eq MJoutput−1 per year, respectively. [ABSTRACT FROM AUTHOR]

In this study, to meet the electrical load requirement of Yalova University campus, grid-connected hybrid power generation simulations, and grid-independent hybrid power generation simulations were made with the Hybrid Optimization Multiple Energy Resources program. Eight alternative scenarios have been surveyed by employing annual solar radiation and wind speeds, fuel cost parameters, and energy storage need of the campus. Photovoltaic panel/wind turbine/diesel generator/battery/converter is proposed in hybrid energy system scenarios. In the analysis, net present value, cost of energy per unit, emission values, renewable energy rates and sensitivity analysis are calculated and presented in figures and tables. The energy production using renewable energy sources at 61.6%, 65.4% and 75.2% and the systems without renewables were investigated. As a result of the study, it was determined that the emission of the case whit 0% renewable energy is 7.3 times higher than the case with 75.2% renewable energy used. It was seen that the emissions of the scenario with 75.2% renewable energy used are 1.56 times less than the scenario with 61.6% renewable energy used. [ABSTRACT FROM AUTHOR]

The main source of building energy consumption in Iran is fossil fuels. The building sector, as a result, is responsible for a high share of CO2 emissions in this country. To address the issue, the government has recently adopted the “green management system” policy in order to alleviate the severe rate of CO2 emissions from the government buildings. As a commitment to the policy, the University of Tehran plans to transform into the first green university of Iran through green retrofitting in the coming years. As the first step to the retrofitting process, this paper measures the potential of energy-saving and CO2 emission reduction in the University of Tehran Science & Technology Park (UTSTP) offices with the use of Building Information Modeling (BIM). For this, Building No. 2 of UTSTP is modeled in the environment of DesignBuilder software to provide a calibrated computational model for energy and carbon audit. A detailed audit is then conducted using the calibrated model to identify the major areas of energy loss in the case study. Based on the audit results, several green strategies are then proposed to improve the weak performance of building in the identified areas. The strategies include triple glazing windows, aerogel envelope, phase change material (PCM) insulation, and Trombe wall. Findings suggest that the thermal loss from the building structure as a result of insufficient levels of insulation in the building components is the main source of energy loss in the building. Simulation results show that green strategies to a large extent have good energy-saving and mitigation potential. Full implementation of the proposed green strategies would reduce the annual heating needs and CO2 emissions of the case study by 51.6% and 5.39% respectively. [ABSTRACT FROM AUTHOR]

This paper discusses integration of twenty-first-century direct-exchange geothermal technology with nineteenth-century heat supply infrastructure to provide climate control at The Breakers, Newport, Rhode Island, U.S.A. In 1892, Cornelius Vanderbilt II built an 11,600 m2 Italian Renaissance style summer residence equipped with the most modern domestic technology available. This house retains original architectural finishes, furnishings, and a decorative arts collection, to give visitors insight into America's Gilded Age. The mansion's original design relied upon the ocean setting for its natural ventilation during summer occupancy; a convection heat system maintained the building through winter. A century later, risks to the collection due to extreme fluctuations in temperature and relative humidity along with rising energy costs prompted a climate modification feasibility study. The expense and complexity of conventional systems were deemed prohibitive, intrusive, and unsustainable. A high-efficiency geothermal heat pump system was chosen because it could generate conditioned, filtered air, re-use historic convection heat shafts, and significantly offset heating costs. Since going online in 2018, the system has stabilized the interior environment and considerably reduced fuel consumption. Discussion will include challenges encountered through design, installation and start-up, and assessment of environmental data. [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the thermal performance of a box-type solar cooker (BTSC) by implementing two Fresnel lens magnifiers (FLMG) which concentrate the solar irradiance on to the cooker surface. A comparison in thermal performance was done in the presence and absence of the Fresnel lens magnifier. Three main tests, namely, stagnation test, load test, and cooking power test were conducted for determining the performance. It was seen that the first and second figure of merit increased from 0.11 to 0.12ᵒCm2/W and 0.43 to 0.45 respectively in the presence of the Fresnel lens magnifier. A linear regression analysis of the plotted points was used to develop a relationship between standardized cooking power and temperature difference and the cooking power for a temperature difference of 50ᵒC was calculated. The cooking power enhanced from 43.83 W to 46.87 W at the temperature difference of 50ᵒC by the usage of the magnifier. The average value of transmittance for the magnifier was 72.26% for the solar energy spectrum. The geometrical concentration ratio was increased by 48.7% by incorporating the Fresnel lens magnifier. The average value of energy efficiency of the solar cooker was calculated and was found to increase from 29.6% to 32.04% by adding the Fresnel lens magnifier. [ABSTRACT FROM AUTHOR]

Most experts agree that the greatest risk associated with climate change is pretending that the problem does not exist, or that it does not require immediate attention and action. That said, the potential pathways for mitigating the effects of greenhouse gas emissions are not created equal in terms of the risks and benefits they entail. Public discourse tends to focus on the most optimistic scenarios for implementing new technologies and to ignore not only the hazards but also the non-climate-related benefits associated with some approaches. Climate mitigation strategies currently undergo economic and engineering analyses, but they are not consistently subjected to rigorous risk assessment and risk management. The author offers the beginnings of a more cohesive decision-support analysis framework. Assessments of various mitigation strategies by the world’s largest industry—insurance—are critically important in this process because insurers can provide a dispassionate view and internalize the costs of risk through pricing. Bank financing cannot be mobilized without insurance, and the public sector may be forced to assume many of the risks associated with emerging technologies if insurers opt out. A century of dangerously blending technological enthusiasm with lack of care in assessing the comparative risks of energy and land-use choices ushered in today’s climate crisis. Continued inattention threatens to saddle society with new risks from poorly prioritized efforts to solve the climate problem. Procrastination is painting humankind into a corner in which progressively riskier and unproven technologies will be required to mitigate climate change. [ABSTRACT FROM PUBLISHER]

Nuclear exit has been on the German policy agenda for more than three decades. After the Chernobyl accident in 1986, a majority of the public and relevant stakeholders opposed nuclear power and strove for renewable energy alternatives. At the same time, climate change policy gained the attention of German policy makers, and they approved ambitious targets for the reduction of greenhouse gas emissions. In 2000, the federal government and the operators of nuclear power plants reached a phase-out agreement, and since 2002, the purpose of the Atomic Energy Act has been not the promotion but the phasing-out of commercial nuclear electricity generation. After the federal elections in 2009, the conservative–liberal coalition government implemented a slow-down of the phase-out. But that reversal provoked strong negative public reaction, and in response to the nuclear disaster in Japan, the German cabinet and the Bundestag agreed in the summer of 2011 to a gradual phase-out of nuclear power that will shut down the industry by 2022. They also agreed to accelerate the transformation of Germany’s energy portfolio. This transformation, or Energiewende, will include three key methods of replacing the electricity once produced by nuclear reactors: It will expand renewable energy production and provide the infrastructure needed for that expansion; it will significantly improve the country’s energy-efficiency efforts; and for a transition period, it will also encourage the construction of new and more efficient coal- and gas-fired power plants. Already, the Energiewende has observably decoupled energy supply from economic growth, with Germany’s energy supply and carbon-dioxide emissions dropping from 1990 to 2011 as its gross domestic product rose significantly. It is this evolving Energiewende, rather than the nuclear phase-out, that will require and, perhaps, inspire continuing reforms of social, economic, technological, and cultural policy in Germany. [ABSTRACT FROM PUBLISHER]

Drip fertigation has potential to reduce fertilizer dose in comparison to surface application in coconut (Cocos nucifera L.) by increasing its’ use efficiency in the Eastern Gangetic plains of South Asia. A long-term field experiment (2007–2013) was conducted on Inceptisol to evaluate 100% of the soil test-based recommended fertilizer dose (RDF; N:P2O5:K2O applied at 500:250:750 g palm−1 year−1) in soil with ring basin irrigation as conventional, 100%, 75%, 50%, 25%, and 0% of the RDF through drips. The fertigation level of 75% RDF resulted in 32%, 19%, 39%, and 16% higher copra yield, energy productivity, net return, and benefit-cost ratio, respectively, over conventional. Increasing trend of nutrient use efficiency was observed with decreasing dose of N, P and K. Use efficiencies decreased from 50.4 kg copra kg−1 N, 230.7 kg copra kg−1 P, and 40.5 kg copra kg −1 K (with 25% of the RDF through drip) to 6.1 kg copra kg−1 N, 27.8 kg copra kg−1 P, and 4.9 kg copra kg−1 K (with 100% RDF through ring basin irrigation). Fertigation with 75% RDF in drip had the highest copra yield (3.19 t ha−1), energy output (206082 MJ ha−1), energy productivity (187 g copra MJ−1), net returns (US $ 3073 ha−1), and benefit–cost ratio (2.36) compared to others. [ABSTRACT FROM AUTHOR]

Aims: This study aims to compare the total heart beat index (THBI) in evaluating energy efficiency between using a manual wheelchair and walking for children with cerebral palsy (CP). Methods: The energy efficiency was measured in 21 participants with CP (mean age, 13.6 ± 3.4 years) who walk or drive a manual wheelchair using a square course. THBI was calculated as total number of heart beats during the exercise period/total distance traveled. Results: Significant differences in the THBI were observed between Gross Motor Function Classification System (GMFCS) levels III and IV (p =.049, effect size = 1.60). No significant differences in THBI were observed between GMFCS levels II and III or between GMFCS levels II and IV (p >.05). Conclusions: The energy efficiency of children with CP who use a manual wheelchair in this study was equal to or better than that for walking. [ABSTRACT FROM AUTHOR]

Waste collection is a daily operation common to all cities. Nonetheless, the energy-saving potential, and thus the greenhouse gas and air pollutant emissions, of such collecting process are still hardly addressed in the literature. This study assesses, considering the bottom-line of sustainability, a broader range of eco-driving techniques applied to the urban waste collection trucks' fleet of a municipal urban cleaning company, in Rio de Janeiro, Brazil. Eco-driving training was offered to 22 drivers in a fleet of 11 trucks, which operate in two different scenarios: a stop-and-go cycle and a transfer operation to a single delivery point. As results, eco-driving techniques provide economic returns according to the mileage driven. The practice not only has effects on fuel economy, up to US$18,507.55 per month for a fleet of 43 vehicles, but also mitigates 7.1% of CO2-e emissions and local air pollutants. [ABSTRACT FROM AUTHOR]

Hydropower development on gravity-based drinking water supply pipelines in India has not been widely practiced, even at the micro-hydropower (MHP) scale. Site visits including measurements of pipeline flow and pressure were conducted at 12 schemes in Uttarakhand, and 3 were chosen for detailed analysis. Due to a complete lack of existing pressure control, the available drinking water flow would have to be reduced to enable retrofitting with MHP turbines. Technical and economic calculations were performed for a hypothetical 20% flow reduction, but showed electric power yields between just 1.2 and 3.9 kW and long payback periods between 8 and 24 years. The favoured alternative proposal is to incorporate the planning of MHP facilities into the inevitably necessary renovation and/or expansion of pipelines to both (1) meet future water demand and (2) enable the development of MHP. This hypothetical improved case showed an increase in electric power yield by a factor of 5 over the retrofitting case, and was recommended to the state water utility Uttarakhand Jal Sansthan. [ABSTRACT FROM AUTHOR]

Programs to improve the sustainability of building infrastructures often consist of project portfolios that need to be prioritized in an appropriate chronological fashion to maximize the program's benefits. This is particularly important when a revolving-fund approach is used to leverage savings from the initial projects to pay for later improvements. The success of the revolving-fund approach is dependent on the appropriate prioritization of projects. Competing performance measures and scarce resources make this task of project prioritization during the planning stage a complex and challenging endeavour. The current study examined the impact of different project prioritization strategies for revolving-fund sustainability program performance. A novel modeling approach for sustainability decision-analysis was developed using the system dynamics method, and the model was calibrated using a campus sustainability improvement program at a major university. The model was applied to evaluate the effects of five common project-prioritization strategies on three program-performance measures, across a wide range of initial investment levels. For the university case study, we found that the strategy of prioritizing projects according to decreasing benefit/cost ratio performed best. The research demonstrated that using a system dynamics model can allow sustainability program managers to make better-informed sequencing decisions, leading to a financially and environmentally successful program implementations. [ABSTRACT FROM AUTHOR]

Nowadays, the demand for a finer grind in mineral processing has set new challenges within the industry, particularly for grinding technology. Apart from a finer grind, energy efficiency is also a key driver in optimizing grinding technology. With increasing need for fine and ultrafine grinding, stirred media mills became an alternative for conventional ball mills. In this study, samples of bauxite whose chemical composition and Hardgrove Index values are known were ground to micronized size by a laboratory scale stirred media mill and its performance was compared with a laboratory scale ball (Bond) mill. Stirred media mill decreased bauxite d50 size from 780 to 5 µm in 3 min. But, the ball mill has reduced to 455 µm at the end of the same grinding period. In addition, the energy consumed by the ball mill for similar fineness (5 µm) was approximately 300 kWh/t energy, whereas the stirred media mill consumes approximately 174 kWh/t energy. As a result, the stirred mill consumed less energy because it could grind in a shorter time. [ABSTRACT FROM AUTHOR]

Energy efficiency is not only the most cost-effective way to reduce carbon dioxide emissions but also a way to improve competitiveness and create employment. EU aims to achieve nearly zero-energy (public) building (NZEB) by the end of 2018 (2020 for private buildings). This very ambitious target would be more easily fulfilled if high-performance thermal materials like phase change materials-PCMs are to be used. This paper reports experimental results on the properties of fly ash-based alkali-activated binder-AACB mortars in which a minor percentage of aggregates were replaced by PCMs. These include compression strength, at normal temperature and also at high temperatures, flexural strength, density, water absorption, unrestrained shrinkage as well as cost analysis. Several AACB mixtures showed an increase in compressive strength after being exposed to high temperatures. Since PCMs are made of flammable materials and AACB mortars show a much higher stability at high temperature than Portland cement-based mortars this means that AACB mortars are more suitable for PCM incorporation. This is a very important feature because flammable insulation materials were reported to be the cause of the recent Grenfell Tower fire tragedy that made 71 victims. [ABSTRACT FROM AUTHOR]

This paper presents a game-theoretic scheme with anti-coordinated players by incorporating adaptation of femto base station (FBS) transmit power, attenuation of interference and utility function for open access mode and closed access mode, respectively. The deployment of femtocells in the networks is to produce improved energy efficiency (EE) and optimized response of payoff function. Additionally, the operating principle of the spectrum sharing scheme has been discussed in which FBS as a player acquire knowledge from utility responses of their strategic communications and revise their strategies at each level of the game process. Here, an FBS is regarded as a player in the game to select those users who are satisfied to a greatest extent and besides an FBS plays a role of mentor. Thereafter, the equilibrium concept has been invoked to aid the anti-coordinated players for the strategies. Finally, validated the simulation results are with its rarely studied extension in cognitive-femtocell networks. [ABSTRACT FROM AUTHOR]

This article presents a differential evolution (DE) algorithm that can be used to plan public lighting for streets, roadways, and freeways and maximize the energy efficiency of the installation. The algorithm was applied to a model based on new relationships between the energy efficiency of street lighting systems and geometric parameters such as street width, luminaire height, and distance between poles. These relationships were derived from the regression analysis of a large sample of outputs. The results of this algorithm consisted of the luminaire arrangement (one-sided, two-sided staggered, and two-sided coupled), luminaire height, luminaire type, and pole spacing for the most energy-efficient installation. The input of the algorithm was the lighting class or illuminance level, street width, as well as various other luminaire parameters. When these results were compared with those of DIALux, the performance of this new method was found to be extremely satisfactory. Furthermore, the constraints applied guaranteed compliance with the recommendations of the International Commission on Illumination. [ABSTRACT FROM AUTHOR]

In order to help answering the question 'Which electrode design is the best?', the precipitation performance of a tubular electrostatic precipitator was determined for different electrode designs with special attention to specific energy consumption. Experiments were conducted in a wire–tube arrangement with a high loading of liquid submicron particles causing strong space charge effects, also known as corona quenching. The experiments are supplemented by numerical simulation results showing the effect of residence time and power consumption on separation efficiency. [ABSTRACT FROM AUTHOR]

Today, timber trucks of gross vehicle weight (GVW) up to 76 tonnes are allowed to operate on Finnish roads from roadside landings to mills. Reducing trucking costs and exhaust gas emissions have been the dominant reasons for the increased GVWs of timber trucks. A discrete-event simulation (DES) method was used to compare the impact of the truck and payload size, trucking distance, and timber assortment lengths on trucking performance indicators (e.g., productivity, energy efficiency, and costs of trucking) in the procurement area of a case logistic company operating in Central Finland. The studied truck sizes were 68, 76 and 84 t, of which the 76-t trucks dominate timber trucking in Finland. Over a transport distance of approx. 105 km with an average assortment length of 4.2 m, 76-t trucks had 9% higher and 12% lower productivity (m3/100 km), 1% lower and 4% higher fuel consumption (l/m3) and 4% lower and 6% higher trucking cost (€/m3) compared to 68- and 84-tonner options, respectively. The improvement in regards to previous indicators was clearly bigger for the 76-tonner than the 68-tonner if the trucked wood assortments were lengthened to 5.0 m. The differences in cost and fuel efficiency as well as annual trucking volumes were increased as a function of the trucking distance, when comparing the truck configurations with different GVWs and payloads. To conclude, the tendency of the size increase in GVWs in timber trucking in Finland can be justified in light of the study results. [ABSTRACT FROM AUTHOR]

In the present work, a sensible heat storage system with multi-tubular cavities is tested. Heat storage system having a capacity of 8 MJ is made of concrete and air is selected as heat transfer fluid. The diameter of the cylindrical heat storage system is 0.29 m which contains multiple tubular cavities each having diameter of 0.019 m. It is observed that the effect of mass flow rate on different parameters is found negligible beyond 0.029 kg/s. The maximum energy efficiency of the fully charged system corresponds to the maximum mass flow rate while fluid enters at minimum temperature. Sensible heat storage at fluid flow rates of 0.029 kg/s and 0.031 kg/s are in close approximation irrespective of the fluid temperature. [ABSTRACT FROM AUTHOR]

Managing household electricity consumption plays an important role in the overall energy management spectrum. This paper presents an analysis of the main factors that contribute to household electricity consumption. Emphasis is given on consumer behaviour in relation to household characteristics. For this purpose, primary data is collected via a survey study from a representative sample of households. The data were analysed using correlational as well as regression analysis methods. It was found that electricity consumption is a social phenomenon, with economic and technological dimensions. Further, it was verified that energy-saving techniques such as insulation, modern building materials and renewable energy make a significant difference in the electricity cost. Moreover, specific types of electrical appliances are highly correlated with electricity consumption. [ABSTRACT FROM AUTHOR]

Event-driven optimal control was recently developed for central air-conditioning systems to speed up the response of optimal control to irregular changes in the system optioning conditions. In a time-driven paradigm usually, the optimization is carried out with a constant frequency, however the event-driven optimal control triggers optimization actions by events, which will be essentially defined to catch up with the irregular changes. Considering that the occurrence of events should imply the necessity to execute optimization, this paper investigates the necessity of optimization actions, based on which a new method to develop event-driven optimal control law is proposed. This can naturally lead to the establishment of an event-action map. This map indicates that not all the decision variables should be optimized when an event occurs, different from other methods that require optimizing all decision variables. The merits of the new method were also demonstrated using several case studies. [ABSTRACT FROM AUTHOR]

Current clothes drying technology is an energy-intensive process that involves blowing hot air across tumbling wet fabrics to evaporate water. To address the relatively low energy efficiency of this drying technique, a new cloth drying technology was proposed in our prior study. This technology utilizes high frequency ultrasonic vibrations to extract water from a fabric in the liquid phase, resulting in a dramatical reduction in energy consumption and drying time. A piezoelectrically actuated transducer was designed and fabricated. The transducer design was based on a piezoelectric actuator that excites axisymmetric resonant modes in a thin circular metal mesh. The device was constructed by bonding a piezoelectric ring to a thin metal mesh with a hole diameter of 120 µm. Test results demonstrated that the new ultrasonic transducer efficiently dried clothes at an order of magnitude lower resonant frequency compared with the previous commercial devices, 23 kHz versus 135 kHz. Also, the power consumption per area of the new transducer was an order of magnitude less than the commercial devices. Depending on operating conditions, the device was 3–24 times more efficient compared to the commercial ultrasonic transducers utilized in our prior ultrasonic clothes drying studies. [ABSTRACT FROM AUTHOR]

Heating and cooling in high-rise buildings devour about one-third of overall energy consumption. Skycourts is increasingly integrated in high-rise buildings, in particular offices. Skycourts are perceived as transitional and social nodes. This paper aims to investigate potentials of a skycourt when perform as a ventilated buffer zone in offices in a temperate climate. Using a hypothetical office building in London, a coupled approach of energy simulation and CFD was carried out for two ventilation modes; air-conditioned skycourt, and alternative models that incorporate combined ventilation strategies with the adjacent offices' zones of the skycourt. Furthermore, to determine the most critical ventilation conditions, different parameters were investigated. Overall, the results highlight that the incorporation of a ventilated skycourt potentially has a significant impact on the annual energy consumption. The optimized parameters enhance comfort temperature ranges of skycourts. Finally, the study developed guidelines to define the most effective configurations of ventilated skycourts. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the energy flow, GHG emissions, and global warming potential (GWP) in corn production in western Iran. The Data was collected by split plot Design based on randomized complete block design with four replications. The treatments consisted of a combination of three levels of the main tillage factor including conventional tillage (CT), minimum tillage (MT), no-tillage (NT), and three levels of chemical fertilizer including no fertilizer or N0P0K0 (NPK)0, N50P50K50 (NPK)50 and N100P100K100 (NPK)100. The results of this study showed that the total input energy in CT systems, MT, and NT was 56113.24, 51403.70, and 49144.45 MJ ha−1, respectively. The output energy in this tillage systems was 111989.11, 113312.80 and 109516.68 MJ ha−1 respectively. By reducing the rate of fertilizer, the amount of input and output energy was decreased. The NT and MT systems had higher energy efficiency than the CT one. Energy efficiency in (NPK)0, (NPK)50 and (NPK)100 was calculated to be 2.62, 2.53, and 1.88, respectively. The highest amounts of CO2, N2O, and CH4 were observed in corn production with CT systems. In no-fertilization treatments, GHG emissions were also lower. Moreover, the results showed that by decreasing tillage and increasing amount of fertilizer, GWP decreased. According to the results of this study, changing the practice of tillage from CT to MT and reducing fertilizer amount could increase energy efficiency in the region and reduce GHG emissions. [ABSTRACT FROM AUTHOR]

The objectives of this study are to provide new insights on (i) the drivers of changes in final energy consumption in Italy over the period from 1995 to 2015 by employing a multi-sectoral decomposition analysis approach – Logarithmic Mean Divisia Index I (LMDI-I); and (ii) the progress of Italy toward the indicative energy efficiency and mandatory energy-saving targets set for 2020. The decomposition results show that from 1995 to 2015, an increase in final energy consumption caused by activity effects has been almost totally offset by structural changes. Energy intensity improvements occurred during the period from 2006 to 2015 when most of the energy efficiency policies in Italy were implemented. However, unlike the ex ante estimates of energy savings reported by the Italian government, the LMDI-I analysis shows that Italy is not on track to achieve the 2020 energy efficiency and energy-saving targets. Challenges and opportunities in policymaking are discussed. [ABSTRACT FROM AUTHOR]