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Although the nexus between urbanization and energy efficiency has been evidenced at the macro level, we have less knowledge about the effects of administrative level of cities on energy efficiency. Understanding this impact mechanism is necessary to achieve goals of energy conservation and sustainable development. We estimate the relationship between the administrative level of cities and energy efficiency in China by adopting the province-level fixed-effect models from a panel dataset. The empirical findings present that energy efficiency of capital cities is 0.46 (95% Confidence Interval: −0.713, −0.206) lower than that of general cities. Moreover, these effects of administrative level are more substantial in underdeveloped cities. These findings suggest that more political sources and autonomy in the higher-level cities might lead to low energy efficiency. [ABSTRACT FROM AUTHOR]

Multi-core architectures have grown to be a popular choice for deploying Mixed Criticality Systems (MCS). The focus of research in MCS has been to provide timing assurances for jobs with different criticality levels. Due to their significant processing demands and energy-aware/constrained nature, energy conservation in these systems is becoming mandatory. This article presents, mcDVFS, an energy management technique based on Dynamic-Voltage-and-Frequency-Scaling for multi-core MCS. mcDVFS achieves significant energy reduction while maintaining timing guarantees. It also prioritizes quality of service whenever feasible. Extensive experimental simulations show energy savings of ≈ 52% and 34% when compared to EDF-VD and EDF-VD with QoS. [ABSTRACT FROM AUTHOR]

The Wireless Sensor Networks (WSNs) are mostly used for applications which hardly have human interaction and WSN is always known for its limited-energy issue. The wireless sensor nodes are equipped with an in-built power supply and have limited energy to complete their assigned tasks in WSNs. Therefore, for WSNs designing energy-efficient protocols is always been a challenging task for researchers. In this paper, we have studied and discussed various WSNs' existing protocols highlighting their merits and demerits. We have also made a comparative study on different parameters and methodologies followed by the respective references while designing different energy-efficient WSN protocols for different scenarios. [ABSTRACT FROM AUTHOR]

In Syria, the war's devastating destruction to the built environment, especially to the housing and energy sectors, has mounted the demand for energy-efficient social housing. Hence, the implementation of the housing energy efficiency law, endorsed by the Syrian government (Law No. 18, 2009), has had tremendous barriers. The law has not adopted an energy efficiency strategy and plans that comprise; financial provision, assessment framework, fiscal inducements, market initiatives and international collaboration. The present research attempts to assess the improvement potential in the operational energy performance of typical mid-rise residential buildings in Damascus through the implementation of energy conservation housing law and analysis of the key influencing variables. The research evaluates a pilot energy-efficient complying building compared to typical conventional one, in terms of thermal performance, operational energy efficiency, carbon dioxide emissions, and total energy-cost trade-off. The framework, developed by this study, tackles the implementation barriers and divides responsibilities among the involved parties along with the financial and managerial requirements. This is essential, in the light of the Government's self-efforts for reconstruction. The framework enables designers and decision-makers to start thinking from the occupancy stage backwards to benefit the early design stage where irretrievable decisions are being made. [ABSTRACT FROM AUTHOR]

This paper uses spatial econometric and the threshold effect models to study the effects of foreign direct investment (FDI) in China's energy conservation and emissions reduction. We use provincial-level data on pollutants (CO2, wastewater emission, exhaust emission, and waste emission) available from 2001 to 2015. Results indicated that FDI not only promotes China's "energy conservation," but also improves China's CO2 emission efficiency and environmental efficiency. We find that export-oriented foreign companies can significantly improve China's energy efficiency and water quality. FDI enhances energy efficiency through eco-oriented technological progress and water quality, air quality through production-oriented technological progress. We also find that the impact of FDI on China's energy conservation and emission reduction has significant threshold effects. Our findings contradict the often believed "pollution haven hypothesis." [ABSTRACT FROM AUTHOR]

This work proposes a novel cooling system of the inlet air for industrial applications in the hot climates using organic phase change material. This cooling system consists of an inductive fan, an underground heat exchanger including double pipe phase change material. A three-dimensional transient simulation was developed to predict cooling capacity (temperature drop) using the analytical solution method within the MATLAB open-source code software. A prototype of the system was designed, built and tested in laboratory conditions to validate the modeling results. The experimental setup shows an average temperature reduction of 6°C in the air-cooling system in nine working hours, which matches with the simulation results with a variance of less than 2%. Further simulations demonstrated that an industrial scale could reduce the average temperature of intake air to 10°C in 7 hours working. The offline analysis proved a significant energy conservation opportunity in power plants. This study showed that energy performance and power generation of an industrial-scale gas turbine can be improved by 1% and 1.2 MW, respectively. [ABSTRACT FROM AUTHOR]

Energy efficiency factors in building codes and standards are crucial components that are prescribed to buildings to augment their energy efficiency. The objective of this study was to prioritize these vital energy efficiency factors. The present study derives its motivation from energy design and execution professionals, who face the challenge of selecting certain energy factors that may result in a trade-off over other factors. A fuzzy set theory with a decision-making trial and evaluation laboratory (DEMATEL) methodology was employed to obtain the results. A ranked list of prioritized energy efficiency factors is one of the key contributions of this research. We demonstrate that energy efficiency factors can be evaluated according to the degree of their importance. Based on the results, it was concluded that outdoor and indoor climatic conditions, air conditioning systems, orientation of buildings, and ventilation are the four most significant and highest-ranked factors that affect the energy efficiency of a building. [ABSTRACT FROM AUTHOR]

This study applies the slack-based measure-data envelopment analysis (SBM-DEA) method to measure energy efficiency and tests the spatial spill-over effects of fiscal decentralisation, industrial structure and energy efficiency using the spatial Durbin model. The results show that China's energy efficiency presents a clear geographical step distribution, and the Eastern and Western regions have higher energy efficiency than the Central region. Fiscal decentralisation has a positive effect on the energy efficiency of the Eastern and Central regions by upgrading the industrial structure. In addition, fiscal decentralisation has significant, positive externalities on the surrounding areas, promoting environmental protection and energy conservation in all regions of China. The results are in line with the tenets of environmental federalism (Oates & Schwab): through the allocation and transfer of industrial factors, fiscal decentralisation affects energy governance. Therefore, local governments should formulate policies and targets according to their regions' different economic development levels, and the Central and Western areas, which have greater space for improvement and low energy efficiency, should receive attention to balance regional differences. [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]

It is widely recognized that the actual impact of low-carbon technologies is often lower than predicted by models alone, a phenomenon which has been coined the 'performance gap'. Despite this awareness, in many instances estimates of both energy savings and renewable energy generation in domestic buildings continue to rely on engineering models and building energy simulations rather than approaches that are based on measured parameters. Much of the existing literature on the performance gap focuses on energy efficiency and is concerned with the quantification of the scale of the performance gap. This paper adds to this body of evidence by drawing retrospectively on a range of grey literature evaluations of low-carbon technologies (including energy-efficiency measures, renewable heat and renewable electricity) in the UK household sector. The focus is on not only the quantification of the performance gap but also the qualitative factors often overlooked, such as installation issues or installer/user behaviour. Recommended policy changes include the development of evaluation standards, the experimentation with pay-for-performance programmes, ensuring that installation standards for low-carbon technologies are being enforced, and taking reasonable steps to ensuring that end users can use any new technology effectively. [ABSTRACT FROM AUTHOR]

In this study, a long-range energy alternative planning (LEAP) model was built to evaluate the relative priority of three kinds of policies expected to be implemented for the energy-intensive manufacturing sectors (EIMS) in China to achieve CO2 mitigation and energy conservation targets. These policies encourage (1) the use of more electricity instead of coal; (2) the continuous improvement of energy efficiency; and (3) a shift to other less energy-demanding sectors. The results indicate that the policy of shifting economic activity from the EIMS to other sectors is most helpful for China to achieve its targets of mitigating CO2 emissions and conserving energy. Encouraging the EIMS to use more electricity can help China to achieve a higher proportion of non-fossil-fuel based energy in its overall primary energy consumption. No single policy will allow China to achieve all the targets, emphasizing the need for an integrated policy design that combines all types of policies. Key policy insights The policy of encouraging a shift to less energy intensive industries should receive the highest priority in aiming to peak China's energy-related CO2 emissions as early as possible, and lower overall CO2 emissions, coal consumption and primary energy consumption in the long run. Encouraging a shift to electricity should go hand-in-hand with greater energy efficiency, otherwise such a policy cannot help China significantly reduce energy-related CO2 emissions. Encouraging the EIMS to use more electricity should receive the highest priority in helping China achieve a higher proportion of non-fossil-fuel based energy in its overall primary energy consumption. [ABSTRACT FROM AUTHOR]

India has demonstrated that it is possible to reduce energy demand and increase the energy efficiency of its buildings, particularly for air-conditioning appliances. Given the rapid and large expected increase in India's building stock over the next 20 or more years, the opportunity exists to make significant increases in overall energy efficiency and reduce energy demand through the application of its Energy Conservation Building Code that influences the design, construction and operation of buildings. However, the responsibility for this code resides with local authorities (urban local bodies) that currently lack sufficient incentive to implement and enforce it. To overcome this impediment, it is argued here that important benefits can be captured by local authorities to implement energy-conservation measures: increased revenues from taxes, improved attractiveness to business and citizens, and the introduction of automation to reduce transaction costs in the building-approval process. Large parts of the country's property (real estate) are yet to be built, providing a valuable opportunity to transition to low-energy and climate-friendly solutions in India's rapidly growing building stock. [ABSTRACT FROM AUTHOR]

Residential electricity consumption in India has increased by a factor more than 50 since 1971. India’s electrified households on average still consume less than one-third of the world’s average for electricity. Rapid electrification, increasing incomes and technology development can result in increased appliance ownership and higher electricity use. A better understanding of this demand can help to develop effective energy-efficiency policies, optimize the addition of generation capacity, and tackle challenges of climate change and environmental pollution. However, research on residential electricity consumption has received limited attention in India until now. A systematic examination of determinants of residential electricity consumption will require an interdisciplinary approach involving the fields of engineering, economics (traditional and behavioural), anthropology, architecture and others. A two-step approach is presented to advance understanding. First, a critical literature review from different disciplines is presented that explores residential electricity consumption in India. Public data sets are also analyzed to gather insights and highlight inconsistencies. Second, an interdisciplinary approach is proposed and developed that can be adopted for research on residential electricity consumption in India. The data needs and systems to facilitate such an approach are provided. [ABSTRACT FROM AUTHOR]

Energy consumption is a central factor taken into consideration as far as management decisions are concerned in any firm and the same goes for the banking industry. More importantly is the extent to which firms consume energy efficiently. In the light of this, this study investigates the energy benchmarking of 50 commercial bank branches in Lagos. With the aid of questionnaires and by observation and consultation with the staff of the selected bank branches, data were collected on the energy use as well as several other variables that influence energy use intensity. An energy use intensity model was estimated using the fixed, random and pooled ordinary least square specifications and the predicted energy use intensity was constructed. Armed with the observed and predicted energy use intensities, an absolute benchmarking was conducted while a relative benchmarking was also conducted with the aid of the Data Envelopment Analysis (DEA) technique. The results of the regression analysis revealed a maximum of 60% of the branches of banks are energy efficient. However, the results of the DEA suggest that only a single branch of the 50 sampled branches was energy efficient while the other banks fell below the energy efficiency frontier with some banks performing relatively poorer than the others. [ABSTRACT FROM AUTHOR]

Energy efficiency is getting more important due to energy cost and environmental effects. Pumping systems are important because they consume almost 20% of the total energy in land power installations. Comparing to the land installations mentioned above, the energy consumed by pumps in marine installations is much greater. In this study, it is shown that the energy consumed by pumping systems onboard ships is almost 50% of the total energy consumption. These pumps work at a constant speed, in other words constant mass flow. However, some of the systems are working under variable load. For example, seawater cooling system load depends on some parameters such as seawater temperature and engine load. Therefore, the consumed energy of this system can be reduced depending on the seawater temperature. A variable speed pump is one of the solutions to save the energy in this system, which will change the pump speed depending on seawater temperature. In this paper, the energy-saving potential of a central cooling water system is analysed. The saved energy and related annual cost of the pump occupied in the system are calculated for different seawater temperatures, and its environmental results are also discussed. [ABSTRACT FROM AUTHOR]

In this study, published information on nonprocess energy use, which includes lighting, heating, cooling, ventilation, humidity control, and particulate control, for industrial buildings has been analyzed and compiled and then represented in power intensity (W/ft2). More than thirty different sources of data related to industrial building energy use (covering about 82 buildings) were identified and analyzed. Energy receives a lot of consideration in analyzing prospective savings in industrial facilities since the industrial sector consumes more than 30% of the total energy in the US. The main objective of this study is to establish representative ranges for nonprocess energy use that can then be used with full process the life cycle for industrial products. The industrial manufacturing buildings were classified into six categories according to nonprocess energy use. The power intensity for each building category was estimated from the available data. Previous analyses of industrial energy use often expressed nonprocess energy as a percentage of total energy but without clear values of actual nonprocess energy. This information is a low value since the actual nonprocess energy is then dominated by the dominator which is unspecified. [ABSTRACT FROM AUTHOR]

Due to autonomous operation and constrained resources, nodes of a wireless sensor network are susceptible to failures. Due to multiple node failures, network topology may change or partition into many disconnected segments causing data/query path breakage. Early detection and recovery of faults is desirable in most scenarios. Also, due to limited battery life of a node, the solution must consume minimum possible energy for prolonged network operation. Hence in this paper, we propose a Fault Detection and Recovery scheme which is an energy efficient fault detection and recovery strategy that achieves minimum data loss by efficiently replacing faulty node on the present route or by finding full or partial alternate paths. Topology is managed by constructing a virtual grid over the entire network which helps in managing dynamically changing network topology easily and makes failure detection and recovery effective. It also helps to create energy efficient path between a source and a sink by finding shortest possible path. Further, nodes’ cooperation is exploited to create certain zones on the data/query path which provides alternate nodes or possible alternate paths if required on some node failures. Thus, scheme achieves fault tolerance and at the same time achieves energy efficiency by always selecting shortest path for data delivery between source and sink. Analytical and simulation study reveals the significant improvement in terms of fault detection and energy conservation over existing similar schemes. Fault Detection and Recovery (FDR) scheme using virtual grid which is an energy efficient fault detection and recovery strategy that achieves minimum data loss by efficiently replacing faulty node on the same route or by finding alternate (full or partial) path. [ABSTRACT FROM PUBLISHER]

As global warming is on the threshold of each country worldwide, Middle East and North African (MENA) region has already adopted energy efficiency (EE) policies on several consuming sectors. The present paper valuates the impact of temperature increase in the residential building sector of Egypt that is the most integrated example of the 7 out of the 20 MENA countries that have started their green efforts upon building environment. Furthermore, as it is based on a literature research upon socio-economic characteristics, existing building stock, existing legal and institutional framework, it elaborates a quantitative evaluation of Egypt's energy-saving potential, outlining basic constraints upon energy conservation, in order for Egypt to be able to handle the high energy needs due to its warm climate. Last but not least, the paper proposes a policy pathway for the implementation of green building codes and concludes with the best available technologies to promote EE in the Egyptian building sector. [ABSTRACT FROM AUTHOR]

The current study revisits the dynamic causality in energy production and real output growth in Nigeria. The imperative of energy production in stimulating output growth is generally well documented and appreciated. Thus, the significance of energy as a driving force for economic growth and development is undisputed. The current study adopts the Autoregressive Distributed Lag (ARDL) bounds test methodology developed by Pesaran et al. (2001) with the modified Granger causality test within the framework of an Unrestricted Vector Autoregressive model. Estimation covers the recent time period between 1971 and 2013. The results show the absence of long-run cointergration relationship in the model. The modified causality test validates the neutral hypothesis for Nigeria. Hence, Nigeria can commit to sustainable energy conservation with emphasis on energy efficiency without hurting the real output growth in the country. [ABSTRACT FROM PUBLISHER]

Recently, Jakarta has implemented a new standard for new building construction to reduce the energy consumption of office buildings. This has to meet the minimum overall thermal transfer value (OTTV) of 35 watt/m2. In tropical countries, the most effective passive design strategy method is the use of shading devices. Dense shading will more effectively reduce energy consumption but will reduce visibility through the opening. Sudare is a traditional Japanese blind made from bamboo.Its original function was to prevent direct solar radiation and introduce natural ventilation. The characteristic Sudare form makes it possible to see through to objects outside the house. The aim of this research is to identify an alternate mode of façade configuration using external horizontal blinds based on the Sudare form to meet the minimum standard of Indonesian National Standard (SNI), with greater efficiency in terms of thermal energy use to minimize energy consumption and maintain visual comfort. Ladybug and Honeybee inside the Grasshopper plugin of Rhinoceros 3D with the Energy plus engine will be used to simulate a standard building as baseline performance, and buildings that use different Sudare dimensions and spacers as shading devices parametrically. Based on this study, the optimum form of Sudare blind, with a diameter of 10.01 mm and 5 mm spacers, has achieved a 5% reduction in OTTV and a 6% reduction in thermal energy use, as compared to the baseline building. It also gives better uniformity of daylight distribution, which improves visual performance and comfort. [ABSTRACT FROM PUBLISHER]

Data envelopment analysis (DEA) is the most frequently used technique among efficiency measurement methods, with more and more models being derived from it. Among its various models, the Dynamic slacks-based measure (SBM) model proposed by Tone and Tsutsui evaluates efficiency in a continuous period and takes into consideration the effect of carry-over activities. This study uses this model to evaluate the efficiency of Asia-Pacific Economic Cooperation (APEC) member economies over 18 consecutive years with findings that show: over the 18-year research period, their average efficiency in 2008 is the best; in terms of geographic areas, the Oceania member economies have the best efficiency; and in terms of the improvement direction of energy savings and carbon reduction, most member economies should set up policies targeting energy consumption savings. [ABSTRACT FROM PUBLISHER]

Machine tool, which is the basis energy consumed device in manufacturing system, its energy consumption model and energy efficiency evaluation are the prerequisites for energy saving in manufacturing. Considering the multi-energy-sources features，analysed the mathematical model of a CNC continuous generating grinding machine tool from the view of energy constitute. The energy sources of a CNC continuous generating grinding machine tool are classified into gear grinding system, grinding wheel dressing system and auxiliary system. Based on the power balance equations of energy flow, the energy flow system of a CNC continuous generating grinding machine tool is established. And then the energy consumption mathematical model of a CNC continuous generating grinding machine tool is set up by combining the power balance equations with the operating features of three kinds of energy sources. The case study shows that the proposed energy consumption model can provide fundamental support for energy consumption forecasting, energy efficiency analysis and energy-saving optimisation during the machine tool operation process. [ABSTRACT FROM PUBLISHER]

Over the last 20 years, economy of Chile grew faster than any other country in South America, thanks to its rigorous economic and political systems and its integration to the global economy. Nonetheless, Chile faces the continuing challenge of finding additional energy supplies to support its economic growth. The country has almost no fossil fuel resources and depends heavily on external sources that accounts for around 60% of its energy needs. However, this may change in the near future, as Chile has started developing its huge potential of sustainable energy sources. This paper examines strategically important energy alternatives for Chile, including energy efficiency (EE) programs, large hydro projects, renewable energy, and nuclear power, focusing on recent developments and remaining challenges. It also gives some recommendations providing alternatives to remove the obstacles. [ABSTRACT FROM PUBLISHER]

India, being one of the fastest-growing economiess in recent times, has witnessed a rise in energy consumption with associated implications on energy availability and energy security. The country recognizes these challenges and has accelerated its efforts with varied degree of success by initiating various programs, policies, and required institutional arrangements to ameliorate these challenges. This paper attempts to review the development of nation’s policy programs to trace the progress so far, in terms of energy efficiency and conservation. Energy being a cross-sectoral issue has been dealt with holistically in this paper, with special reference to the policy instruments that have been instrumental in realizing the energy-saving potential and in integrating renewable energy in building sector. Further, an attempt is made to draw the success/failure with respect to various policies and programs, along with a detailed analysis of various missions under the National Action Plan on Climate Change. [ABSTRACT FROM AUTHOR]

Energy saving is now an important household priority in Dhaka. Energy crisis especially electricity crisis is one of the most important sufferings of the residents in Dhaka. As tackling such immense problem requires initiatives from both government and household ends, this study focuses on appraising the energy saving attitudes of the households in Dhaka to help government in designing and implementing appropriate policy options. Using a sample of 400 households, surveyed in a cross-section of locations in Dhaka, the study reveals that there is an encouraging level of homogeneous knowledge about energy challenges and various dimensions of energy-saving attitudes. Furthermore, the price of the energy-saving appliances is considered as one of the most important impediments in achieving a more comprehensive energy-saving response among the household is quite well match with the socioeconomic characteristics of the majority of the residents in Dhaka. [ABSTRACT FROM PUBLISHER]

One of the methods with the most potential to reduce energy consumption in grain drying is heat recovery from the dryer exhaust air. A parallel plate heat exchanger to recover heat energy from the exhaust air of a recirculating batch grain dryer was examined by theoretical assessments as well as by measurements in a scaled-down research dryer and experimental heat exchanger. In addition to the heat transfer performance, the operability in dusty conditions was investigated. Finally, the optimization of the heat exchanger was introduced by the aid of the calculation models and practical measurement. The heat exchanger performed satisfactorily, providing an average energy saving of approximately 18%. A significant improvement in the performance could be achieved by increasing the air velocity. No severe dust accumulation was observed, and a heat exchanger of this type could provide remarkable energy saving possibilities in grain drying. Further tests are necessary to ensure the operability in long-term use. [ABSTRACT FROM PUBLISHER]

The construction industry is estimated to account for 40% of annual global energy use and 30% of annual greenhouse gas (GHG) emissions. The Intergovernmental Panel on Climate Change (IPCC) has suggested the construction sector as best placed to improve its energy performance in order to help Ireland to meet the European Union (EU) GHG reduction target of 20% by 2020. An action research (AR) approach was used to explore the construction phase energy reduction opportunities on a selected case study in the West of Ireland. The participating contractor’s current onsite energy management practices were benchmarked to inform the implementation of a series of quick-win measures at a cost of €706.04. The resultant savings of €19 853.03 represented 17.5% of the total expenditure on energy usage on site (€113 397) and resulted in an estimated saving of 5.5% of the assumed project profit (€358 800). A set of key performance indicators (KPIs) were calculated for both phases of the project with a 75% reduction in the cost of electricity per floor area from phase 1 to phase 2. The findings suggest that improving site energy use provides scope for the contractor to increase profit margins, improve resource efficiency and reduce environmental impacts. [ABSTRACT FROM PUBLISHER]

The article discusses a research project on developing sustainable design and concepts for museum storage facilities to improve conservation of cultural heritage. The research project aims to develop energy conservation solutions and optimize storage ventilation. Topics discussed include the use of indoor climate simulation model, environmental engineering, and modulating storage temperature. The importance of quality management, sustainability, and influence of building materials while building museum storage facilities is mentioned.

Zero-energy houses, one of the progressive types of energy-efficient homes, theoretically consume no energy for heating, cooling, or other daily activities. The purposes of this research were to identify representative experimental housing projects in South Korea and analyze their major features in terms of energy efficiency and environmental friendliness. This study used case studies consisting of two zero-energy experimental houses and one occupied zero-energy neighborhood. This study found that efforts have been made to build zero-energy homes in Korea. The study also found renewable energy systems such as solar and geothermal systems have been applied in zero-energy houses in Korea. The study discusses future research needs focusing on post-occupancy evaluations that should involve current residents to maintain energy-efficient housing performance. In addition, a holistic strategy to embrace design, development, and maintenance aspects of zero-energy houses should be established to promote this energy-efficient and environmental-friendly housing option for diverse resident groups. [ABSTRACT FROM AUTHOR]

The energy efficiency of US multifamily rental housing is compared with other housing types. A real and growing energy efficiency gap is documented, particularly for lower income households. Findings are based on data from the 2005 and 2009 US Residential Energy Consumption Survey (RECS). Individual energy efficiency features related to HVAC (heating, ventilation and cooling) systems, appliances, and the building envelope are analysed along with weighted and unweighted total energy efficiency indices. Multifamily units occupied by low income renters had 4.1 fewer energy efficiency features in 2005 and 4.7 fewer in 2009 compared with other households. If the number of efficiency features was on par with other housing, the savings could be in the range of US$200–400 per year for most lower-income renters in multifamily buildings. There is an astonishing lack of information on how efficiency retrofits would affect property (real estate) metrics such as cash flow and value. Available evidence suggests that millions of US properties could be good retrofit investment opportunities. Better efficiency would allow renters to increase spending on food, healthcare and other essentials. This is not only an economic issue: it has implications for household health, social equity and environmental problems tied to energy consumption. [ABSTRACT FROM AUTHOR]

Residential home energy assessments, also known as home energy audits, are comprehensive evaluations of a home's energy use conducted by certified home energy raters. Energy assessments help consumers identify areas in their home where significant energy savings can be made. Energy assessments also identify occupant behaviors that contribute to overall energy use. The E-Conservation Consumer Energy Education Program successfully utilized home energy audits to help consumers identify building structure and occupant behaviors that contributed to high energy use in their homes. Examining impacts of the audits revealed that those homeowners who were able to implement suggestions from the energy audits realized home energy savings. Examination also revealed that time, cost, and lack of information served as barriers to making home energy efficient improvements. [ABSTRACT FROM AUTHOR]

In recent years, data processing technologies like MapReduce in cloud computing have been widely used. However, the problem of high energy consumption (EC) is an obstacle for further development of cloud computing. We believe that EC could be reduced not only by hardware reinforcement but also by software improvement, especially, by energy-aware task scheduling. In this paper, the Best resources assignment model (Bram) is proposed. On this basis, a scheduling approach, concerning resource usage of nodes and different kinds of resource intensive tasks running on them, is proposed to avoid resource idleness, and then reduce energy consumption. The experimental results show that the new method could reduce the energy consumption of MapReduce cluster. [ABSTRACT FROM AUTHOR]

In this paper, an experimental study has been performed for mixed (solid+gas) fuelled boiler operating at 7000 kPa pressure and 778·15 K temperature with a nominal capacity of 25 kg s-1 in order to find improvement in the boiler efficiency and to reduce its environmental emissions. In this scope, while the boiler was working under operating conditions, temperature, pressure, velocity, and combustion gas measurements were performed and the measured data were used to establish mass and energy balance. Main efficiency loses were identified as operation of the boiler with high excess air factor (39·78%), leakage air in the rotary air hater and surface thermal losses. Calculations, were performed with the use of measured data, estimated that the boiler and second law efficiency were calculated as 85·3 and 39·6% respectively. When the injected heat value on water is 67 433·65 kW in the boiler, by the reduction of excess air factor is 550 kW and by the prevention of leakage air is 1251·6 kW, including totally saving amount is 1801·7 kW. Financial value of this saving was calculated about 309 465$. [ABSTRACT FROM AUTHOR]

Large areas of our cities are taken by impervious areas, which reduce infiltration and increase peak flows, leading to flash floods and rendering less water for storage and use. At the same time, urban water demand is growing at an unsustainable pace. An innovative system design combining permeable pavements with underground water storage is proposed to reduce runoff peaks, store water, treat pollutants, lower ambient temperatures (heat island effect), and harvest energy from the heated pavement. The proposed system is highly exploratory and aims to answer questions such as what existing technological options could be used, how are the elements of the system integrated, and what are the potential benefits? Through a prototypical case application in an industrial area in Singapore, it was found that the proposed system could significantly reduce runoff and peak flows and slow the recharge of underground water storage. The sizes of urban drains can therefore be reduced significantly, thereby freeing up valuable urban space – a primary sustainability concern in crowded urban cities. We also found that the proposed design solution has not satisfied decision and policy-makers on energy-harvesting and heat-island-effect reduction. We conclude by discussing our lessons learnt from the exploratory study from the technical, economic, and sustainability perspectives. [ABSTRACT FROM AUTHOR]

A lot of policy interest and analysis has been focused on energy saving obligations on energy distributors or suppliers (mainly electricity and gas) coupled with trading of certified energy savings via tradable white certificates. While in the European Union the Energy Services Directive (2006/32/EC) also applies to transport fuels and some of the existing energy saving obligations allow certification of savings from transport projects, as of the end of 2009 no EU Member State has energy saving obligations on transport fuel distributors. The article explores the application of energy saving obligations in road transport, discussing the imposition of energy saving obligations on transport fuel suppliers, the definition of eligible technologies and projects, and considering energy saving obligations as a stand-alone tool or integrated with existing electricity and gas obligations. The article intends to open further discussion and research on the topic. [ABSTRACT FROM AUTHOR]

Green building has gained popularity in urban areas for reducing energy use. This study analyzes factors influencing green building adoption and use through five comparative case studies of urban and transitioning (rapidly developing rural) North Carolina counties. Interviews and policy analyses reveal factors determining green building activity in transitioning counties, including the presence ofactive advocacy and industry organisations, supportive governments and knowledge spillover from nearby university sustainability programmes. Confusion over green building processes, hesitance to alter development practices, low inter-governmental co-ordination and feedback between low green building education and government outreach, can limit green building activity. Our findings point to recommendations for federal, state and local government actions to incentivise green building in transitioning areas. [ABSTRACT FROM PUBLISHER]

Eregli Iron and Steel Works Co. (Erdemir) is the largest integrated steel plant in Turkey. In this study, the potential for improving the specific energy use of slab furnace #3 of this plant was analyzed. An energy input and output model was established in order to determine the lost energy in the process. According to the study, energy efficiency of slab furnace #3 was calculated as 64.26%. Even though it seems to be a reasonable efficiency value for a slab furnace, it was noticed that further energy conservation can still be achieved by increasing the temperature of hot charging to the slab furnace and recovering the flue gas sensible heat remaining after the recuperator. [ABSTRACT FROM AUTHOR]

The energy issue is always an important factor in sustainable housing developments. Over the years, a number of energy-saving techniques have been developed to reduce consumption of primary energy and utilise renewable energy in architectural designs. However, the real situation regarding energy-efficient buildings has improved rather slowly during the recent decades, both in the developing and developed countries. Hammarby Sjostad is one of the largest urban housing developments in Europe but is built to standards twice as strict as those currently being applied for new housing, including energy consumption. Eco-villages are small-scale housing developments, usually in the suburbs, where residents also try to create highly specific ecological environments. There are two basic paradigms to solve the current housing problem: top-down (provider paradigm) or bottom-up (support paradigm). This paper analyses the differences between these, especially from an energy efficiency perspective. Housing development is a gaming process between diverse stakeholders. All the stakeholders try to choose different actions in an attempt to maximise their returns. If the proposals made by the architects and engineers are not consistent with the interests of other stakeholders, they have little chance of being applied in actual projects. This paper describes systematic development strategies for the energy-efficient housing project Jun Lin Zijin, a Chinese residential and commercial project furthering the progress of design and construction. [ABSTRACT FROM AUTHOR]

The effect of energy efficiency measures is generally evaluated for one or only a few houses. While the energy and environmental optimization of a particular building design is crucial, this cannot easily draw generic conclusions for future building designs. A method is presented for considering the effect of building geometry in simplified energy and life cycle assessment studies. Based on architectural and functional considerations, realistic ranges were determined for the parameters describing the geometry of 'technically feasible' buildings and their relationships. These parameters include floor area, the number of storeys, the perimeter-to-floor area ratio, the ratio of the building envelope adjoining neighbouring heated buildings, the window ratio and frame factor, the density of partition walls, and the roof slope. An algorithm is developed for the random generation of a large building sample based on the realistic ranges of these geometric parameters. By analysing the results, it is possible to calculate the expected value, standard deviation and confidence interval of the sample. The application of the method is shown in an example. The cumulative non-renewable energy demand is calculated for the whole life cycle and for different building types. On evalue generalement l'effet des mesures de l'efficacite energetique sur une ou seulement quelques habitations. Alors que l'optimisation energetique et environnementale d'un modele de batiment particulier est essentielle, elle ne permet pas de tirer facilement des conclusions generiques pour les futurs concepts de batiments. Cet article presente une methode qui permet de prendre en consideration l'effet de la geometrie d'un batiment dans des etudes d'evaluation simplifiees de l'energie et du cycle de vie. En s'appuyant sur des considerations architecturales et fonctionnelles, on a defini des plages realistes pour les parametres decrivant la geometrie de batiments « realisables sur le plan technique » et leurs relations. Ces parametres incluent la surface au sol, le nombre de niveaux, le ratio entre le perimetre et la surface au sol, le ratio de l'enveloppe de batiments chauffes se trouvant a proximite, le ratio des fenetres et le facteur de chassis, la densite des cloisons et la pente du toit. Un algorithme a ete calcule pour la generation d'un grand echantillon aleatoire de batiments base sur des plages realistes de ces parametres geometriques. En analysant les resultats, on peut calculer les valeurs escomptees, les ecarts standard et l'intervalle de confiance de l'echantillon. L'application de cette methode est decrite au moyen d'un exemple. La demande cumulee en energie non renouvelable est calculee pour l'ensemble du cycle de vie et pour differents types de batiments. Mots cles: geometrie des batiments, morphologie des batiments, parc bati, efficacite energetique, evaluation du cycle de vie, batiments residentiels, Hongrie [ABSTRACT FROM AUTHOR]

For the purpose of energy conservation, we present in this paper an introduction to the use of support vector (SV) learning machines used as a data mining tool applied to buildings energy consumption data from a measurement campaign. Experiments using a SVM-based software tool for the prediction of the electrical consumption of a residential building is performed. The data included 1 year and 3 months of daily recordings of electrical consumption and climate data such as temperatures and humidities. The learning stage was done for a first part of the data and the predictions were done for the last month. Performances of the model and contributions of significant factors were also derived. The results show good performances for the model. The second experiment consists of model re-estimations on a 1-year daily recording dataset lagged at 1-day time intervals in such a way that we derive temporal series of influencing factors weights along with model performance criteria. Finally, we introduce a perturbation in one of the influencing variables to detect a model change. Comparing contributing weights with and without the perturbation, the sudden contributing weight change could have diagnosed the perturbation. The important point is the ease of the production of many models. This method announces future research work in the exploitation of possibilities of this 'model factory'. [ABSTRACT FROM AUTHOR]

This paper investigates solar control film as an energy saver in the fast growing hotel sector in southern China. It investigates claims made for this low-cost retrofitted material in hotel rooms, calibrating reductions in solar gain in summer. It provides reliable and independent data about the performance and economic viability of solar control film in real hotel environments. The study found that, by limiting solar gain, the film helps limit tourism's impact on global warming and climate change. The paper also foreshadows new technical glazing developments. [ABSTRACT FROM AUTHOR]

This research investigates the impact on energy use of the different ways in which office spaces can be organised and used. It explores typical UK office layouts, utilisation densities and intensities on a good practice-base case shell. This is achieved using the TAS, Lightscape and Excel software packages. For the average occupancy of 50%, the analysis indicates that the variations in combined thermal and lighting loads are 19% and 51% during the UK peak winter and summer respectively. The respective per capita load variations are 80% and 16%. The analysis demonstrates that space planning and utilisation have significant impacts on energy use and are important in assessing energy performance. [ABSTRACT FROM AUTHOR]

Exergy is defined as the maximum amount of work and exergy concept gives an effective way by using the conservation of energy principle. This concept is used to evaluate energy use of societies. In this respect, energy and exergy efficiencies are defined to evaluate sector efficiencies in societies. The main principles are then applied to Turkey's utility, transportation, industrial and residential and commercial sectors. In this study, it seen that even though the utility sector is using the most energy and exergy values, industrial sector has the most energy and exergy efficient which are about 65 and 35% respectively. [ABSTRACT FROM AUTHOR]

Light emitting diodes (LEDs) are emerging as a viable source for the general illumination of the built environment. Recent product development efforts have focused on four areas: increased light output, increased conversion efficiency, minimization of color shifts, and increased color rendering index (CRI) for white LED sources. Although little can be argued against the first three areas of development, using CRI as a spectral design criterion may be misguided. Other measures of color preference or color discrimination may be better suited to optimize LEDs for general illumination. In the future, due to the nature of the LED spectral distributions, virtually any source spectrum may be possible, which begs the question: should product development efforts aim to match reference sources that are not optimal in terms of color preference or discrimination? This paper summarizes current theories about LEDs and color. Color shift is discussed as it relates to temperature, age, input current, and dimming. The methods of making white light with LEDs are described and contrasted in terms of chromaticity coordinates, correlated color temperature (CCT), and CRI. The colorimetric potential of LEDs is discussed in consideration of numerous measures of colorimetric performance. [ABSTRACT FROM AUTHOR]

This article deals with the energy performance of eight new and existing museum buildings located around Europe. Various energy efficiency and microclimate improvement measures have been adopted to reduce the energy consumption of the buildings and improve the comfort conditions. The investigation was implemented in two principal phases. During the first phase, energy simulation studies were performed in all buildings to evaluate the efficiency of the proposed measures and the various design possibilities. The energy consumption for heating, cooling, lighting and other electrical devices was calculated with and without the application of the proposed techniques and the corresponding energy conservation was estimated. Therefore, the proper measures from the energy point of view were adopted. During the second phase, measurements of the energy consumption were performed in the buildings after the finalization of the construction and the implementation of the proposed measures. The energy conservation was again calculated to evaluate the energy efficiency of the final construction. In addition to the energy aspect, the environmental impact of the final construction of the museums was investigated by calculating the reduction of the CO2 emissions due to the applied energy conservation techniques. Finally, the economic efficiency was examined by assessing the payback period of the adopted measures.The results of the present work show that the adaptation of energy conservation techniques in museums buildings can reduce significantly the energy consumption by respecting at the same time the requirements of the exhibition spaces and the comfort conditions of the visitors. [ABSTRACT FROM AUTHOR]

For conventional energy technologies, energy and exergy analyses have been performed and have yielded useful results. Besides this, for advanced energy technologies, the use of energy and exergy analyses can be expected to provide meaningful insights into performance that will assist in achieving optimal designs. In this regard, this study describes the modeling and analysis of sectoral energy and exergy utilization. The sectors considered are subgrouped into four main sectors, namely, utility, industrial, commercial-residential and transportation. The modeling presented here is expected to assist in the simulation and optimization activities and also in the planned studies towards increasing energy efficiencies in the sectors studied. [ABSTRACT FROM AUTHOR]

Continued growth and the privatisation of Brazil’s electricity system, which is largely based upon hydropower, is projected to lead to big expansion mainly of natural gas but also coal power stations with a resulting huge growth in greenhouse gases (GHG) emissions unless steps are taken to avoid this. The Brazilian National Program of Power Conservation and Efficient Use of Electrical Energy in terms of avoided GHG emissions (PROCEL), originally created in 1985, is a multi-stakeholder program coordinated by Eletrobra´s aimed to reduce the waste of electrical power on both supply and demand side. Initially crippled by lack of funds, a new finance structure introduced in 1994 has greatly increased PROCEL’s impact. Here we develop scenarios that suggest that continued expansion of PROCEL’s programme, including resources that might be drawn through clean development mechanism (CDM) projects, to meet projected PROCEL targets over the next two decades could avoid approximately one-third of the GHG emissions from the Brazilian power sector. This contribution demonstrates the significant global environmental benefits of PROCEL in addition to national benefits of this innovative programme. [Copyright &y& Elsevier]