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Abstract: In order to meet new tighter building energy requirements introduced in Denmark in 2006 and prepare the way for future buildings with even lower energy consumption, single-family houses were built with the purpose to demonstrate that it is possible to build typical single-family houses with an energy consumption that meets the demands without problems concerning building technology or economy. The paper gives a brief presentation of the houses and the applied energy-saving measures. The paper also presents results from measurements of the overall energy use, indoor climate and air tightness. Furthermore, results from detailed calculations of the utilization of electricity-related heat gains are presented. Looking at the energy consumption in relation to the new energy requirements, the paper concludes that the single houses can relatively easily keep the future energy demands. The energy consumption of the houses is on a level corresponding to a classification as “low-energy house class 2” or an energy consumption of 75% of the required maximum energy consumption. With minor modifications, some houses could be classified as “low-energy building class 1” corresponding to an energy consumption of only 50% of the required and almost the level of typical passive houses. [Copyright &y& Elsevier]

Abstract: This paper describes a novel method for detecting abnormal energy consumption in buildings based on daily readings of energy consumption and peak energy consumption. The method uses outlier detection to determine if the energy consumption for a particular day is significantly different than previous energy consumption. For buildings with abnormal energy consumption, the amount of variation from normal is determined using robust estimates of the mean and standard deviation. This new data analysis method will reduce operating costs by detecting problems that previously would have gone unnoticed. Also, operators should save time by not having to manually detect faults or diagnose false alarms. The new data analysis method has successfully detected high-energy consumption in many buildings. This paper presents field test results for buildings that had the following problems: (1) chiller failure and a poor control strategy, (2) poor design of ventilating and air-conditioning equipment, and (3) improper operation of equipment following a change in the electrical panel. [Copyright &y& Elsevier]

Abstract: Energy analysis of complex buildings is usually carried out by process analysis. The results are indices of the direct consumption by final energy carriers. This analysis, however, is not complete because the final energy carriers are generated in a system of interconnected production and transport processes, where energy is also used. The sum of the direct energy use, the energy used in intermediate stages and in transport is termed cumulative energy consumption. The analysis of cumulative energy consumption may concern either one single final energy carrier (e.g. electricity) or the global primary energy consumption. The theory of cumulative energy consumption belongs to the class of system methods. This paper applies one system method, input–output analysis, to compare different systems of supplying energy to buildings. The linear mathematical model of annual energy balance of a complex case-study building has been formulated. The paper describes the application of such a linear mathematical model for calculating the coefficients of cumulative energy consumption in buildings as well as for evaluating the effects of energy rationalisation systems and strategies. [Copyright &y& Elsevier]

• The new power supply structure resulting from the new policy has been considered. • The new models project the inefficient points onto a more realistic efficient frontier. • The new models have the power to allocate the shared resources. • Results show that the power production stage is allocated less shared resources. • The power sale stage's efficiency is lower than the one of power production stage. To relieve the problems of energy shortage and environmental pollution, many countries have implemented a variety of policies to improve the energy efficiency of the power industry. To understand the impacts of such policies on energy efficiency, this paper constructs novel network data envelopment analysis models to recognize the policy-induced structural changes in the power system. Compared with previous studies, the new models project the inefficient points onto a more realistic efficient production frontier, considering how the distribution proportion of shared resources will change when the power system, modeled as a power generation stage and a power sale stage, is led by the latter stage. Our empirical study on China's power system shows that the province of Guangdong and the eastern region of China perform best, and all power production stages perform better than the corresponding power sale stages. The development of the two power subsystems in the four regions is unbalanced. More than half of the power supply systems choose to allocate more proportion of the shared resources to the sale stage rather than use a more balanced distribution between the two stages. [ABSTRACT FROM AUTHOR]

Abstract: This paper details the physical effects of a government sponsored, residential energy efficiency upgrade program in New Zealand, with data gathered from 100 houses located in Dunedin. House energy use and thermal indoor environment were monitored over a 2-year period. Houses were found to be 0.4°C warmer (annual average increase) after the upgrade with a 0.6°C increase recorded over the winter months, after being corrected for energy consumption and weather conditions. A small, but statistically insignificant, reduction in energy consumption was also found. In absolute terms, indoor temperatures were found to be very low and did not come close to WHO recommendations. The data showed occupants could be exposed to indoor temperatures below 12°C for nearly half of the 24h day during the three winter months. The findings were quite surprising as the upgrade program had the goal of making houses warmer and healthier by reducing heat loss through improved thermal insulation. Householders, however, provided very little heating to living areas and even less to bedrooms thus contributing to the less than desirable indoor thermal environment. [Copyright &y& Elsevier]

Abstract: The ability to predict how changes in patterns of usage in different types of dwelling can affect energy consumption is important if efforts to reduce demand and carbon emissions are to be effective. This paper describes an approach using a questionnaire survey, supported by annual gas and electricity meter data and floor-area estimates derived from a GIS. Clusters of higher and lower energy consumers were discovered and these were related to indicators of energy consumption. Simple and multiple regression were used to determine the strength of the relationships and identify the most statistically-significant indicators of differences in gas and electricity consumption. Although significant effects of the built-form type were not observable in the data available, the effects of related measurable and countable aspects of form, such as floor-area and numbers of rooms, were seen. Significant relationships were found with the number of bedrooms and regular home working, which may reflect changes in UK households that are expected to drive future energy-consumption. Implications for zonal domestic energy-models are noted. [Copyright &y& Elsevier]

Abstract: A two-storey rammed earth building was built on the Thurgoona Campus of Charles Sturt University in Albury-Wodonga, Australia, in 1999. The building is novel both in the use of materials and equipment for heating and cooling. The climate at Wodonga can be characterised as hot and dry, so the challenge of providing comfortable working conditions with minimal energy consumption is considerable. This paper describes an evaluation of the building in terms of measured thermal comfort and energy use. Measurements, confirmed by a staff questionnaire, found the building was too hot in summer and too cold in winter. Comparison with another office building in the same location found that the rammed earth building used more energy for heating. The thermal performance of three offices in the rammed earth building was investigated further using simulation to predict office temperatures. Comparisons were made with measurements made over typical weeks in summer and winter. The validated model has been used to investigate key building parameters and strategies to improve the thermal comfort and reduce energy consumption in the building. Simulations showed that improvements could be made by design and control strategy changes. [Copyright &y& Elsevier]

Abstract: This paper addresses the issue of energy performance of data centers by closely examining energy use of two data centers in commercial office buildings. The primary objective of the study is to examine an empirical energy use pattern of data centers under tropical climatic conditions, and give guidance for data centers’ design, operation and maintenance and retrofitting to achieve better energy performance. Actual energy use characteristics, design criteria, and energy and cost saving potentials were analyzed and compared between two data centers. Methodology of energy performance evaluation of data centers was discussed. The study concludes that data centers were high energy consuming areas in commercial office buildings—energy consumptions of approximately 3000kWh/(m2 year) and 2000kWh/(m2 year), respectively, were observed in the case studies. Power demands were often grossly over-provided in these facilities. This leaded to substantial increase in capital and running cost, which can be wasteful. Disparity in energy performance between case studies demonstrated the need for design guidelines and practical benchmarking. In one case study, approximately 56% (1.2GWh/year) of energy consumption could be conserved through efficient designs of base infrastructure and energy consuming systems, as compared to better practice. The predicted cost saving is more than US$ 80,000 per year. [Copyright &y& Elsevier]

Abstract: Combined cooling, heating and power (CCHP) is getting more attention for its energy saving. However, until now it is not clear yet that how to evaluate the energy utilization of CCHP scientifically and if energy saving is intrinsic to CCHP systems. One of the reasons for this lies in the inappropriate selection of reference situations that making the comparison between the gas cogeneration and the separate production fueled by coal. Another is that the ideal efficiencies of CCHP units are often cited and the differences of various practical performances are often ignored in the comparison. In this paper, an appropriate reference situation is suggested and the practical statistical performances of various units are introduced. Then, a static calculation methodology for evaluating the primary energy consumption for CCHP and separate productions is presented. Fuel energy saving ratio (FESR) definition and the boundary conditions that have to be met by CCHP systems for being energy saving to separate productions are given. Moreover, the energy saving performances of various types and sizes systems in heating and cooling modes are analyzed. Energy saving is not intrinsic but conditional to CCHP systems. The systems with the larger electric power have the higher energy saving potential. [Copyright &y& Elsevier]

Abstract: In this paper, we proposed a new process for fabricating electrochemical double layer capacitors employing active carbon and multi-walled carbon nanotubes to adsorb and from NaCl solution. Due to their unique mesoporosity, active carbons have high ability to desalt NaCl solution. But they have many defects such as high electrical resistance, high-energy consumption and low intensity. Since carbon nanotube is a new material which has high intensity and low resistance, we can composite the merits of active carbon and carbon nanotube and develop carbon nanotube/active carbon materials combination electrode. It was tested that when carbon nanotube content in carbon materials is 10%, the characteristics of combination electrode is the best for us to desalt brackish water because of their high desalination characterization and low energy consumption. Though there are a few technical problems to be solved, our results show a promising technique for desalting salt water. [Copyright &y& Elsevier]