兰州地区住宅建筑供暖能耗影响因素分析

为研究影响兰州地区住宅建筑供暖能耗的因素,在围护结构参数完全符合国家现行寒冷地区住宅建筑节能要求的前提下,以兰州市2栋住宅建筑为基准模型,运用De ST-h软件对供暖季的热负荷进行逐时模拟计算,分析窗墙比、体型系数、朝向三大因素对总供暖热负荷的影响,得到了兰州地区住宅建筑南偏西30°朝向与南偏东30°朝向、正南方向相比,总热负荷最小,但最大热负荷最大的结论,为南偏西建筑进行供热调节实现节能提供依据。南向墙面内凹的住宅建筑不宜通过面积热指标法来估算热负荷。     

Benchmarking the energy efficiency of commercial buildings

Benchmarking energy-efficiency is an important tool to promote the efficient use of energy in commercial buildings. Benchmarking models are mostly constructed in a simple benchmark table (percentile table) of energy use, which is normalized with floor area and temperature. This paper describes a benchmarking process for energy efficiency by means of multiple regression analysis, where the relationship between energy-use intensities (EUIs) and the explanatory factors (e.g., operating hours) is developed. Using the resulting regression model, these EUIs are then normalized by removing the effect of deviance in the significant explanatory factors. The empirical cumulative distribution of the normalized EUI gives a benchmark table (or percentile table of EUI) for benchmarking an observed EUI. The advantage of this approach is that the benchmark table represents a normalized distribution of EUI, taking into account all the significant explanatory factors that affect energy consumption. An application to supermarkets is presented to illustrate the development and the use of the benchmarking method.     

重庆市酒店类建筑能耗调查及节能潜力分析

在对重庆市5家典型三星级以上酒店年用电量及空调系统运行调研的基础上,分析重庆市酒店类建筑的能耗特点,探讨空调系统及管理方面各分项节能潜力,为解决重庆市酒店类建筑能耗问题提供一些基础性数据。     

Technology diffusion and energy intensity in US commercial buildings

This paper analyzes the 1992 and 2003 US Commercial Buildings Energy Consumption Survey microdata files to show the extent to which certain heating, cooling, lighting, and window technologies are entering use, and the resulting impacts on the intensity of energy use. Excepting the case of fluorescent lights, no technology dominates the entire market but instead each conquers a specific niche. Most of the buildings in which these technologies are installed do not have lower-than-average energy intensity, measured as annual energy use per square meter of floor space. The exceptional technology that does measurably correlate with reduced energy intensity is daylighting. These results suggest that technologies are adopted to serve comfort or quality objectives rather than to save energy, or that buildings’ users confound the designers’ intentions. Decision makers thus should improve operating and maintenance practices, invest in building commissioning, and rely more heavily on passive design features to save energy.     

The world distribution of commercial energy consumption

Inequality in the world distribution of income has been widely studied. A related problem is the worldwide maldistribution of per capita energy consumption. This article examines trends in the international distribution of energy use over the period 1950–1975. Lorenz curves are used to show that during this 25-year period inequalities in energy consumption have decreased slowly. Most of this redistribution has however occurred among countries in the top 30% of energy consumers. Of the remaining countries only China has significantly increased its per capita consumption. If China is excluded 60% of the world's population accounts for only 10% of total world consumption. This imbalance has remained unaltered since 1950.     

电动汽车的能耗效率分析及提高能耗经济性的研究

通过对比电动汽车和内燃机汽油车的热效率及能耗,得出电动汽车的热效率及能耗明显优于内燃机汽油车的结论,并推断出降低电动汽车的运行能耗、提高其经济性是推动电动汽车产业化的关键因素之一。从整车动力系统、电池以及充电设备等几个方面分析了提高电动汽车能耗经济的途径,指出了今后需要重点研究的关键性问题。     

Estimation of energy intensity by end-use for commercial buildings

We describe the results of a study to estimate the energy intensities of major end-uses in commercial buildings in the PG&E service area. These energy intensities are central to commercial sector electricity and natural gas consumption forecasting models that utilize an end-use approach. The use of more accurate energy intensities will result in improved estimates of new power generation needs. To our knowledge, this is one of only three studies using the conditional demand approach for the commercial sector. This technique is less costly than end-use metering a large number of commercial buildings to arrive at energy intensity estimates. We obtained these energy intensity estimates for offices, food stores, restaurants, retail buildings, hotels and motels, hospitals, schools, warehouses, and miscellaneous buildings. We applied the conditional demand technique to monthly energy use, building characteristics, and weather data to produce annual estimates of natural gas and electricity use per square foot of floor space. The consumption estimates are for the following seven end-uses: space heating, cooling, lighting, water heating, cooking, refrigeration, and miscellaneous use.We have compared the results of our study to those of two other conditional demand studies and to other studies where data are available. Presently, there are few metered data available for comparison with our estimates. For most business types and end-uses, the energy intensity estimates appear reasonable. For example, for lighting, the mean energy intensity for each business type is within 20% of all the individual values from all comparable studies. Additionally, for each enduse, the highest energy intensity values occur for those business types that would be expected to show greatest utilization.However, for some end-uses in some business types, there are large discrepancies in energy intensity estimates obtained from various studies. For example, for restaurants, the energy intensity estimates for electric water heating and cooking each vary by more than a factor of seven from minimum to maximum. Additional research is needed to determine if such large variations in estimated energy intensities are real or if they are due to such factors as differences in business types (e.g. liquor stores may be included in retail or food stores), different distributions within a business type (e.g. different ratios of refrigerated to non-refrigerated warehouses), and different floor area definitions.     

Modelling of electric energy consumption in the AC electric arc furnace

In this paper, the variation of electric energy consumption in the AC electric arc furnace (EAF) with various production parameters is studied using a developed computer program. The energy equation is modelled using the first law of thermodynamics. The effects of temperature of liquid steel, stack gas, scrap pre‐heated and cooling water and duration at which the EAF cover is open on electric energy consumption are investigated. The calculated electric energy values are compared with the actual electric energy used in the EAF and values received from literature. They are in a good agreement. Copyright © 2002 John Wiley & Sons, Ltd.     

住宅区电气节能设计的几个途径

本文从变压器选择、配电系统和绿色照明等三个方面讨论了住宅小区节能设计的方法及实现的途径。     

Forecasting electric energy consumption using neural networks

An artificial neural network model is developed to relate the electric energy consumption in the Eastern Province of Saudi Arabia to the weather data (temperature and humidity), global solar radiation and population. A two layered feedforward neural network is used for the modelling. The inputs to the neural network are the independent variables and the output is the electric energy consumption. Seven years' of data are used for model building and validation. Model adequacy is established by a visual inspection technique and the chi-square test. Model validation, which reflects the suitability of the model for future predictions is performed by comparing the predictions of the model with future data that was not used for model building. Comparison with a regression model shows that the neural network model performs better for predictions.     

Chillers energy consumption, energy savings and emission analysis in an institutional buildings

Chillers consume more than 40% of the total energy used in the commercial and industrial buildings for space conditioning. In this paper, energy consumption by chillers and chilled water pumps, condenser pumps and fan motors has been estimated using data collected by a walkthrough energy audit for the 16 faculties of the University of Malaya. It has been estimated that chillers and motors and pumps used in chillers consume 10,737 MWh (i.e. 51% of total energy consumption) of electric energy for different percentage of loadings. As chillers are major energy users, variable speed drives are applied in chillers to reduce their energy consumption. It has been estimated that about 8368 MWh annual energy can be saved by using efficient chillers at different loadings. It has also been found that about 23,532 MWh annual energy can be saved for chilled water supply pumps, condenser pumps and cooling tower fan motors by matching required speeds using variable speed drives for 60% of speed reduction. About 1,274,692 kg of CO₂ emission could be avoided for using energy efficient chillers at 50% load. It has been also found that about 2,426,769 kg CO₂ emission can be reduced by using variable speed drives for 60% speed reductions. Payback periods found to be only few months for using variable speed drives in chilled water pumps, condensers and fan motors.     

广州地区机关办公建筑能耗调查与节能潜力分析

对广州地区5栋机关办公建筑进行了能耗调查,得到了该类建筑能耗的基本状况,并对其做了节能潜力分析。     

An energy systems engineering approach to the optimal design of energy systems in commercial buildings

Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions.     

Effect of building regulation on energy consumption in residential buildings in Korea

According to the International Energy Agency (IEA), the energy demand for the building sector constituted about 25.3% of the final energy use in South Korea. The energy demand for residential buildings counts for 50.3% of the building sector and has also increased by 2.9 percent every year. The Korean government has shifted focus and is now promoting energy efficiency within the building sector and has set long-term energy conservation goals.Despite these efforts to minimize building energy, the Korean government has changed the building regulation to allow remodeling of the balcony space as a living space. Remodeling the balcony space to become an indoor space means that a buffer space for the outdoor environment is lost, causing thermal discomfort and discomfort glare and moreover, increasing the heating and cooling energy demand in residential buildings. Also, it results in an increase in building energy demand in South Korea.In this study, the effect of the alteration of balcony space on the indoor thermal environment and the heating and cooling energy demand of residential buildings in Korea were investigated by field measurement and simulation. From the measurement results, the indoor temperature of the condition without a balcony was 0.8 °C lower than that with a balcony. The heating and cooling load of the unit without the balcony space was 39% and 22% higher, respectively, than that of the unit with the balcony space. This increase results in considerable energy loss in the national scale and the ratio will be 0.3% of the final energy use in Korea. Also, it represents about 1.3% of the final energy use within the building sector of Korea.     

Identification of the building parameters that influence heating and cooling energy loads for apartment buildings in hot-humid climates

Identifying the building parameters that significantly impact energy performance is an important step for enabling the reduction of the heating and cooling energy loads of apartment buildings in the design stage. Implementing passive design techniques for these buildings is not a simple task in most dense cities; their energy performance usually depends on uncertainties in the local climate and many building parameters, such as window size, zone height, and features of materials. For this paper, a sensitivity analysis was performed to determine the most significant parameters for buildings in hot-humid climates by considering the design of an existing apartment building in Izmir, Turkey. The Monte Carlo method is selected for sensitivity and uncertainty analyses with the Latin hypercube sampling (LHC) technique. The results show that the sensitivity of parameters in apartment buildings varies based on the purpose of the energy loads and locations in the building, such as the ground, intermediate, and top floors. In addition, the total window area, the heat transfer coefficient (U) and the solar heat gain coefficient (SHGC) of the glazing based on the orientation have the most considerable influence on the energy performance of apartment buildings in hot-humid climates.     

Assessing energy efficiency and energy conservation potential among commercial buildings: A statistical approach

Energy conservation in the commercial sector is impeded by the lack of simple yet reliable measures of building energy efficiency. A simple Energy Utilization Index is preferable, but it lacks reliability if it remains unadjusted for significant sources of variation. Linear regression analysis represents a straightforward method for introducing necessary sophistication, but care must be exercised in model specification and sample selection. A model incorporating climate, occupancy patterns, HVAC design, and building type explains 42% of the EUI variance in a sample of Texas school and university buildings.     

重庆市酒店类建筑用能现状与节能潜力分析

在对重庆市公共建筑运行能耗及中央空调系统管理现状调查分析的基础上,并与国内外同类建筑相比较,针对酒店类建筑的能耗特点对影响建筑终端用能系统的能源消费量的因素进行探讨,分析了既有酒店类建筑的节能潜力值,提出了对既有高能耗酒店进行节能技术改造和加强节能管理的主要途径。     

A simple forecasting model for industrial electric energy consumption

A single‐equation model is developed and employed for forecasting industrial electric energy consumption in the Saudi Consolidated Electric Company in the Eastern Province (SCECO‐East) of Saudi Arabia. SCECO‐East's industrial loads are composed mainly of oil‐related and petrochemical industries. Even though industrial loads are generally characterized by their steadiness, the harsh weather conditions of the Eastern Province cause great variations in the industrial electric energy consumption at SCECO‐East. The developed model reflects these variations. MATLAB is used to solve the model. Copyright © 2000 John Wiley & Sons, Ltd.