Comparative assessment of energy requirements for different types of residential buildings in India

This paper presents a comparison of the energy required for major building materials at the time of construction of single and double storey residential buildings with load bearing walls, and four storey residential buildings with reinforced concrete construction in India. For the total floor area of 50–200 sq. m, total energy consumption per unit of floor area decreases, from 5 to 4.1 GJ for single storey, from 4.2 to 3.7 for double storey, and from 4.3 to 3.1 GJ for four storey buildings.     

Predictions of the heating and cooling energy requirements in buildings using the degree hours method

Methods for the prediction of seasonal energy requirements for heating or cooling buildings are briefly discussed, and a new method, the degree hours method, is described. This method requires the simulation of the pattern of internal temperature variations in a passive building over a season in response to exposure to the weather conditions. The seasonal heating or cooling energy requirement can then be calculated in relation to any chosen base temperature. Different base temperatures can be chosen for summer cooling and for winter heating, to allow for comfort requirements and casual heat gains. Predictions using this method are compared with results from an alternative published method, for an example building.     

A comparison of thermal requirements of buildings

In the U.S.A., thermal requirements for buildings have the form of resistance, R for U values; in European countries, the weight or mass of the building shell is included as part of the thermal requirement for a building. In this study, these European thermal requirements, which vary substantially, are numerically tested and compared. The comparison is the ratio of heat transmitted during a day by a wall which incorporates the thermal requirements to a wall which has no mass and only thermal resistance. The comparison shows a wide discrepancy in the thermal response of the requirements for different countries. For the purpose of comparison, the pysical properties of the thermal requirements are normalized to groups which are part of the solution to the differential equation of heat transfer. Also compared are Givoni's recommended requirements which, in relation to other requirements, show good consistency.     

浅论建筑节能

主要阐述了我国目前建筑节能的情况,并指出近期的工作目标,提出了建筑节能的有效技术措施,从而在保证和提高建筑舒适性的前提下,不断提高能源利用效率。     

Analysis of annual heating and cooling energy requirements for office buildings in different climates in Turkey

A great amount of world energy demand is connected to the built environment. Electricity use in the commercial buildings, accounts for about one-third of the total energy consumption in Turkey and fully air-conditioned office buildings are important commercial electricity end-users since the mid-1990s. In the presented paper, the interactions between different conditions, control strategies and heating/cooling loads in office buildings in the four major climatic zones in Turkey – hot summer and cold winter, mild, hot summer and warm winter, hot and humid summer and warm winter – through building energy simulation program has been evaluated. The simulation results are compared with the values obtained from site measurements done in an office building located in Istanbul. The site-recorded data and simulation results are compared and analyzed. This verified model was used as a means to examine some energy conservation opportunities on annual cooling, heating and total building load at four major cities which were selected as a representative of the four climatic regions in Turkey. The effect of the parameters like the climatic conditions (location), insulation and thermal mass, aspect ratio, color of external surfaces, shading, window systems including window area and glazing system, ventilation rates and different outdoor air control strategies on annual building energy requirements is examined and the results are presented for each city.     

The anatomy of investing in energy efficient buildings

A building investment is a real decision because the allocated resources are typically irrevocable for long times. Investment appraisal is a logic method to process elapsing time, uncertain benefits and costs, and irrevocability related to decisions. Most analysts stop halfway the appraisal process when they carefully assess net present values and their sensitivity to uncertain future events. But sidelining irrevocability and the dynamic sequential analysis of future events and actions cause wrong decisions when the energy performance endowment of a new building is decided. Irrevocability and preclusion are explained, and their impact illustrated with a case study. Adopting realistic assumptions about the uncertain future and applying the proper methodology reveal as financially best choice the immediate investment in passive attributes and items. Irrevocability is of high relevance for building efficiency investments and for the implementation of the EU-2010 buildings directive.     

A nomograph for estimating annual cooling and heating energy requirements in buildings dominated by internal loads

This paper describes a nomograph that can be used as a design tool for estimating annual cooling and heating coil loads in interior zones of office buildings. Based on simplified relationships between the heat load on an air-conditioning system, internal heat generation and outdoor air intake rate, the equations for normalized anuual cooling and heating coil loads in interior zones of office buildings are derived as a function of outdoor air enthalpy, two variables related to the intensity of internal cooling load, and the minimum and maximum outdoor air intake rates. Normalization of heat load on an ari-conditioning system made it possible to construct a design nomograph which can be used to calculate the energy-saving effects of an economizer cycle (passive cooling with ventilation air) and an exhaust air heat recovery unit on annual cooling and heating coil loads at the schematic design stage.Example calculations using the nomographs for three locations in Japan show that the energy-sacing effects of economizer cycle and exhaust air heat recovery units are heavily dependent on the profiles of regional weather conditions. A validation study showed that annual cooling and heating coil loads estimated from the nomographs were in good agreement with those from a detailed computer-based calculation.     

Educational buildings : a list of occupants' requirements

CIB working commission W45, under its coordinator Gérard Blachère, of France, considers the design of buildings in terms of the requirements of the people who have to occupy them. In our May/June issue last year we published the commission's up-dated list of human requirements for housing. Now we present its requirements for those using educational buildings.     

Predicting building energy requirements

This paper is concerned with methods of predicting the thermal performance and energy consumption of buildings. The advantages and drawbacks in practical office situations of both approximate methods and the more precise computer methods are discussed. The widespread use of the computer for these calculations will be necessary for implementation of a National Energy Conservation Standard for building design. The new ASHRAE Standard 90–75 essentially requires such computer methods.A case study carried out for the State of California in an effort to determine the practicality of energy budgets is discussed.The outputs of four proprietary energy programs for the same two buildings are compared and found to be remarkably different. The need for an ASHRAE-endorsed public domain computer program is discussed.     

From net energy to zero energy buildings: Defining life cycle zero energy buildings (LC-ZEB)

There are various definitions of ‘zero energy’ and ‘net-zero’ energy building. In most cases, the definitions refer only to the energy that is used in the operation of the building, ignoring the aspects of energy use related to the construction and delivery of the building and its components. On the other hand the concept of ‘net energy’ as used in the field of ecological economics, which does take into account the energy used during the production process of a commodity, is widely applied in fields such as renewable energy assessment. In this paper the concept of ‘net energy’ is introduced and applied within the built environment, based on a methodology accounting for the embodied energy of building components together with energy use in operation. A definition of life cycle zero energy buildings (LC-ZEB) is proposed, as well as the use of the net energy ratio (NER) as a factor to aid in building design with a life cycle perspective.     

古建木雕刻的几点要求

雕刻是建筑装饰的重要手段。古建中的木雕刻由于木材的特点与其它材料有所不同，因此需要注意它与其它雕刻不同的一些特点。古建木雕刻的基本要求，一是图样优美，二是空间布局均匀，三是雕刻部位牵连牢固。     

Modeling energy efficiency of bioclimatic buildings

The application of bioclimatic principles is a critical factor in reducing energy consumption and CO₂ emissions of the building sector. This paper develops a regression model of energy efficiency as a function of environmental conditions, building characteristics and passive solar technologies. A sample of 77 bioclimatic buildings (including 45 houses) was collected, covering Greece, other Mediterranean areas and the rest of Europe. Average energy efficiency varied from 19.6 to 100% with an average of about 68%. Environmental conditions included latitude, altitude, ambient temperature, degree days and sun hours; building characteristics consisted in building area and volume. Passive solar technologies included (among others) solar water heaters, shading, natural ventilation, greenhouses and thermal storage walls. Degree days and a dummy variable indicating location in the Mediterranean area were the strongest predictors of energy efficiency while taller and leaner buildings tended to be more energy efficient. Surprisingly, many passive technologies did not appear to make a difference on energy efficiency while thermal storage walls in fact seemed to decrease energy efficiency. The model developed may be of use to architects, engineers and policy makers. Suggestions for further research include obtaining more building information, investigating the effect of passive solar technologies and gathering information on the usage of building.     

集中太阳能系统在居住建筑中的应用

分析比较了集中集热储热与分户储热两种集中式太阳能系统的优劣势,着重阐述了集中集热分户储热系统的选型及储热水罐的设置方法,在保证太阳能系统安全可靠的前提下,充分利用太阳能资源。     

浅谈建筑节能设计

以降低建筑的空调负荷,实现建筑节能为出发点,结合地区气候特征,从建筑物围护结构入手,阐述了通过改善建筑围护结构的保温隔热性能降低冷热量损失的具体措施,并介绍了环境控制技术、夜间通风等节能途径,以实现建筑节能目标。     

Using buildings to harvest wind energy

Research and development by Altechnica into the applied use of wind energy suggests the novel and innovative solution of employing buildings as primary wind collectors. Buildings can be designed with the means of extracting wind energy advantageously. The roof design of a building can direct and accelerate the wind flow to turbines along the ridge. Dr Derek Taylor of Altechnica introduces the idea of a wind energy system for (new and existing) buildings that can augment solar power, work for a range of building typologies and settings, generate electricity for the building and contribute into the larger electric grid.     

对节能建筑的探讨

一、正确认识节能建筑 随着城市建筑突飞猛进地发展,建筑市场十分活跃,特别是住宅建设大幅度地增长,节约能源、保护耕地、保护环境、改善人民的居住条件,已成为现阶段紧迫重要的任务。 由于人民的生活水平不断提高,住宅消费已是主要方向。现阶段由实物分房转变到货币分房,消费者的经济低收入,购买力差和现阶段的房价发生了矛盾。在供大于求的市场竞争中,必须改变经营战略,以经济实用住宅面向消费者。 降低住宅成本,提高工程质量,改善住宅条件,是保证群众的利益;保证质量,加强管理,降低热耗成本是保证企业的长远利益;保护环…     

The use of tuff stone cladding in buildings for energy conservation

Heating the houses in cold climates requires large quantities of heat energy to be spent. The building sector consumes more energy in the form of heat than other sectors. Therefore, considerable energy savings can be obtained by using natural rocks with low thermal conductivity in insulating the buildings. In this study, the amount of energy conserved by using porous tuff stone in external walls of buildings is calculated. It was shown that considerable energy savings can be achieved by using tuff stone for facing buildings in cold climate zones such as Isparta region. The cost of installing tuff stone panels for facing buildings will be paid back in four years by savings in heat energy.     

建筑蓄能在寒地农村住宅中的应用研究

在寒地农村住宅中．利用建筑材料本身的构造组合蓄能,来减少常规能源的消耗,是重要的节能方法．本文探讨了在寒地农村住宅中适宜的建筑蓄能方法,这种方法是低技术低成本的,在寒地农村住宅中大有应用前景。