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Abstract: In the last years many studies concerning the evaluation of the thermal conductance of building elements via measurements have been carried out; this value has to be ensued from the analysis of recorded temperature and heat flux profiles. The determination of this property in situ would allow a more accurate a more accurate evaluation of the real heating energy demand of a building. Papers discussing different data analysis methods are present in literature and measurements on test components under real conditions and evaluations on different theoretical aspects by means of numerical simulations have been already developed. This paper aims at widening the existent literature of the in situ evaluation of the thermal conductance, through the discussion of the results of a measuring campaign which lasted four years on real buildings, and by comparing the reference specific thermal conductance (C) values with those computed on the basis of the measurements. Various tests on the same elements are discussed. Finally an analysis on the influence of the C value on the evaluation of the net heating energy demand of a building in different climates is presented. [Copyright &y& Elsevier]

Abstract: Recent results show that a predictive building automation can be used to operate buildings in an energy and cost effective manner with only a small retrofitting requirements. In this approach, the dynamic models are of crucial importance. As industrial experience has shown, modeling is the most time-demanding and costly part of the automation process. Many papers devoted to this topic actually deal with modeling of building subsystems. Although some papers identify a building as a complex system, the provided models are usually simple two-zones models, or extremely detailed models resulting from the use of building simulation software packages. These are, however, not suitable for predictive control. The objective of this paper is to share the years-long experience of the authors in building modeling intended for predictive control of the building''s climate. We provide an overview of identification methods for buildings and analyze their applicability for subsequent predictive control. Moreover, we propose a new methodology to obtain a model suitable for the use in a predictive control framework combining the building energy performance simulation tools and statistical identification. The procedure is based on the so-called co-simulation that has appeared recently as a feature of various building simulation software packages. [Copyright &y& Elsevier]

Evaluation methods can be used to determine what constitutes good energy performance in a building. With an increasing focus on energy use of buildings worldwide, this evaluation assumes a fundamental importance. This paper provides a comprehensive review of the available methods for analysing, classifying, benchmarking, rating and evaluating energy performance in non-domestic buildings. Methodologies are grouped in five categories: engineering calculations, simulation, statistical methods, machine learning and other methods. Techniques for evaluating buildings are described, their principal applications are shown and limitations are identified. The use of performance evaluation in energy efficiency programmes and standards is mapped. There is a need to further develop interactions between the main modelling techniques to produce simple, robust and validated models. Also, evaluation techniques must be developed to consider comfort or service provision in the buildings as a factor in energy performance. [ABSTRACT FROM AUTHOR]

Abstract: In the tropics, daylighting from a side window requires shading to intercept direct sunlight from the window whilst allowing penetration of daylight from sky. In this paper, daylighting from a double-pane glazed window with enclosed horizontal slats (slat window) was investigated for which it is situated on either north or south wall of a room. Full-scale experiments and simulations were conducted to characterize distribution of the interior daylight from the slat window under a real tropical climate. Performance of the slat window was evaluated in terms of the “useful daylight illuminance” (UDI), interior daylight availability and light power density (LPD) of an integrated dimmable lighting system. Empirical formulas were developed for determining annual average LPD values of the dimmable lighting system over its served area. The LPD value can be used with a reduced form of the energy equation of Thailand's building energy code to evaluate the reduced annual electrical energy consumption for accreditation of the daylight use in a building. The analysis of life cycle cost proved that the daylighting from the slat window integrated with the dimmable lighting system is cost effective. [Copyright &y& Elsevier]

Abstract: This paper develops an overall methodology for investigating the thermal and power behaviors of semi-transparent single-glazed photovoltaic window for office buildings in Hong Kong. In order to estimate its overall energy performance, this study is conducted in terms of total heat gain, output power and daylight illuminance. Three simulation models are established, including one-dimensional transient heat transfer model, power generation model and indoor daylight illuminance model. A typical office room reference is chosen as case study, and the weather data from 2003 to 2007 from the Hong Kong Observatory are used as the simulation inputs. By incorporating the simulation results, the overall energy performance can be evaluated in terms of electricity benefits corresponding to five orientations of the studied typical office. The priority of office orientation considering overall energy performance is: south-east, south, east, south-west and west. The findings show that thermal performance is the primary consideration of energy saving in the entire system whereas electricity consumption of artificial lighting is the secondary one. The overall annual electricity benefits are about 900 kWh and 1300 kWh for water-cooled and air-cooled air-conditioning systems respectively. The application of semi-transparent PV glazed window can not only produce clean energy, but also reduce building energy use by reducing the cooling load and electrical lighting requirements, which definitely benefits our environmental and economic aspects. [Copyright &y& Elsevier]

Abstract: The building sector is an energy intensive sector, with great potential to reduce energy needs and environmental pollution. Several measures are being taken to increase the energy efficiency and avoid energy consumption in this sector. A recent trend is the nearly zero energy buildings, which was already adopted by some of the latest regulations, such as the 2010 recast of the European Performance of Buildings Directive (EPBD). However, to reach these goals, especially considering the existing building stock, new retrofit solutions are required, which must be well adapted to the specific building stock needs, and ensure that the building retrofit can achieve the nearly zero energy buildings standards. This paper presents a new prefabricated retrofit module solution for the facades of existing buildings, and also the steps taken to optimise its performance, which includes a judicious choice of materials, 3D modelling, cost–benefit analysis, use of different simulation tools for performance optimisation and prototyping. It is also shown the implementation of the retrofit module within an integrated retrofit approach, whose final goal was to obtain a building with the minimum possible energy consumption and greenhouse gas emissions. [Copyright &y& Elsevier]

Abstract: Currently, focused efforts are being made to determine the influence of windows on the energy consumption and economy of high-rise buildings. Certain window designs and appropriate glazing systems reduce building energy consumption for heating and cooling and contribute to building economy. This paper addresses double-glazed window units that are composed of tinted glass; clear reflective glass; low emissivity (low-e) glass; and smart glass (one surface consists of a high-performance, heat-reflective glass, and other surface has a low-emissivity coated). These materials reduce the heating and cooling loads of buildings by providing solar control and heat conservation. The aim of this study was to investigate the effects of these alternative units, rather than readily available double-glazed units, in two types of flats. The flats have the same construction and operating system, but they have different plan types with regard to building energy consumption and building economy as it relates to life cycle cost analysis. For this study, we selected buildings in Trabzon, in Climate Region II of Turkey, due to its moderate-humid climate. F- and C-type high-rise residential blocks, with flats composed of two to three bedrooms, constructed by the Republic of Turkey’s Prime Ministry Housing Development Administration of Turkey (TOKİ) are used as models for the simulation. The flat plans in these blocks are modeled using DesignBuilder v.1.8 energy simulation software. The simulation results show that smart-glazed units and those with low emissivity glazing are the most efficient alternatives with regard to building energy consumption and economy. [Copyright &y& Elsevier]

Abstract: Many parameters have been used to evaluate the thermal performance of envelope wall/roofs, most of them for air-conditioned buildings. In this paper, the interest is focused on parameters to assess the thermal performance of envelope wall/roofs for non air-conditioned buildings. Five groups of parameters, some previously used and some newly proposed, have been analyzed. To test the evaluation parameters, numerical simulations of the periodic heat transfer through five different roof configurations have been carried out. This research shows the suitability of the energy transferred through the wall/roof during a day, the decrement factor, the discomfort degree hours, and the hot (or cold) thermal performance index to be used for thermal evaluation of wall/roofs in non air-conditioned buildings. The sensitivity of these parameters with climatic conditions and with the outdoor surface solar absorptance is analyzed. Additionally, it has been shown that the steady-state thermal transmittance, the thermal admittance modulus, the periodic thermal transmittance modulus, and the surface decrement factor, calculated with surface temperatures, are not suitable parameters to evaluate wall/roofs in non air-conditioned buildings. [Copyright &y& Elsevier]