English

During the past two decades, pressure on the building industry increased gradually. Energy effi-ciency, indoor air quality, comfort, durability, sustainability all became key issues within a framework of growing cost awareness. Hence, this multiplication of issues emphasized the need for a new methodology to assess building quality, called the performance concept. This paper uses performances to evaluate an advanced building envelope system: transparent insulation (TIM).

This paper discusses the use of a building thermal analysis methodology in which the stochastic nature of the external climates and randomness of physical parameters are considered. Methods of thermal calculation which give the density function of the room air temperature and heating and/or cooling loads are proposed. Weather data is modeled by linear time series models with white noises as inputs, which take into account the auto-correlations and cross-correlations of the raw climatic data.

Hollow core ventilated slab systems provide an effective means of utilizing the building structure as a thermal store to reduce energy cost while maintaining the thermal comfort of the occupants. The optimum control strategy for the system would be one that minimizes energy use without prejudicing the thermal comfort requirement. This paper describes the characteristics of the optimal control problem and its potential for reducing energy cost.

The frame work of methodical design as developed at the University of technology Twente is used to specify dynamic system design/configuration concepts and alternatives for HVAC-installations (Heating Ventilation And Air Conditioning). A method of implementing different design representation is integrated into a modelling paradigm. This paradigm describes the design process in terms of several major phases, levels of abstraction and connected levels of modelling centred on layered design representations.

The conservation policies and Rational Use of Energy (RUE) developed until the present, had their origin in the search of a smaller energetic consumption in order to reduce economic costs in a growing prices market of the fuels. Consequently methodologies were developed for the energy saving dimensionment for the residential sector with energetic supply nets.

A dynamic greenhouse climate model was used to simulate the effect of condensation and evaporation on the auxiliary heating requirements, on the inside air humidity and temperature and on the vegetation temperature in greenhouses covered with 12 different cladding materials. Condensation was shown to increase the auxiliary heating requirements for materials having a far infrared radiation transmittance lower than 0.18, while it reduces them for all other materials. Savings ranged between +25 % for PP and -17 % for standard glass.

Room thermal analysis with furniture will generally result in differing heat load values and varying indoor temperatures compared to the same calculation without furniture. This is due to several factors concerning room configuration and its effect on the modes of heat exchange occurring within the indoor environment. The influence of furniture on indoor radiation heat transfer, specifically when computing the peak load of an intermittent heating system, was investigated in this study. The peak load value generally determines the required maximum output capacity of a heating system.

Recent information on CFC's and their impact on the environment has created shockwaves of concern for those who are relying on these products in various applications and a thermal energy storage system can be considered as a useful tool to reduce the initial refrigerant charge by means of minimising the number of refrigeration machinery. A conventional HVAC stand alone ice storage installation may yield capital cost savings through a reduction in refrigeration capacity and possible inherent environmental benefits to be gained from load shifting of electrical energy.

For its new building in Mons, the RTBF (Radio and Television organism of the Belgian French Community) decided, with the help of the Walloon Region, to design several equipments with special techniques characterised by a rational and economical use of energy : primary and noble (electricity) energies and reduced use of CFC.

Modern refrigeration technology including absorption refrigeration has coexisted with the more standard type of vapour compression systems ever since the beginning of refrigeration. Absorption refrigeration mainly requires a heat source to drive its cooling cycle. Only in the USA and Japan is absorption refrigeration widespread in the market, a market tendency of the last decades. Concerns regarding the Global Warming Potential and the more recently defined Thermal Equivalent Warming Impact (TEWI) is an opportunity to further explore the applications of absorption refrigeration.