PR2001

Following calculations of potential energy savings, several types of earth-air heat exchangers have been coupled to buildings in novel concepts for passive heating and cooling of ventilation air. For the first time this technology was used in the Belgian climate. In a first case one short plastic tube is coupled to the HVAC system of an office building, to preheat/precool the fresh ventilation air. Measurements are presented on this system and it is shown that performance could have been improved by more concern during the design stage.

Earth-air heat exchangers can be used to reduce energy consumption in building ventilation systems. The idea is to pre-heat air in winter and pre-cool air in summer using the thermal capacity of the soil. To do this concrete and plastic tubes are put underground, through which the ventilation air is drawn. In this paper a 3D unstructured finite volume model is derived, which allows evaluating the earth-air heat exchanger. The model solves conduction through the soil and the convection from air to the tube wall.

Dynamic insulation is a very good example of a ventilation system integrated with the building envelope. The paper describes two recent studies carried out at Nottingham on dynamic insulation. One study concerns a system based on mechanical ventilation. The other describes a purely natural system. Although there are few existing applications of dynamic insulation, it is argued that there is potential for both systems, particularly with certain types of building. The natural system is technically more challenging than the mechanical system, but the potential energy savings are larger.

DCV systems have proved to be energy saving with correct IAQ in previous studies. In order to achieve correct performance, these systems must be properly designed and tested. The purpose of this study is to identify the possibility of using presence sensors based on movement detection to evaluate the number of people present in a room, and also gather some more information about the real occupation rate of meeting rooms. For that, an experiment in several kinds of meeting rooms, located in different buildings and having different uses has been run.

The Coolhouse project is exploring the viability of alternatives to air-conditioning in southern European countries using innovative passive and low energy cooling and ventilating techniques, with an emphasis on ground cooling. The project will demonstrate a variety of passive cooling techniques and the use of ground cooling systems for housing in Crete and Portugal, a nursing home in southern France and a community centre in Italy. The project partners include architects, energy designers, social housing providers and developers, the project will last 48 months.

This paper summarizes part of the work held at ENTPE within the framework of the IEA Annex 35 project. The aim of the work is to develop and experimentally evaluate control strategies for hybrid ventilation systems to provide comfortable indoor environment and good air quality by combining the best aspect of natural and mechanical ventilation. To reach this target and asses the physical model elaborated in this project, a test cell "HYBCELL" has been designed within the laboratory.

Ventilation plays an important role in the RT 2000 regulation. The ventilation system is of course taken into account, but also the building envelope airtigthness on which this paper focuses.

This paper briefly exams the role of the building envelope in determining the internal environmental conditions in buildings and the scope for holistic design of building services and building envelope. It then looks at how holistic design may be undertaken, the barriers to be overcome to enable this to happen and the incentives that are necessary.

We investigate the airtightness of 12 French non-residential buildings, by means of experimental fan-depressurization tests. For this study, 12 recent large (volume > 500 m 3 ) buildings have been chosen according to the construction structure and the activity. Four categories of buildings have been selected : hotels, schools, offices and polyvalent halls. We assessed the air leakage rate of each building, with a fan-depressurization equipment, following the recommendations of the international norm project ISO 9972.

The NEN 5128 "Energy performance of dwellings and residential buildings- Determination method" [1] describes a procedure to calculate the energy performance coefficient EPC. The requirements are given in the Dutch Building Decree [2]. The energy performance is expressed as an Energy Performance Characteristic (EPC). In this EPC procedure ventilation and air tightness play an important role. This paper describes the role of ventilation and air tightness in the Energy Performance Standard. Moreover it gives the alternative way of the so called equivalence principle.