The present work is part of a research effort aimed at integrating a detailed model of airflow in large spaces with an algebraic multizone infiltration model to describe pollutant transport and coupled air flows within and between complex buildings and large spaces. In the past 15 years, zonal models were developed with the goal to obtain an approximate prediction of airflow characteristics in large indoor spaces. Also, reducing the number of grids in CFD models is a natural way of decreasing their demand of computational resources to solve air flows in room.

Through the analysis of the main international environmental performance rating systems (BREEAM, LEED and GBTool) this work aims to show international design tendencies concerning sustainable building equipment requirements and to provide to designers and researchers a broad view of sustainable building equipment solutions. Hence a particular attention was paid to the assessment approach provided by these systems for each requirement, focussing on the comparison of the building performance to a benchmark, on compliance with qualitative indications or use of best technologies.

Through the analysis of the main international environmental performance rating systems (BREEAM, LEED and GBTool) this work aims to show international design tendencies concerning sustainable building equipment requirements and to provide to designers and researchers a broad view of sustainable building equipment solutions. Hence a particular attention was paid to the assessment approach provided by these systems for each requirement, focussing on comparison of the building performance to a benchmark, compliance with qualitative indications or use of best technologies.

Purpose of this study is establishment of energy efficient natural ventilation system for Japanese conventional wooden single-family house, by using humidity-controlled extract units (code name: GHN).To evaluate the effect on energy performance and indoor air quality by adapting the GHN to the passive stack ventilation system, airflow rate, humidity, temperature and CO2 concentration are measured over a period of one year in an experimental house.

Within the program "Solar Optimized Buildings" which is funded by the German Ministry of Economy (BMWi), a building for the DB Netz AG has been realized and monitored. The design concept of the building is dominated by architectural solutions for ventilation, cooling and lighting of the office rooms. Due to the change of responsibilities during the design and building process, the targeted primary energy consumption of 100 kWh/m 2 y has been exceeded so far. The reasons lie primarily in the inadequate operation of the technical systems for heating, ventilation and artificial lighting.

This paper describes work currently being carried out to evaluate the environmental impact and energy savings potential from the application of passive ventilation cooling in urban buildings. The work is carried out as part of an ALTENER project focussing on solar and passive ventilation for urban buildings. The study involves the collection of information for current building stock in four European countries; UK, France, Spain and Greece.

The natural ventilation potential (NVP) is the possibility, or probability, to ensure anacceptable indoor air quality by natural ventilation only. A passive cooling potential (PCP)can also be defined, as the possibility to ensure an acceptable indoor thermal comfort usingnatural ventilation.

This paper is divided into tree main sections, ‘Introduction to natural ventilation’, ‘Examples, strategies and results’ and ‘Energy consumption’. In the first section a general introduction to natural ventilation is given, including the three main princi

This paper describes current work to undertake a market assessment of the potential for the application of Passive Downdraft Evaporative Cooling (PDEC) to new and existing buildings in Southern Europe. The work is carried out as part of a European funded ALTENER project focussing on solar and passive ventilation for urban buildings. PDEC is a technique that may potentially become a substitute for conventional air-conditioning. The technique avoids the need for ductwork, fans and suspended ceilings, and reduces the need for refrigerant based cooling.

In moderate climates, one promising feature to reduce the energy demand of office buildings for air conditioning without reducing comfort is passive cooling by night ventilation. An office building has been designed, realised and monitored for a long time period in the framework of the German research programme solar optimised buildings. The night cooling of the office building has been realised by natural ventilation.