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The aim of this project has been to provide information on energy consumption in different building categories. Previous studies have focused on total energy use and not on how the consumption of energy is divided in various categories. On a national level, statistical data are generally available in terms like energy consumption per square meter.

Twenty terrace houses without heating system has been built in Sweden. The houses are extremely well insulated and very airtight. They are also quipped with a high efficiency ventilation heat recovery system. The total electricity consumption and the air temperature in two positions has been monitored for each of the houses on an hourly bases. Further has the environmental conditions, i.e. outdoor temperature, wind, sun etc been monitored. In six of the houses separate measurements of electricity consumption for ventilation and hot water has also been performed.

The new perspective technology in building heat supply and climatisation, are given in this paper. The main energy-saving solutions are following: architectural and layout design taking into account the influence of solar radiation and wind direction; high thermal insulation of building envelope and glazing; mechanical supply-and-exhaust ventilation systems for each flat; Ground heat and exhaust air heat recovery for hot water supply; doublepipe heating system for each flat, horizontal, equipped with flat heat meters and thermostatic valves installed at each room heater.

Historically, industrial buildings have been simple constructions with no insulation. Ventilation has been natural through openings in the walls and in the roof. Around 1970 we started investigating airflows in large industrial premises by water model studies. This lead to a better understanding of the ventilation airflow patterns in heavy industries. In the following years, the principles were applied in practice. At the present, more than 30 large plants have been designed according to these principles and valuable experience has been gained.

The annual energy cost and first cost of the HVAC system, life-cycle costs (LCC) and benefits of improved productivity were simulated in an office building located in a cold climate when improvements of air quality were made by increasing the outdoor air supply rate and by reducing the pollution loads. The building was ventilated by a variable air volume (VAV) system with an economizer or a constant air volume (CAV) system with heat recovery. The pollution loads were assumed to be similar to those in a non-low-polluting or low-polluting building.

This paper describes a study of reduced performance of mechanical exhaust systems in 42 Dutch houses after several years of operation. It also describes the effect of reduced ventilation on air quality and the perception and use of the ventilation system by residents. The guanine contents of dust samples taken from the sleeping room were determined to assess the risk of allergy.

Background. A low ventilation rate has been shown to increase the risk for health and comfort problems in offices. However, very few studies have investigated the impact of ventilation rate at home on health effects, (Wargocki et al. 2002). The aim of this study was to investigate if low ventilation rates in homes do increase the risk for asthma and other allergic symptoms among pre-school children in Sweden.

An evaluation of different ventilation principles and their application in various premises like bars and restaurants has been conducted. Measurements of nicotine concentrations revealed a strong dependency on ventilation solutions. In restaurants and bars where the ventilation systems are properly designed it is possible to fulfill requirements issued by the Norwegian authorities.

A number of computer simulation case studies have been conducted with the objective of investigating the potential for energy savings in buildings with variable air volume (VAV) systems and demand controlled ventilation (DCV), compared to buildings with conventional constant air volume (CAV) ventilation systems. The simulation systems have been modelled on a modular form, they are generally very detailed and comprehensive, and they have shown to be able to provide very realistic results compared to real world conditions.

A CO2 level of 1000 ppm is very often used as reference for control and design of ventilation flow rates in buildings. This level is well accepted in practice, and is thus normally not given any further considerations. To retain 1000 ppm CO2 in a room with fully mixed flow conditions, a flow rate of 7 liters/sec per person must be supplied. In many countries, national regulations and standards prescribe flow rates for comfort ventilation that are significantly higher than 7 l/s.