VIP

This report summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries.

Air supplied by ventilation plants and air conditioning systems carries small particles whose size depends on filtration device efficiency.

Mineral, vegetal or biological particles may deposit on the inner surface of air ducts and other air conditioning equipment creating a thin layer of dust. Such dust deposit may deteriorate the quality of the air flow blown into the rooms through the booths and consequently the global indoor air quality in the building.

The role of CO2 to control the indoor air quality in buildings is based on the fact that CO2 developed by people breathing may be used as a marker for the bio-effluents produced by people. The use of CO2 for the steering of ventilation systems is only appropriate in the case that no other pollutant is more dominant for the indoor environment. For instance when a person is taking a shower in a bathroom, moisture will be the more dominant pollutant. Nevertheless the use of CO2 as marker for the indoor air quality is widely used.

For the near future the expectation of experts is that the most promising systems will be based on demand-controlled hybrid ventilation technologies. The impact of further development and the improvement of fully mechanical or fully natural ventilation systems on energy savings and indoor air quality is reaching its limits. The hybrid part of the system is of course the minimisation of the electric power of the fan by improving the fan efficiency and low pressure ducting.

Born with the energetic crisis, humidity controlled ventilation has been introduced in regions with a moderate climate as a means to fight condensation problems induced by tighter building construction and lower heating temperatures.
This paper develops the means and goals of humidity controlled ventilation in the framework of the building energy reduction.
Why have a variable airflow? 
Why chose humidity as the driving parameter? 
How does humidity controlled ventilation work? 

This paper summarises presentations and discussions that took place during the workshop entitled “Trends in national building ventilation markets and drivers for change” held in Ghent, Belgium, in March 2008 with a specific focus on innovative (ventilation) systems. Before this workshop, experts were asked to provide information regarding their national situation and the difficulties they experienced to improve the situation in terms of market penetration of innovative systems, indoor air quality and energy use requirements, and compliance check schemes.