DESCRIPTION OF THE SESSION
Ventilation accounts for approximately 20% of the global energy use for providing an acceptable indoor environment. The requirements for ventilation in most standards and guidelines assume acceptable quality of (clean) outdoor air.

Worldwide, there is an increasing number of publications related to air cleaning and there is also an increasing sale of gas phase air cleaning products. This puts a demand for verifying the influence of using air cleaning on indoor air quality, comfort, well-being, and health. It is thus important to learn whether air cleaning can supplement ventilation with respect to improving air quality i.e., whether it can partly substitute the ventilation rates required by standards. Finally, the energy impact of using air cleaning as supplement of ventilation needs to be estimated.

This project focuses on gas phase air cleaning and does not include filtration.

In many locations in the world, the outdoor air quality is so bad that it is better to avoid ventilation with outdoor air. In such case, the alternative is to substitute ventilation with air cleaning so that the indoor air quality can be kept high.

Even when outdoor air quality is good, the use of air cleaning substituting ventilation with outdoor air could reduce the rate of outside air supplied indoors and thereby energy for conditioning (heating/cooling) the ventilation air, filtration and for transporting the air (fan energy) can be saved.

The session will focus on the energy performance of gas phase air cleaning. Standalone air cleaners may improve air quality by delivering a certain Clean Air Delivery Rate (CADR). For the same level of air quality, the ventilation rate can be reduced by a similar amount. However, standalone air cleaners are also using energy. Air cleaners build into the ventilation system may increase pressure drop and using some power, which both increase the energy use.

A couple of studies based on models and dynamic building simulations on energy use for heating, cooling, and ventilation have been used to study the overall energy implications of using gas phase air cleaners. The results will be presented and discussed in this session.

  OBJECTIVES OF THE SESSION

• Introduce IEA EBC Annex 78
• Present and discuss energy performance of build in gas phase air cleaning technology.
• Present and discuss energy performance of standalone air cleaners.
• Present key performance indicators (KPIs) for the energy performance

  SESSION PROGRAMME

1. 1. Introduction to IEA EBC Annex 78,  Bjarne W. Olesen, International Centre for Indoor Environment and Energy, Technical University of Denmark, Denmark
   2. Air purification as an alternative to increased ventilation in office buildings. Alireza Afshari, Department of the Built Environment (BUILD), Aalborg University Copenhagen, 
   3. Exploring the Energy-Saving Benefits of Gas-Phase Air Cleaning in Nordic Buildings, Sasan Sadrizadeh, Fluid and Climate Technology, KTH Royal Institute of Technology, Stockholm, Sweden
   4. Gas phase air cleaning effects on ventilation energy use and KPI’s for Energy Performance, Dragos-Ioan Bogatu, International Centre for Indoor Environment and Energy, Technical University of Denmark, Denmark

  SESSION CHAIRS

1. 1. Bjarne W. Olesen, International Centre for Indoor Environment and Energy, Technical University of Denmark, Denmark
   2. Sasan Sadrizadeh, Fluid and Climate Technology, KTH Royal Institute of Technology, Stockholm, Sweden

  SESSION DURATION

  –75 minutes