English

We conducted observations of wind velocity profiles above a high-density area in Tokyo, Japan, using a Doppler LIDAR system. Obtained data of the exponent index for the power law, which is commonly used to describe the wind velocity profile, displayed diurnal variation, decreasing in the daytime, which is expected in unstable atmospheric conditions. This paper provides information on the uncertainty in the calculated ventilation airflow rate due to the use of a constant value for the exponent index.

With a tighter building envelope more minimal influences come into consideration. As how the thermal and hygrothermal properties of the materials may improve the ventilation or whether the dust distribution is altered with the new surface temperatures and flows and of course how all other new chemicals which we introduce to living environments affects the IAQ. Preferably the in situ measurement data from the filed campaigns and case studies will be defined as ST5 in Annex 68.

The objectives of Subtask 4 are to develop design and control strategies for energy efficient ventilation in residential buildings which ensure high indoor air quality. The strategies must go beyond the current common practice and actively utilize recent research findings regarding indoor air pollutants and combined heat, air and moisture transfer as well as benefit from recent advances in sensor technology and controls.

The objectives of Subtask 3 Modeling are to improve the understanding and develop prediction models on the impacts of outdoor pollutants, thermal environment, building materials and envelope, and indoor furnishing and occupant activities on the indoor air quality, and the energy necessary to achieve the desired IAQ level in residential buildings, considering the IAQ metrics and pollution loads to be developed in Subtask 1 and 2, respectively.

First the Subtask will organize a literature survey and make researcher contacts to gather relevant data and existing knowledge on major pollutant sources and loads in buildings, including models. Laboratory testing and model setup to provide examples of new types of data which shall be beneficial to improve knowledge on combined effects that must be taken into consideration in order to achieve new paradigms for energy optimal operation of buildings.

Subtask 1 of IEA EBC Annex 68 will aim at defining the metrics to enable a proper consideration of both energy and IAQ benefit in building design and operation

The overall objective of the IEA EBC Annex 68 is to provide scientific basis usable for optimal and practically applicable design and control strategies for high Indoor Air Quality (IAQ) in residential buildings. Naturally, those strategies should ensure minimal possible energy use. The project aims to gather existing and provide new data on pollution sources in buildings, model the indoor hydrothermal conditions and air quality as well as thermal systems, and will look to ways to optimize the provision of ventilation and air-conditioning.

In the frame of the European project called Bricker, a new prototype of single room ventilation with heat recovery has been developed. This new unit is supposed to be installed in class rooms of an educational institution. This paper deals with the development of the first prototype of this unit. An empirical model of such device is also proposed in order to be coupled with a building model. This aims at determining the seasonal performance of the device and thus the potential energy saving (compared to other technologies) resulting from its use.

The energy use in buildings is dependent on the choices made during the design, construction and renovation. The causes for these differences are, among others, caused by the behavior of the occupant of the building and the choice of heating and ventilation system. The European scheme of Energy Performance Certificates (EPCs) aims at reducing the energy use in the built environment. It is most common to calculate (i.e. not measure) the energy use for the buildings which are affected by the scheme.

Ventilation systems can save heat energy by using heat recovery, but consume electrical energy to power the fans. In practice, the energy efficiency of those systems can be lower than expected, when compared to the nominal values provided by the manufacturer. In this paper, results of a comprehensive field tests with 20 centralized and 60 decentralized ventilation systems for residential buildings and the calculation of the primary energy savings of those devices are presented.