demand-controlled ventilation

The thermo-hygrometric treatment related to the air change in buildings requires a relevant quota of the total energy demand for heating and air conditioning, especially when the ventilation exigency is significant. For this reason a correct energy saving strategy should always focus on the use of suitable techniques in order to reduce this consumption. For example, as the modern comfort science teaches, more flexible values can be accepted for the internal humidity set point without compromising indoor comfort conditions.

Demand-controlled ventilation has been proposed to improve indoor air quality and to save energy for ventilation. It is important to estimate occupancy in a building precisely in order to determine adequate ventilation airflow rates, especially when people are the major source of indoor contaminants such as in office buildings. In this paper, we investigate occupancy estimation methods using a dynamic neural network model based on carbon dioxide concentration in a space.

In this study the multifamily demonstration buildings with demand controlled ventilation systems are discussed. Furthermore,the heating systems together with demand controlledventilation are looked at.There are given examples of the centralized supply and exhaustventilation system, the centralized exhaust ventilation systemand the apartment based ventilation system. All the Systemsare mechanical, natural ventilation is not discussed here. Incold climates natural ventilation, i.e.

The IEA Annex 18 Demand Controlled Ventilation Systems (DCV-Systems) with 9 participants is midway through its work program. Reviews are indicating possible energy savings in the range of 8%-40% both in experiments and in theoretical studies. Most of the case studies will start this autumn with sensor tests, test room studies, and trials in occupied spaces. The conditions in dwellings and offices with various ventilating systems will be simulated in the test rooms. Almost 30 occupied buildings will be involved in tests in dwellings, offices,auditoria and schools.

The IEA Annex 18 Demand Controlled Ventilating Systems-(DCV-Systems) with 9 participants are just in the middle of the work. Reviews are indicating energy conservation possibilities in the range of 8-40% in experiments and even more in theoretical studies. Most of the case studies will start this autumn with sensor tests, test room studies, and trials in occupied spaces. In the testrooms will be simulated the conditions in dwellings ---and offices with various ventilating systems. Almost 30 occupied buildings will be involved in tests in dwellings, offices, auditoria, and schools.

In the framework of a project of the International Energy Agency (IEA) , IEA-Annex XVIII - Demand Controlled Ventilating (DCV) Systems, which started in fall 1987, a review of the state of the art of already existing DCV systems and devices has been undertaken by all participating countries. This paper is concerned with air quality sensors which may be suitable to control air quality on demand. The dominant contaminants are not only variing in different kinds of buildings (dwellings, schools, stores etc.) but also from room to room due to different ways of utilizing the spaces.