Hybrid ventilation. Development of design methods and control strategies. Phase 1
This project is phase 1 of the Danish contribution to the international project IEA-ECBCS Annex 35: HybVent - Control Strategies for Hybrid Ventilation in New and Retrofitted Office Buildings. Annex 35 started with a one year preparation phase August 1, 1997, followed by a four year working phase from August 1, 1998 to July 31, 2002.
Design of energy-efficient ventilation systems in office buildings is often turned into a question of using either natural ventilation and passive cooling or mechanical ventilation and cooling. This prevents a widespread use of sustainable technologies because a certain performance cannot be guaranteed under all conditions. In fact in the large majority of the cases a combination of systems would be beneficial depending on outdoor climate, building design, building use, and the main purpose of the ventilation system. Suitable design tools are not available for sustainable ventilation systems as it is the case with mechanical systems. Valid design tools would give architects and engineers the necessary confidence in system performance which in many cases is the decisive factor for choice of system design. The present project is the first phase of the Danish contribution to IEA ECB and CS Annex 35 HybVent - Control Strategies for Hybrid Ventilation in New and Retrofitted Office Buildings, which will be carried out from 1/8-1998 to 31/7-2002. Annex 35 will have the Department of Building Technology and Structural Engineering. Aalborg University, as Operating Agent. The research project aims at a better knowledge of the use of sustainable ventilation technologies and is focusing on development of control strategies and design tools for hybrid ventilation in new and retrofitted office building and promotion of energy and cost-effective hybrid ventilation systems, in office and educational buildings. Hybrid ventilation is ventilation systems where mechanical and natural forces are combined in the ventilation of buildings. Control strategies are ways to control hybrid ventilation dependent on building design, internal loads, natural driving forces, outdoor conditions and season to fulfil the immediate demand to the indoor environment in the most energy-efficient manner. The project approach includes in the first phase a state-of-the-art review of sustainable ventilation technologies, available design methods and applied control strategies and algorithms. The potential for sustainable ventilation in new and retrofitted office and educational buildings will be assessed. Principles for control strategies for hybrid ventilation will be developed and a hybrid ventilation system will be design for a new or retrofitted office building. The results of the first phase will be presented at a seminar and in articles in relevant magazines
The project objective is to promote the application of hybrid ventilation in office buildings in Denmark, to improve existing design methods, to develop a new probabilistic analysis method for prediction of potential and capacity of hybrid ventilation on a yearly basis, and to develop control principles and strategies for hybrid ventilation in office buildings, which ensure optimal use of natural driving forces and which at the same time ensure fulfillment of indoor air quality demands, thermal comfort demands and energy and environmental demands. The project is divided in a number of parts, each with a specific objective. Phase 1 contains the following parts: State-of-the-art of hybrid ventilation, which include a review of existing buildigs and systems and of buildings codes and regulations. The review has identified weaknesses and areas with lack of knowledge. All results are collected in the report: State-of-the-art of Hybrid Ventilation. Development of probabilistic analysis method for hybrid ventilation, which has focused on development of a new method to predict hybrid ventiaion performance, that takes into consideration the typical variations in outdoor climate, loads, etc. Development of control strategies and principles for hybrid ventilation in office buildings, which has focused on development of principles and strategies for fan-assisted natural ventilation. Demontration of hybrid ventilation performance in office buildings in Denmark, where energy consumption and indoor climate has been investigated for a whole year in an office building. The result shows a very good indoor climate. However, the energy consumption for heating is at the level of the requirements in the Danish Building Regulations (BR95). The results will be included in the work in the following project phases, 2 and 3
Key figures
Category
Participants
| Partner | Subsidy | Auto financing |
|---|---|---|
| Aalborg Universitet (Fredrik Bajers Vej) | ||
| ESBENSEN RÅDGIVENDE INGENIØRER A/S |
Contact
Sohngårdsholmsvej 57
DK-9000 Aalborg, Denmark
Heiselberg, Per (lektor), 96358080, ph@civil.auc.dk
Øvr. Partnere: Statens Byggeforskningsinstitut; Esbensen Rådgivende Ingeniører
