This paper focuses on hybrid ventilation performance in an office building. It presents measurement results from the new headquarters of the company Bang & Olufsen, which served as one of the case study buildings in IEA ECBCS Annex 35. Ventilation and control strategy, as well as operational experience of the hybrid ventilation system is presented. Measurement results include long-term values of temperatures, CO2 and energy use for assisting fans and heating of ventilation air as well as electricity use for appliances.
The characteristics of a hybrid air-conditioning system, utilising natural and mechanical 'task' ventilation, are investigated in an office setting. The characteristics of the indoor environment are examined by means of CFD (Computational Fluid Dynamics) simulations under various conditions of incoming outdoor air. The control of the task air conditioning system (VAV system) is included in the calculation through changing the supply air volume to keep the task zones temperature at a target temperature.
This study, which formed part of the Annex 35 Hybrid Ventilation in New and Retrofitted Office Buildings project, was completed at LEPTAB and supported by the French Research Ministry and the ADEME (Agence De lEnvironnement et de la Matrise de lEnergie). It consisted of modelling a typical classroom and comparing different control strategies to estimate the performance of a hybrid ventilation system for different climates.