Characteristics values of natural ventilation and air conditioning.

This investigation is part of project NATVENT TM, a concerted action of nine institutions of seven European countries under the Joule-3 program. It aims to open barriers that blocks the use of natural ventilation systems in office buildings in cold and moderate climate zones. The choice to apply natural ventilation in office buildings is very arbitrary; it depends very much on the personal preference of the architect or taken for budgetary reasons, even sometimes not considered at all. This article proposes a method to compare natural ventilation with more complicated mechanical ventilation systems based on reliability, comfort, initial and maintenance costs and energy consumption. It shows clearly the strong points (cheap, reliable) and the weak points (limited cooling capacity) of natural ventilation.