A hybrid ventilation strategy is part natural and part mechanical. Passivent’s hybrid ventilation equipment has air tempering and mixing units and an energy-efficient fan which is used when required. It has three modes of operation:
In winter, colder spring and autumn periods the hybrid ventilation equipment tempers the incoming air with warmer internal air before it enters the space, thereby minimizing the risk of cold draughts for the occupants. By mixing and utilising any excess of heat gains within the space there is no need to use additional energy to warm the fresh air. Warm internal air enters the unit at ceiling level and is also discharged across the ceiling once mixed to ensure thermal comfort levels are the highest possible.
In peak summer conditions, the energy efficient, low power fan can be activated to promote air movement, keeping the ventilation strategy operating and the temperature under control. When the building encounters high heat gains, the fan can be activated to purge the space more rapidly than a passive ventilation system. The fan speed will automatically adjust to suit the temperature and CO2 requirements within the space.
Due to the low airflow resistance of the system the hybrid equipment is able to operate in a passive mode without any need for fan assistance. This is a highly cost-effective mode due to the lack of energy required to motorise the fan unit.