hybrid ventilation system

By using natural driving forces, hybrid ventilation systems reduce fan energy consumption in buildings. They are of increasing interest as they help to improve buildings energy efficiency while ensuring good indoor environmental quality. However, the performance of these systems is variable and dependent on climatic conditions. Besides, the plurality of openings, variable airflows, and unstable flow patterns make the measurement of the performance of natural or hybrid ventilation systems a challenging task.

Zero Energy Buildings require airtightness and mechanical ventilation systems to provide air changes and energy saving. These requirements contrast with the principles of natural ventilation. Through a case study located in Modena, Italy, a design strategy is proposed as a solution to integrate natural and mechanical ventilation systems at different times of the year to reduce the energy consumption in a newly designed high-density ZEB. The internal comfort evaluation for the warm season is then verified with a multizone dynamic simulation and a CFD analysis.