What advantages does mechanical ventilation have over simply opening windows?

Natural ventilation through manual window opening is impractical, difficult to manage and energy-consuming. A mechanical ventilation system allows you to fully automate stale air removal and fresh air intake, delivering continuous indoor air purification and greater energy efficiency.

Ventilation management using controlled mechanical ventilation systems (CMV) is preferable to simple window opening because air flows can be precisely managed, the incoming air can be filtered for pollutants and annoying air currents and external noise are prevented. Forced ventilation systems ensure effective and continuous “scrubbing” of pollutants through dilution, which means they are removed as they form and cannot accumulate. Pollutants include CO2, moisture (the main cause of mould) and all other undesirable biological processes.
In addition to removing pollutants, controlled mechanical ventilation can be used to manage thermal loads (i.e. to transfer heat to and from closed rooms).