A passive or natural cooling system that employs night purge ventilation (also known as night cooling or night flushing) is a low-energy and cost-efficient way to cool your building without compromising on comfort.
Cooling systems in buildings are used to keep the temperature of your structure from exceeding specific temperatures during warm weather, or where there are significant thermal gains (such as solar gain, people and equipment). This cooling is often referred to as comfort cooling.
In comparison to mechanical cooling systems that use a significant amount of energy to cool down the air that is inside the building, natural cooling systems with night purging make use of the free and chilled night air outside to cool down the building during the night, so it has the ideal temperature when occupants start using the building in the morning.
During the day, either automated natural ventilation or hybrid ventilation (also known as mixed mode ventilation) can be employed to keep the temperature at comfortable levels.
When passive ventilation methods are used for your cooling system, you automatically reap the benefits of the free and clean resources provided by the nature.
To supplement cooling systems during the day (this can be either active cooling systems based on mechanical HVAC solutions or passive cooling systems based on green technology such as automated natural ventilation or mixed mode ventilation) night purging can be applied.
The benefits of choosing a green cooling system with night purge ventilation includes:
Natural night ventilation is driven by the natural driving forces of the wind and/or thermally (stack) generated pressures.
The heat absorbed by a building's exposed thermal mass during the day is released to the indoor air at night, after which it is purged by night ventilation. Meanwhile, external fresh air cools down the thermal mass, which then acts as a heat sink during the following day.
Using night flushing as a cooling system involves automatically operable windows or louvres being opened for a pre-set period of time over night, allowing a natural air flow through the building.
Besides using automated natural ventilation with night purging, devices such as solar shades, reflective surfaces, insulation and green roofs can reduce thermal gains.
Solar shading is a particularly effective way to improve your overall cooling system strategy, and can be incorporated and controlled by the natural ventilation system for a holistic an intelligent solution.
Contact WindowMaster for more information about cooling systems with automated natural ventilation and night cooling. We have more than 20 years of experience with intelligent buildings and natural cooling systems.