Smart-ready service V-3 · Ventilation
Free cooling with mechanical ventilation system
In short
- 1This page addresses free cooling with mechanical ventilation, a smart-ready service within the Ventilation domain of the Smart Readiness Indicator.
- 2The service has four functionality levels, ranging from no automatic control to control based on temperature and humidity combined.
- 3This service is not covered under method A, the simplified version of the SRI, but only under the full method B.
The levels
Level 0
No automatic control
Level 1
Night cooling
Level 2
Free cooling: air flows modulated during all periods of time to minimize the amount of mechanical cooling
Level 3
H,x-directed control: The amount of outside air and recirculation air are modulated during all periods of time to minimize the amount of mechanical cooling. Calculation is performed on the basis of temperatures and humidity (enthalpy)
What is free cooling with mechanical ventilation?
Free cooling means a building uses cool outdoor air to cool indoor spaces without requiring mechanical cooling equipment. In a mechanical ventilation system, air supply occurs through fans and ducts rather than natural airflow. The smart-ready service V-3 assesses how effectively that system can reduce the amount of mechanical cooling needed.
The Smart Readiness Indicator (SRI) assigns this service to the Ventilation domain, one of nine domains in which the methodology organizes building systems. Within that domain, the focus is on how well installations communicate with each other and with the building's requirements.
What functionality levels exist?
The service has four levels, numbered 0 to 3. At level 0 there is no automatic control: everything happens manually or not at all. Level 1 adds night cooling, where cool night air is used to pre-cool the building.
At level 2, air volume flows are continuously modulated to minimize mechanical cooling. This is called free cooling in the strict sense. Level 3 goes one step further: the quantity of outdoor air and recirculated air is continuously adjusted based on both temperature and humidity. This calculation based on enthalpy, the combined energy content of air, is called h,x-controlled regulation.
What does a higher level mean in practice?
A higher level means the ventilation system responds more precisely to actual indoor and outdoor conditions. This can reduce energy consumption for cooling without compromising indoor comfort.
How does this service factor into the SRI score?
Each smart-ready service is evaluated against seven impact criteria, including energy efficiency and comfort. This service is not covered under method A, the simplified assessment with 27 services, but only under the full method B with 54 services.
This means V-3 counts only when a building is assessed using the full methodology. The building's final score falls into one of seven classes, ranging from below 20 percent to 90 to 100 percent.
Relevant for these building types
Next step
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