Cleanroom energy consumption is highly dependent on room conditions. The system works paradoxically, such as the cooler being on to dehumidify and at the same time the heater to keep the temperature of the dried air acceptable. Cooperation is necessary.
Chiller
The chiller has a dual function in air treatment. The temperature and relative humidity must be monitored and must not exceed certain limits. In the design phase, we agree on the margins within which this is done.
Climate changes
Those agreements are based on the use of the clean room, but also the outside conditions. If the outdoor climate changes because summers get warmer and winters get colder we will have to adjust values.
Energy Consumption
Cleanroom energy consumption follows from room conditions, internal heat load and outside air conditions. This determines the capacity of the equipment.
Relative humidity
What determines cleanroom relative humidity? Usually that question is answered by the product buyer’s industry. Each industry has its specific room conditions. Aerospace, food industry, Semicon, pharmaceuticals? For example, effervescent tablets are very sensitive to moisture or the paper strip in the Carona test (<30% RH?). In pharmaceuticals, food industry or healthcare, moisture and temperature affect the sterility of the room. (+/- 55% RH?)
Setpoint
Depending on the cleanroom application, the set point of relative humidity and temperature is determined as well as the maximum and minimum levels.
Cleanroom chiller supplies cold water of a temperature that guarantees adequate dehumidification. Usually this temperature is too low for a pleasant working environment. Cleanroom energy consumption increases significantly if the temperature of the dehumidified air is too low for a pleasant working environment and therefore needs to be reheated.
But summer cleanroom operators appear to select a lower room temperature than in winter(?!) The wind chill apparently also plays a role.
Cleanroom chiller uses energy to cool, but heating is needed to then make the room temperature comfortable again. Thus, double energy is used: cooling and heating.
Cleanroom chiller, the capacity of the chiller is selected on what is needed to dehumidify the freshly drawn outside air and what is needed to compensate the internal heat load. A high recirculation rate of cleanroom air keeps energy costs low and if possible; place all “hot” equipment outside the cleanroom.