Are industrial workplaces being cooled efficiently?

Many industries provide cooling for their personnel and machinery. Some machineries (CNCs, panels, VFD rooms, server racks, etc.) also have their own dedicated cooling systems (DX-based systems). Both humans and machines operate within the same workspace, which is cooled by an HVAC system.

In such cases, the heat rejected by the machines’ cooling systems is often released into the building space. This heat is then removed again by the building’s HVAC system.

In this situation, the heat rejected by the condenser units of the machines is essentially wasted energy. This waste heat should ideally be discharged into the open environment rather than into the conditioned building space.

Such dedicated cooling systems are required in the CNC machine tool industry (highest usage), in precision machining areas like with laser and EDM machining, in industrial automation and robotics applications, and in steel or foundry or heavy engineering among others.

The driving factors for these machines to have dedicated cooling systems can be one of several including:

• High internal heat load such as servos, VFDs and PLCs that generate significant heat (typically >300–500 W heat inside panel);
• High ambient temperatures such that simple fan cooling is ineffective (Shop floor in India: 35–45°C); and
• Requirement for precision and reliability (precision machining, robots, retrofitted facility)

Under these conditions, the following are recommended best practices (in order of increasing complexity and efficiency):

Option 1: Place condensers of the dedicated DX air conditioning systems outdoors;
Option 2: Duct the condenser heat and discharge to the ambient;
Option 3: Use central HVAC system instead of dedicated DX air conditioners; and
Option 4: Integrate advanced heat recovery systems into the equipment.

At the time of initial and incremental planning, people should evaluate these problems and adopt the most suitable solutions for their workspace to save energy and support sustainability.

In all cases, care should be taken to ensure no condenser heat is discharged in the conditioned space. This is one consideration in a system-level approach needed to design a sustainable industrial workplace.

Fig: Generated by Copilot