Optimising HVAC Systems

Typically a HVAC system’s energy consumption accounts for more than 40% of a commercial building’s total energy usage. So it’s no wonder Facility Managers, Estate Managers and Operations Directors are exploring ways to optimise HVAC efficiency.

Quick wins like changing filters on schedule and doing regular maintenance will make small improvements, but there are other ways to maximise energy efficiency. What are they? Well, our Energy Improvement Managers recommend these three things…

Control Loop Optimisation – make sure that the control loop for the AHU (Air Handling Unit) system has been set to your building requirements and not left on the factory setting. Your controls system contractor can optimise these control loops to the system, saving on energy and prolonging the life of components.

Dead Band Control – having heating and cooling on simultaneously, or a constant cycle between the two, wastes energy and reduces the life of a HVAC system. Eliminate the possibility of this by introducing a dead band control. A dead band is where no heating or cooling is running, saving you energy.

Fan Speed Reduction – the AHU motor should be controlled by a VSD (Variable Speed Drive). One way to reduce energy usage is by reducing the speed of the fan and the air flow rate. Fan Law 3 of the Fan Affinity Laws states that changing the fan speed by X will impact the horsepower threefold. So decreasing the fan speed by 10% will reduce energy consumption by 30%. There is a minimum speed that you can set the VSD control to prevent the motor overheating, but considerable savings can be achieved.

Although it might look like things are running efficiently, there are always ways to improve and increase business energy efficiency, reducing carbon emissions and costs. If you want to explore how you can tackle your own hidden energy waste, get in touch with one of our experts today.