How to make your HVAC more efficient

Businesses are willing to spend a large portion of their annual operating expenses on heating, ventilating, and air-conditioning (HVAC) because it helps to create comfortable work environments which are conducive to higher employee productivity. In fact, HVAC can account for over 40% of energy consumption in your building. Through improved control and management of ventilation, temperatures, and system usage, facilities managers and data centre operators can optimise HVAC energy consumption and greatly reduce costs.

While most facilities managers and data centre operators understand how the high expense of cooling impacts the business’ bottom line, they lack the proper resources and knowledge to build an optimally energy efficient cooling system and operate it at a lower cost.

Schneider Electric’s free online Energy University course, ‘HVAC Efficiency and Equipment Optimisation’, can help you get the knowledge you need to maximise the efficiency of your HVAC equipment. The course clarifies what’s needed to promote efficiency.

HVAC plant must be capable of meeting a wide range of demands for cooling and humidity control in the summer to heating in the winter so may seem oversized for any particular season.  One practical method to provide a wider range of control and save energy is to introduce variable speed motor drives to the system.

Variable speed drives (VSDs) also contribute to the building’s overall comfort level by optimising and regulating air flow and temperature into the building’s occupant space. Unlike a fan that runs either full speed or off, a variable speed drive can run at all speeds in between, allowing facilities managers and building occupants more control to adjust the temperature.

Many plant owners are confused how variable speed drives such as the Altivar 212 and Altivar 61 save them money as opposed to fans being thermostatically controlled.

How do VSD’s use less energy?

Without a speed controller, motors are stopped or running at full speed, and airflow or water flow are controlled by valves of vanes. A VSD reduces the speed of the motor controlling the fan or pump when full flow is not required, thereby reducing the power and the electrical energy used.

A 10% lower motor speed reduces power consumption by 27%

Due to the way motors work, as motor speed falls, the reduction in electrical energy required to drive the motor is determined by the cube law.  Simply put, reducing the motor speed by 10% reduces the power required by the motor to 90% x 90% x 90% =72.9% of the energy used at full speed. Similarly, a reduction to 80% then will provide 49% reduction in the energy used.

 Go here for Schneider Electric VSDs