Centrifugal compressor optimization for savings

 Centrifugal compressor

The energy effectiveness of centrifugal compressors is based, among other things, on their excellent output regulation properties. When the compressor is dimensioned and adjusted correctly for consumption, optimal compressed air output is achieved.
It is important for the customer’s processes to keep the compressed air production steady and thus energy efficient.
You should evaluate the advantages of the entire system, not just the performance of an individual device or operating point. Even if a single device is energy efficient, a poorly controlled production entity may not be it.
Compressed air consumption can vary widely at different process stages. The advantages of a centrifugal compressor will be lost if it is not properly dimensioned and adjusted to the system and consumption variations.
Centrifugal compressor vs. screw compressor
The compressing force of the centrifugal compressor is based on the variation of the velocity of the flowing gas.
  • In principle, a centrifugal compressor is much more energy efficient than a screw compressor.

  • The life of a centrifugal compressor can be more than 30 years, and its efficiency does not drop over time as with a screw compressor.

  • Maintenance costs of a centrifugal compressor are lower than those of a screw compressor.
Centrifugal compressor regulation
  • Regulating the output of a centrifugal compressor is not quite as simple as that of a screw compressor. With the help of Sarlin Balance control system, the centrifugal compressors output can be easily regulated as long as the centrifugal compressors control unit is equipped with external pressure setting control.

  • Sarlin has delivered dozens of output regulation solutions to centrifugal compressors. The combined energy saving of the compressor with Sarlin Balance control system is typically 20-30%.

  • Sarlin Balance also reports possible alarms, provides information on compressed air consumption and fluctuations, and manages the various components so that the air production is as energy efficient as possible.
To be considered when sizing a centrifugal compressor


  • In which units is the output given?
  • Under what conditions is the output given, e.g. what is the intake air temperature?
Intake air temperature
  • Motor power should be sufficient even when the intake air temperature is cooler.
  • Cooler intake air increases motor power requirement and compressor output. Higher output can only be utilized if the temperature is taken into account when sizing the compressor.
Regulation range of compressor capacity
  • The width of the regulation range of a centrifugal compressor depends mainly on the design pressure of the compressor.
  • The higher the design pressure, the wider the regulation range.
  • In practice, however, a compromise is often worthwhile: sacrificing a percentage or a couple of the efficiency gives more flexibility. It is a misconception that a centrifugal compressor should run full capacity all the time.
  • The capacity regulation range must be known in order to make the control as efficient as possible.
Can we help you choose a centrifugal compressor?
Centrifugal compressors are already available in the 150 kW size range, so even smaller compressed air consumers can enjoy their benefits. They are most needed in large-scale compressed air production, where Sarlin is a leading supplier.
Regular optimization and maintenance of the compressed air system keeps the compressed air production and plant production process running without disruption. Compressed air is an expensive source of energy, and Sarlin’s task is to keep the compressed air production even and the customer’s electricity bill as low as possible. If factory production stops due to disruptions in compressed air supply, the cost of production loss will be too high. This risk should not be taken.