Energy Efficiency of Air Compressors
Most air compressors lose energy efficiency as the demand for air decreases. In extreme cases, up to 65% of the nominal power consumption can be used unnecessarily.
Variable Speed Drives and Energy Savings
Purchasing a variable speed drive (VSD) compressor or upgrading existing compressors can significantly save energy and finances.
Typically, the power of the compressor is regulated by controlling the inlet or outlet valves, which limits its output, although it continues to operate at maximum RPM.
In positive displacement compressors, the most effective approach is to adjust the output power by changing the speed.
Thus, by reducing air consumption, energy consumption is also reduced.
Business Case
Many companies gain significant financial benefits from installing variable speed compressors or retrofitting them with a frequency converter. The costs for such modernization can be recouped in less than four years.
Benefits of Variable Speed Drives
- Improved efficiency compared to fixed speed compressors at loads up to 75%.
- Elimination of pressure fluctuations, which often reduce system pressure to 0.5 bar, leading to additional energy savings.
- Speed regulators provide "Soft start" — eliminating high starting currents.
- When using multiple compressors in the system, variable speed regulation of one compressor allows other fixed speed compressors to operate with optimal efficiency at a base load.