Labelling of Air Compressors – Much More Than Nameplate Data

Labelling of household appliances has been a success story by delivering information on energy consumption and the lifetime cost of operation of the appliances to private consumers. Energy efficiency labelling has triggered a boost of improvements. This paper addresses the difficulty of comparing energy efficiency data for air compressors, as the compressor manufacturers do not release them. The results demonstrate that a single energy efficiency value per compressor has only a limited value to identify the best product for the application. From the analysis and comparison of fixed speed and variable frequency drive air compressors, it is also demonstrated that compressors with variable frequency drive do not necessarily perform better than fixed speed compressors. The paper also stresses the importance of a compressed air system approach, being necessary to tap the largest energy-saving potentials in compressed air systems. The requirement to release complete data sheets of compressor packages sold in Europe similar to the USA is supported.