Air compressors for a cleaner world

In view of soaring energy prices and ambitious climate-protection targets, modern industry is experiencing unprecedented pressure to make production processes as efficient as possible. In addition to this, companies also have to maintain and increase their competitive edge, as well as strive to ensure sustained economic success.

This latter objective can only be achieved, however, through significant energy savings and through drastic reductions in CO₂ emissions. It is here that compressed air, one of the main sources of energy for modern production, can help make a significant contribution. Thankfully, today’s technology provides compressed air users with a myriad of ways to reduce energy consumption and to minimise CO₂ output. Innovative products, in addition to forward-thinking solutions, also play a key role.

Energy costs taken over the lifetime of any air compressor can add up to 70% of the initial capital cost. Investing in efficient compressed air systems has a higher impact on energy consumption than any other factor. Through these efficiencies it is possible to reduce the compressed air creation costs by more than 30%.

Kaeser’s screw compressors are fitted with the Sigma Profile airend, which is claimed to deliver power savings of up to 15% compared with conventional screw airend rotor profiles. The use of MEPS electrical motors has further contributed to reducing energy consumption and CO₂ emissions. A direct drive eliminates transmission losses associated with gear or belt-driven systems as the drive motor and compressor airend rotate at exactly the same speed.

Master controllers, too, are essential to coordinate the operation of a compressed air system and cut the compressors in or out according to air demand, subsequently maximising energy efficiencies. In order to fully tap into a compressor’s efficiency potential, every energy-affecting parameter has to be taken into consideration. To achieve maximum efficiency, it is necessary to minimise the amount of energy consumed as a result of pressure flexibility, switching and control losses. Compressed air management systems featuring the latest simulation software are able to implement the appropriate control strategies accordingly. Operational data reporting including energy demand and machine load are available for energy-management purposes.

Controllers must also monitor the system for maintenance purposes to provide a basis for plannable, demand-oriented maintenance, balancing the operating hours of the machine and recording malfunctions to bring down servicing costs and increase reliability. Kaeser has the Sigma Controller and Sigma Air Manager to manage and control all aspects of a compressor system.

Measuring air needs and on/off duty cycle is essential when measuring wasted energy. Often, the duty cycle of the compressors is only 50% and many users are not aware of this as their compressor has an indicator showing only the hours in operation, but not the hours under load.

Also, leakages can occur in every air network, affecting flow, pressure and air quality. Poor choices in pipe materials, diameter and layout cause flow restrictions, often resulting in significant pressure drop. Pressure drop is a main cause of increased energy consumption and underperforming air-driven tools and equipment. If not rectified, these losses can add up to considerable additional energy consumption and therefore costs - leakage rates of 10 to 25% are not uncommon.

Kaeser’s engineering ability to analyse all aspects of an operating system through air demand analysis (ADA) and Kaeser energy saving systems (KESS) provides the user with an exact insight into their air losses through all stages of production, ultimately improving energy efficiency and reducing CO₂ emissions.