Compressed air energy efficiency
How to improve the performance of your compressed air system
There are opportunities to improve efficiency throughout your compressed air system, even before the air is compressed.
Improving air intake quality, generation and control
Ideally, your system will deliver air by the most effective and efficient means according to the demand requirements of your equipment. You can increase the efficiency of your system by introducing more effective generation and control. Doing this also reduces energy wastage and improves the performance of the end-use equipment.
The air that feeds the compressor needs to be as close to outside air temperature as possible. So the location of the air intake is important. Filters in the air intake need to be kept in good condition to prevent a drop in system pressure which could increase energy use by as much as 4 per cent.
Make sure that your system is operating at the lowest possible pressure and your control methods closely match your compressors and the demand requirements of end-use equipment. For example, although cascade pressure control is commonly used to control multiple compressors, an electronic sequential controller is generally more efficient.
Detecting air leaks
All compressed air systems have leaks. Regularly testing your system for leaks is one of the most important ways you can improve energy efficiency and save money.
Reducing impurities in the air taken in by the compressor can improve system efficiency, and can increase the life and performance of end-use equipment. Treating air is energy intensive, so you can improve efficiency by:
- only treating air to the minimum required standard
- correctly installing and maintaining the treatment system, and making sure it's adjusted following any change in demand
- making sure timed solenoid condensate drains are set correctly, or using more efficient no-loss type electric condensate drains instead
Air receivers and distributors
Air receivers in most systems are sized only with the compressor in mind. But it's very important that there's enough 'useful storage' to be able to cope with varying levels of demand so that pressure fluctuations are reduced or eliminated. A distribution system needs to be sized to fit the demand and designed to allow adequate air flow with minimum pressure drop.
Waste heat recovery from compressed air
When air is compressed, a huge amount of heat is generated and often wasted. It's possible to recover most of this heat and use it elsewhere.
Monitor compressed air energy use
It's important to monitor the energy consumption of your system so you can quickly identify if you are wasting energy. To monitor the system effectively, you need to install specific pieces of equipment like pressure gauges and meters.