In Europe, an estimated 87TWh of all industrial electricity is used for the generation of compressed air, emitting about 84,000kt of CO2 annually.

Compressed air is often referred to as the fourth utility in industry. However, generating compressed air is a huge burden on power and therefore impacts operating costs as well as CO2 emissions. Everybody understands the importance of making efficiency improvements but often, advice is simply reactive:

• Find and fix leaks;
• Change filter elements;
• Switch off when not in use.

By reducing the delivery pressure, it is recognised huge savings can be achieved. The shift to reducing facility pressure is already taking place at some large manufacturing plants.

Why wait to act? SMC proposes the 4-bar factory to provide real change and are here to help you make a transition to making a reduction in power consumption possible.

Contributors to inefficiency

Several common factors are often identified to impact on compressed air efficiency in the factory:

• Remove causes of pressure drops for supply;
• Improve isolation;
• Prevent inappropriate use;
• Remedy leaks;
• Reduce pressure;
• Ensure the right air quality;
• Recover energy;
• Improve compressor utilisation.

 Almost all these improvements relate to a reduction on compressor duty.

With compressors set to maintain a factory pressure, any air consumption will naturally increase the compressor’s duty. The higher the pressure, the higher the consumption. When we reduce consumption pressures, we reduce air volume consumption and reduce compressor duty. However, it is common for eradicating leaks to be prioritised as a 'quick fix'.

Looking beyond air leaks

Leaks are often in places that are difficult to access such as inside guarded machinery or on high up distribution pipe networks. As factory machinery and infrastructure ages removing leaks is largely unachievable. Leak rates may be high but often do not represent a huge contribution in energy consumption.

Why lower pressure?

Reducing the supply pressure is not feasible without first a full review of the local demands on the compressor. A system to handle surges in flow demand is critical. By capturing and reviewing pressure and flow data during operation it’s possible to identify areas for improvement.

For every 1-bar reduction in delivery pressure, an average of 6-8% less specific power is consumed. The advice from compressor suppliers is to keep the working pressure as low as possible. Reducing the delivery pressure by 1 bar across industry can offer estimated CO2 emission reductions of about 6,700kt in Europe alone.

If you want to accept the challenge of reducing site operating pressure, SMC is here to help and will:

• Work with you to access existing equipment and make proposals for improvements;
• Work together with you and your suppliers to ensure that new or upgraded machinery can operate at lower pressures;
• Review the effectiveness of your existing air delivery system;
• Assist in the development of design specifications to ensure new machinery is future-proofed for the 4-bar factory.

Accept the challenge today!