The truth about compressed air audits

Regardless of the brand or type of equipment that you currently use on site, the expectation is that any company providing compressed air auditing services would provide a well-rounded and unbiased set of recommendations. While simply typing ‘compressed air audits’ into Google will show an endless list of providers, it is important to exercise caution when choosing a company.

Air audits are routinely provided for free by several companies that are directly involved with the sale of compressed air equipment. Audits are often considered to be ‘sales tools’ that push companies towards specific outcomes. The majority of auditors have either equipment that they hope to sell or existing equipment on the site to protect. In such situations, the best interests of the client may not be a priority. Be aware that dealing with an OEM company that also provides audits carries a set of risks. There is a chance that you could get a biased report that is far from being a well-considered, independent outcome for you as the client - it wastes considerable capital on an ill-fitting solution with a payback that may never be achieved.

What can’t be measured can’t be improved! Reliance on inadequate or inaccurate data often has very costly and long-lasting implications and consequences. To achieve meaningful recommendations, appropriate parameters (power, pressure and flow) need to be analysed at the right frequency - 1-second data intervals are best, with anything more than 5 seconds potentially creating misleading results.

There are important questions to ask of every audit. Does the audit consider pressure and flow variability? Will it consider how the compressor’s performance changes with system demands? Does it cover all areas of your compressed air system? And, most importantly, is your audit report more than just a bunch of lines on a piece of paper?

Smoke and mirrors can often cloud reality, with providers hiding behind a veil of uncertainty. Auditors need to be able to properly demonstrate how the results of an audit can lead to the recommendation, and completely justify the scale of savings.

Some project-based solutions might include major system redesigns or repairs and possibly recommend new or alternative compressor technologies. New compressors are not a ‘magic pill’ that will cure all of the ills of a flawed compressed air system design. Technologies such as variable speed drives, two-stage compression, air treatment and advanced system controllers may be some of the many recommended. Variable speed drives might be suitable for some applications but certainly not for every company’s needs. A VSD compressor could actually cost more to run than a simple fixed speed solution in some situations.

Only after a very detailed review of your entire system’s supply and demand profile will you gain a clear picture of how air is consumed and how efficiently it is generated and distributed to the point of use.

If you’re considering a compressed air audit, it is recommended that you choose a company with a strict adherence to an independent approach. This will provide for a neutral, unbiased and commercially impartial recommendation and ultimately provide the best compressed air solution for your site.

*Quentin St Baker is the National Manager for the Energy Efficiency Services division at CAPS Australia. He has extensive experience in the compressed air industry and has provided assistance to many well-known organisations to identify and implement energy-efficiency solutions. Representing CAPS on the Energy Efficiency Council, Quentin is a mechanical engineer who has undertaken extensive training to make him one of Australia’s leading specialists in the science of compressed air.