How to prepare for a compressed air energy
The compressed air energy audit comes in all shapes and
sizes, from free and basic to full system audit with specific
measurements, such as leak detection, power and flow rate,
maintenance review and more.
In this editorial, Imtiaz Rastgar highlights that even though
inexpensive audits are available, but one should be cautious of
how they are performed. Many compressor manufacturers offer
audits at no charge and use it as a tool to make further sales.
He advises that a customer should choose an independent air
audit company which can give impartial advice. The author
presents some of the tips in order to prepare for an energy
There are five main questions, one should ask the prospective
- Do you have a reference or previous customer information
so that one can talk and evaluate the details?
- Will you help evaluate the complete system, supply and
- What kind of report will you supply?
- Will you help remedy the inefficiencies?
- Will you offer a post audit and perhaps an annual PM
Another key element to consider before employing a company to
perform an audit is a that this audit can be performed when the
system is running normally. There is usually no need for
downtime during an audit.
Which Type of Audit Do you need?
Often, the audit you choose depends on the type of operation
and the budget available. Audits generally fall into three
- Basic Audit (walking the line).
- Data Logging.
- Full System Audit.
A basic audit includes a visual inspection of the compressed
air system and is often available from compressor manufacturer
at no charge and used as a tool to make further sales of
compressors. In this context, care should be exercised in
choosing an independent air audit company which can offer an
The data logging involves performance tracing of the
compressor system for a minimum of seven days, which often
reveals if the compressor is correctly sized or if it is
operating at its optimal CFM output. While data logging does
come with a cost, one should always check with their local
utility providers for available rebates or incentive programs.
A full System Audit can cost up to PKR 1,500,000 to 2,000,000
depending on the nature of the audit, but typical savings range
from 30% to 50% when the audit recommendation is put into
practice. The full system audit often includes air measurement
of compressed air demand, air leak detection and control and air
quality, the benefits include lower energy costs and higher
production efficiency. This is usually paid for the fee paid for
the audit. Large users of compressed air, with connected loads
of 500 kW and above stand to gain immensely from waste reduction
occurring through leaks and other inefficiencies in the
compressed air system.