outlet to the point of use. Thus at a
pressure of 7 bar, the pressure drop should
be less than 0.7 bar.
Review compressed air usage
Compressed air is energy intensive to run,
and cheaper options exist for certain jobs.
For example, there may be more energy-efficient
alternatives for drying and
ventilation. However, for applications
where there are risks of explosion or
electrical interference, compressed air
remains the best option.
Train and involve staff
BCAS recommends simple awareness
sessions to advise staff about the costs and
safe use of compressed air. For example,
not allowing benches or equipment to be
cleaned down with compressed air will
save a significant amount of air being
vented into the atmosphere. It is far safer
to carry out such cleaning using a vacuum
system to reduce the risk of injury.
Optimise compressed air use
If compressed air is appropriate for the job,
could it be delivered more efficiently? If air
knives feature open-ended pipes, fitting a
venturi-type nozzle can use 30 percent less
compressed air. By making the operation
much quieter, it will improve the working
Air distribution network - zoning
Not all parts of the network operate to the
same hours or the same pressure, so it is
worth separating the compressed air
system into zones. At the same time,
redundant pipework should be isolated.
When replacing piping, consider all the
alternatives to the usual galvanised steel.
Aluminium and plastic pipes do not
corrode and also have a much smoother
internal finish causing less pressure drop
and thus saving energy.
Don’t over treat air
Treating air to remove dirt, water and oil is
necessary but can use a lot of energy.
Many processes only need a proportion of
the compressed air to be treated to a very
high purity. In these cases, excellent
savings are achievable be treating all the
generated air to the minimum acceptable
level and improving the purity (quality) to
the desired level at the usage point.
Service and maintain
Low cost, regular maintenance will help
retain low leak rates and reliability of
equipment. Users should consider a policy
that specifies that energy efficient options
are purchased when replacing all
equipment – whether it is a basic drain
valve through to the actual compressor unit
Finally, it is important to specify the
manufacturer’s genuine spare parts and
avoid the temptation of cheaper
alternatives, realising significant savings in
excess of 25 percent.
- BCAS’s ‘Reducing Energy Consumption
from Compressed Air Usage’ best practice
- BCAS’s ‘The Filtration and Drying of
Compressed Air’ best practice guide
Tel: 020 7935 2464
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