FE-jan10-p14:FE-jan10-p14.qxd 23/12/2009 10:47 Page 14
Feature Compressed air
How to save on energy bills
Gelpack Industrial has made an annual saving of over 45%
on energy used to generate compressed air using a retro-fit
variable speed drive package from EnergAir
A
compressed air audit conducted single ‘target pressure’ set point,
at Gelpack Industrial revealed thereby keeping the system at optimal
40.18% of the input energy used pressure without generating excess air.
to power the compressors was Paul Burns, for Gelpack Industrial,
not productive and the system pres- says: “EnergAir was able to show how
sure was kept above what was a variable-speed drive, sensor feed-
required. This was due to the ineffi- back and a basic communication box
cient operation of two fixed speed, could almost halve the cost of running
75kW compressors, which were used the system. Recommending a retro-fit
on a rotating system to provide com- VSD package rather than a new com-
pressed air to the factory. The audit pressor also made costs manageable.”
highlighted the potential savings that
could be made by retro-fitting a vari- Actions and results
able speed drive (VSD) package to In order to improve the site’s effi-
reduce offload running and match air ciency it was recommended Gelpack
generation to system demand. retro-fit a VSD to one of the existing
In the current climate it is essential compressors. Gelpack opted to install
all businesses reduce energy use. One an EnergAir Solutions retrofit variable
area that can use a lot of non-produc- speed drive and control package that
tive energy is compressed air genera- ensured the system synchronised per-
tion. Many companies are still fectly between the two compressors.
unwittingly operating systems very EnergAir’s drives and controls package
inefficiently through excessive com- is able to maintain the mechanical
pressors idling and unnecessarily integrity of the compressor and actu- Gelpack used a seen in the first year. The installation
over-pressurising systems. Careful ally enhance electrical protection, retro-fit variable was so successful the group company
management of a compressed air thereby ensuring the upgrade would speed drive from Gelpack Excelsior has also now com-
system can therefore lead to savings not adversely affect the compressor. Energair to cut pleted a similar upgrade.
and a reduction in carbon footprint. Installing the VSD resulted in a sub-
down on
Burns says: “With the new EnergAir
Suspecting that this was the case stantially lower peak current draw and
compressed air
system it is simple to manage the com-
with its own system, Gelpack less non-productive energy usage.
energy bills
pressed air system. The energy savings
Industrial commissioned an audit to Using the VSD to generate compressed it produces has made the ire site far
test its compressed air system’s effi- air that matches demand has meant more economical. As well as the sav-
ciency. The audit lasted a total of 187.9 Gelpack has seen massive savings since ings, we are also eligible for a govern-
continuous hours, during which data installation. The system now runs with ment grant that meant a discount on
was logged every five seconds. The over 92% efficiency, at all times keep- the equipment purchase.”
site consists of two 75kW compres- ing within 0.21 bar of the optimal
sors, both of which were fixed-speed system pressure. This increased effi-
The system now
Questions to be asked on sites
compressors. The audit revealed ciency has reduced annual energy costs
runs with over 92%
With the economic climate affecting
40.18% of the energy used to run the by over 45%, saving over £15,000 pa.
efficiency, at all
most manufacturing and increasing
compressed air system was non-pro- With the savings the EnergAir times keeping with- focus on energy conservation, it is
ductive. The pressure in the system system has generated the equipment in 0.21 bar of the important to consider ways in which
also fluctuated between 7.64 bar and had paid for itself within a matter of optimal system to reduce energy wastage. It is essen-
8.63 bar - the optimal system pressure months, meaning real savings were pressure tial to ask questions of a current
for the site is 6.97. system to identify where improve-
Demand for compressed air on most ments can be made: Ask has the
sites will fluctuate. Fixed-speed com- demand profile been mapped? Are the
pressors will produce the same compressors on the site the right com-
amount of compressed air regardless bination of sizes? Has energy use been
and regulate between a loaded (low recorded and benchmarked so the
pressure set point) and unloaded (high impact of any changes made can be
pressure set point) state, consequently validated? Are multiple compressors
a large amount of energy is wasted on being controlled by an effective man-
unloaded running. A variable speed agement system? Is a new VSD com-
drive connected to a control pressure pressor the right solution, and can its
feedback loop is able to measure the capability to save energy be realised?
demand precisely, regulate com-
pressed air generation and replace low EnergAir Solutions T:01932 343638
and high pressure set points with a
www.energair.com Enter 308
14 JANUARY 2010 Factory Equipment
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56