ACT Apr-Jun10.p65 - Petroleum Conservation Research Association

advised along with replacement of old
energy inefficient motors with new
energy intensive motors.
Sewage Pumping and
Treatment
Currently, only one sewage treatment plant
(STP) of 25 MLD is in operation for the
ULB and Visakhapatnam being on the east
coast, presently either the treated or
untreated sewage is being let out to sea.
The major observations indentified while
reviewing sewage pumping and
treatment are mentioned in the following
section.
Observations
● Most of the pumps used are very old
with very low level of efficiency and so
there was a requirement of replacement
of old energy inefficient pumps with new
ones. Similarly, energy inefficient motors
need to be replaced with energy
intensive motors.
● Surface agitator type aerators were being
used with large capacity of motors.
● Maintenance cost for rewinding of
motors was very high, as the STP is
located on the beaches of Bay of Bengal
where high moisture levels prevail in
atmosphere.
● The treated sewage was being let out
to sea
Recommendations
● Considering the surface aeration with
compressed air for improving the
Biological Oxygen Demand (BOD) of
the treated sewage was recommended
which would also reduce large size
motors being used for agitating the
sewage water. It would in turn also
reduce the maintenance cost for motors.
● It was also advised to reuse the water
with less than 100 BOD for greenery
instead of letting the same to sea, there
by reducing the usage of sweet water.
The specific energy consumption of
sweet water is more than the energy
consumption for pumping water to tank
trucks.
Street Lighting
There are about 60,000 street lights with
2,628 switching points in 72 wards of ULB.
74% of light fixtures are Fluorescent tube
light (FTL), 14% are 150W High Pressure
Sodium Vapour (HPSV), 7% are 70W SVLs,
3% are 250W High-Pressure Mercury-
Vapor (HPMV) and 2% of them are 250W
& 400 W HPSVs. Street lighting is spread
over 533 sq km of the ULB. The major
observations in this case included:
Observations
● All the cutout controls were without any
protection and were dangerously
installed. In many stretches, even the
spacing between the poles is not
maintained
● Energy meters were not properly
protected / installed.
● Due to multiple fixtures at few junctions
and stretches, zebra effect was observed
and in many areas dark patches were
also observed.
● The overall power factor observed was
very low and it ranged from 0.38 to
0.89.
Recommendations
● It was recommended to replace existing
40W florescent tube with high efficiency
lumen output FTL.
● Providing new control panels with
voltage optimizers, PF compensation
and automatic switching to save energy
was advised.
● It was also suggested to provide
microprocessor controlled automatic
street lighting control including dimming
facility at midnight to early hours and
install automatic timer / photocell unit
for saving energy in lighting system.
● It was also recommended to replace:
i. Existing probe start 250W metal
halide with new 200W energy
efficient pulse start metal halide
including energy efficient control
gear.
ii. Existing probe start 400W MH
lamps with new 320W pulse start
MH lamp including energy efficient
control gear.
iii. Existing electromagnetic control gear
with energy efficient electronic
control gear.
iv. Existing electromagnetic choke with
energy efficient electronic choke for
FTLs.
v. 70W HPSVs with 2x24W T5 FTLs
or LED lighting
Buildings
There are about 516 municipal buildings
including offices, dispensaries, schools,
stadiums, community halls, sulabh
complexes etc. Out of these buildings, 20
buildings were hand picked and audited
through each category of building. The
major observations were:
● Lighting in GVMC Buildings is provided
with incandescent bulbs, FTLs and
CFLs. At the museum, 12V 50W
halogen spot lighting were provided for
the exhibits.
● Standard energy inefficient ceiling fans
and exhaust fans were used in almost
all the buildings.
● Most of the split ACs installed were non
star rated.
Recommendations
● The existing halogen spot light at the
museum was proposed to be replaced
with 12V 35W Infra Red Coated (IRC)
energy efficient spot lights with 500
burning hours, existing incandescent
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active conservation techniques