A Report on Energy Audit for Electrical & Mechanical Utilities
Conservation of energy
also protects our
environment.
A Report on
Energy Audit For
Electrical &
Mechanical Utilities
Conducted at
A’Safwah Dairy & Beverages Co.,
Salalah, Sultanate of Oman
Table of Contents
A. Objective and the details of the equipment .......................................................................................... 12
B. Audit team .............................................................................................................................................. 13
C. Preface .................................................................................................................................................... 14
1. ENERGY DETAILS OF THE PLANT ............................................................................................................. 24
1.1 Background and Process Description .............................................................................................. 24
1.2 Production ....................................................................................................................................... 24
1.3 Electrical Infrastructure and Consumption ..................................................................................... 25
1.4 Fuel Consumption ........................................................................................................................... 26
1.5 Specific Energy Consumption – PET plant ....................................................................................... 27
2. ELECTRICAL POWER MEASUREMENT & ANALYSIS OF DISTRIBUTION SYSTEM ..................................... 29
2.1 Electrical Power Distribution and Capacitor Watt Loss .................................................................. 29
3. ENERGY PERFORMANCE ASSESSMENT OF ELECTRICAL UTILITIES ......................................................... 31
3.1 Ice Bank Chilled Water Plant – Dairy Plant ..................................................................................... 31
3.1.1 Chiller ...................................................................................................................................... 31
3.1.1 Circulation Pumps ................................................................................................................... 32
3.1.2 Observations and Recommendations ..................................................................................... 33
3.2 York Chilled Water Plant – PET Plant .............................................................................................. 33
3.2.1 Energy Performance Assessment – York Chilled Water Plant ................................................ 33
3.2.2 Observations and Recommendations ..................................................................................... 35
3.3 Aoki 1 & 2 Mould Cooling Chilled Water Plant – PET Plant ............................................................ 35
3.3.1 Energy Performance Assessment – Aoki 1 & 2 Mould Chilled Water Plant ........................... 35
3.3.2 Observations and Recommendations ..................................................................................... 36
3.4 Aoki 3 Mould Cooling Chilled Water Plant – PET Plant ................................................................... 37
3.4.1 Energy Performance Assessment – Aoki 3 Mould Cooling Chilled Water Plant ..................... 37
3.4.2 Observations and Recommendations ..................................................................................... 38
3.5 Air Compressor – Dairy Plant .......................................................................................................... 38
3.5.1 Energy Performance Assessment – Air Compressors – Dairy Section .................................... 39
3.5.2 Observations and Recommendations ..................................................................................... 40
3.6 Air Compressors – PET Plant ........................................................................................................... 44
3.6.1 Energy Performance Assessment – Air Compressors – PET plant .......................................... 44
3.6.2 Observations and Recommendations ..................................................................................... 45
3.7 Lighting Load ................................................................................................................................... 47
4. ENERGY PERFORMANCE ASSESSMENT OF THERMAL UTILITIES ............................................................ 48
4.1 Boiler – Dairy Plant .......................................................................................................................... 48
4.1.1 Energy Performance Assessment - Boiler ............................................................................... 48
4.1.2 Observations and Recommendations ..................................................................................... 49
4.2 Heat Loss Assessment from Boiler and Steam Distribution Pipeline – Dairy Plant ....................... 51
5. ENERGY PERFORMANCE ASSESSMENT OF BLOW MOULDING MACHINES ............................................ 53
5.1 Blow Moulding Machine – 1 ........................................................................................................... 53
5.2 Blow Moulding Machine – 2 ........................................................................................................... 53
5.3 Blow Moulding Machine – 3 ........................................................................................................... 53
5.4 Blow Moulding Machine – 4 ........................................................................................................... 54
5.5 Observations and Recommendations ............................................................................................. 54
6. AL NAJD AGRICULTURAL DEVELOPMENT CO. – ENERGY AUDIT ............................................................ 55
6.1 Production ....................................................................................................................................... 55
6.2 Electrical Infrastructure and Consumption ..................................................................................... 55
6.3 Specific Energy Consumption .......................................................................................................... 56
6.4 Electrical Power Measurement ....................................................................................................... 58
6.5 Illumination ..................................................................................................................................... 59
6.6 Energy Performance Assessment of Submersible Pumps .............................................................. 60
6.6.1 Energy Performance Assessment – Irrigation Submersible Pumps ........................................ 60
6.6.2 Observations and Recommendations ..................................................................................... 62
7. TECHNICAL EVALUATION AND FEASIBILITY FOR RENEWABLE ENERGY ................................................. 65
7.1 Site Details....................................................................................................................................... 65
7.1.1 Location ................................................................................................................................... 65
7.1.2 Information on Available Grid Power ..................................................................................... 65
7.1.3 Building/roof information relating to the facility ................................................................... 65
7.2 Project at A Glance .......................................................................................................................... 66
7.3 System Components ....................................................................................................................... 66
7.4 Scope of Work ................................................................................................................................. 68
7.5 Solar Power Plant Layout ................................................................................................................ 68
7.6 Other Details ................................................................................................................................... 69
7.7 Structural Anchoring ....................................................................................................................... 69
7.8 Inverter Installation ......................................................................................................................... 70
7.9 Safety Guidelines followed by us .................................................................................................... 71
7.10 Exclusion (Scope of Client) .......................................................................................................... 72
7.11 Delivery Schedule ........................................................................................................................ 72
7.12 Pricing Overview ......................................................................................................................... 73
7.13 Panel Layout ................................................................................................................................ 75
7.14 Month-wise Generation .............................................................................................................. 76
7.15 Simulation: .................................................................................................................................. 76
7.16 Annual Production ...................................................................................................................... 77
7.17 Pricing Overview ......................................................................................................................... 78
8. ANNEXURE .............................................................................................................................................. 82
8.1 Power Analyser Graphs for Transformers ....................................................................................... 82
8.1.1 Transformer No. 1 ................................................................................................................... 82
8.1.2 Transformer No. 2 ................................................................................................................... 82
8.1.3 Transformer No. 3 ................................................................................................................... 83
8.1.4 Transformer No. 4 ................................................................................................................... 83
8.1.5 Transformer No. 5 ................................................................................................................... 84
8.1.6 Transformer No. 6 ................................................................................................................... 84
8.2 Process Flow Diagrams.................................................................................................................... 85
8.2.1 Fresh Juice except Orange ...................................................................................................... 85
8.2.2 Orange Juice ............................................................................................................................ 86
8.2.3 Laban Drink ............................................................................................................................. 87
8.2.4 UHT Plain and Flavoured Milk ................................................................................................. 88
8.2.5 Fresh Milk ................................................................................................................................ 89
List of Figures
Figure 1. Production vs. Month (Bottles, Bags and Caps) chart ........................................................... 25
Figure 2. Pie Chart – Transformer wise (kW) ........................................................................................ 25
Figure 3. Pie Chart – PET plant .............................................................................................................. 26
Figure 4. Pie Chart – Dairy Plant ........................................................................................................... 26
Figure 5. Specific Energy Consumption – PET plant .............................................................................. 28
Figure 6. Rhodes Grass Production ....................................................................................................... 55
Figure 7. Electrical Distribution – Pie Chart – Hanfeet Farm ................................................................ 56
Figure 8. Specific Energy Consumption – Hanfeet Farm ....................................................................... 57
Figure 9. Grundfos Submersible Pump Curve ....................................................................................... 63
Figure 10. KSB Submersible Pump Curve .............................................................................................. 64
Figure 11. Solar Photovoltaic System .................................................................................................... 69
Figure 12. Solar Panel Layout ................................................................................................................ 75
Figure 13. Month-wise Electricity Generation – Solar PV plant ............................................................ 76
Figure 14. Annual Generation – Solar PV Plant ..................................................................................... 77
Figure 15. Power Graph – Transformer 1 (kW-Red, kVAr-Green, kVA-Blue) ........................................ 82
Figure 16. Power Graph – Transformer 2 (kW-Red, kVAr-Green, kVA-Blue) ........................................ 82
Figure 17. Power Graph – Transformer 3 (kW-Red, kVAr-Green, kVA-Blue) ........................................ 83
Figure 18. Power Graph – Transformer 4 (kW-Red, kVAr-Green, kVA-Blue) ........................................ 83
Figure 19. Power Graph – Transformer 5 (kW-Red, kVAr-Green, kVA-Blue) ........................................ 84
Figure 20. Power Graph – Transformer 6 (kW-Red, kVAr-Green, kVA-Blue) ........................................ 84
Figure 21. Process Flow Diagram – Fresh Juice except Orange ............................................................ 85
Figure 22. Process Flow Diagram – Orange Juice .................................................................................. 86
Figure 23. Process Flow Diagram – Laban Drink .................................................................................. 87
Figure 24. Process Flow Diagram – UHT Plain and Flavoured Milk ....................................................... 88
Figure 25. Process Flow Diagram – Fresh Milk...................................................................................... 89
List of Tables
Table 1. LPG Consumption from Jan-18 to May-18 ........................................................................... 27
Table 2. Specific Energy Consumption – PET plant ........................................................................... 27
Table 3. Details of Power Measurement of the Electrical Distribution system for different
transformers of the plant .................................................................................................................. 29
Table 4. Watt Loss of Capacitors ....................................................................................................... 29
Table 5. Energy Performance Assessment – Ice Bank Chilled Water Plant ....................................... 31
Table 6. Energy Performance Assessment – Chilled Water Circulation Pumps ................................ 32
Table 7. Energy Performance Assessment – York Chilled Water Plant ............................................. 33
Table 8. Energy Performance Assessment – Aoki 1 & 2 Mould Cooling Chilled Water Plant ........... 35
Table 9. Energy Performance Assessment – Aoki 3 Mould Cooling Chilled Water Plant ................. 37
Table 10. Energy Performance Assessment – Air Compressors – Dairy Section ............................... 39
Table 11. Energy Performance Assessment – Air Compressors – PET plant ..................................... 44
Table 12. Lighting Load ...................................................................................................................... 47
Table 13. Energy Savings in Lighting with LEDs ................................................................................. 47
Table 14. Energy Performance Assessment of Boiler ........................................................................ 48
Table 15. Flue Gas Analysis at Chimney Sampling Point ................................................................... 49
Table 16. Heat loss assessment - Boiler ............................................................................................ 51
Table 17. Energy Cost-Benefit Analysis for Insulation ....................................................................... 52
Table 18. Energy Performance Assessment of Blow Moulding Machine – 1 .................................... 53
Table 19. Energy Performance Assessment of Blow Moulding Machine – 2 .................................... 53
Table 20. Energy Performance Assessment of Blow Moulding Machine – 3 .................................... 53
Table 21. Energy Performance Assessment of Blow Moulding Machine – 4 .................................... 54
Table 22. Specific Energy Consumption – Hanfeet Farm .................................................................. 57
Table 23. Current Illumination Scenario ............................................................................................ 59
Table 24. Energy Savings by LEDs ...................................................................................................... 59
Table 25. Energy Performance Assessment – Irrigation Submersible Pumps .................................. 60
Table 26. System Description ............................................................................................................ 68
Table 27. CAPEX and OPEX cost for Solar PV plant ........................................................................... 78
Table 28. ROI for Solar PV Plant ........................................................................................................ 79
List of Photos
Photo 1. Air Compressor – Dairy Section .............................................................................................. 38
Photo 2. Indicative photograph for compressed air use in plant ......................................................... 42
Photo 3. Drain Valve of Air Receiver ..................................................................................................... 43
Photo 4. Pressure gauge on Air Receiver tank ...................................................................................... 43
Photo 5. Damaged Insulation at boiler pipelines .................................................................................. 50
Photo 6. Feed Water tank ..................................................................................................................... 50
A. Objective and the details of the equipment
a. Objective
1) Study and understand activities in the plant and locate energy cost centres.
2) Study historical energy consumption in case of electrical energy and other fuels used along
with material processed and comment on specific energy consumption trends.
3) Study and understand electrical single line diagram of the distribution network inside the
premises. Check and record electrical power quality pattern at all major feeders.
4) Study current harmonic contents for compliance requirements as per IEEE 519-2014 standard.
5) Study and comment on reactive power compensation. Suggest remedies for harmonic
mitigation and maintaining unity power factor.
6) Prepare kW and kWh Pie chart for energy consumption of all major plant processes by
physical measurements to locate significant use of energy and contribution of an individual
process.
7) Walk-through audit of Thermal systems and comment on specific energy consumption by
comparing with theoretical and industry benchmark consumption.
8) Walkthrough energy audit of utilities like cooling towers, compressors and use of compressed
air, other cooling systems, air handling equipment to locate possibilities of energy saving.
9) The present report on the above data and analysis recommending energy-saving
opportunities along with locating area, where detail audits are required to quantify exact
gains versus required investments.
“.. the greenest power is the power
you dont have to produce..”
PAGE| 12 www.fosterms.com
b. Details of Equipment Used
Table 1. Name of Equipment used in the Audit
No. Name of the Equipment Model Make Use
1 Power Analyser ALM 36 Krykard Measurement of Electrical
Parameters
2 Power Analyser ALM 35 Krykard Measurement of Electrical
Parameters
3 Portable Flue Gas FEM-7 Technovation Analysis of flue gases after burning
Analyser of different fuels
4 Ultrasonic Flow Meter Orflo Measurement of flows of fluids
passing through pipes
5 Infrared Camera Testo Thermal Images for measuring
temperatures
6 Sling Psychrometer Ajanta Electric & Measurement of Dry Bulb and Wet
Refrigeration Co. Bulb Temperatures
7 Pressure Gauge Micro Measurement of gauge pressure
B. Audit team
Foster Consultants Mr. Rahul Deshpande (Lead Energy Auditor, Electrical, Utilities)
Mr. Makarand Kulkarni (Lead Energy Auditor, Mech, Thermal)
Mr. Suresh Kshirsagar (Electrical Engr. & Renewable Energy Expert), Mr.
Dheeraj Deshpande (Energy Domain Expert)
Mr. Rushikesh Kshirsagar (Electrical Engineer)
Back Office Team:
Mr. Swapnil Lotake (M. Tech. Energy Technology)
Mr. Siddharth Lad (Electrical Engineer)
Ms. Mamta Kudale (Electrical Engineer)
A’Safwah Dairy & Beverages Entire Team of M/s A’Safwah Dairy & Beverages Co.
Co.
www.fosterms.com
PAGE| 13
C. Preface
We have been allotted an assignment of Walk Through/Preliminary Energy Audit at M/S. A’Safwah
Dairy & Beverages Co., Salalah, Oman.
We thank you for the belief shown in us. We appreciate the initiative taken by the
management in energy saving.
Our Electrical, Mechanical and Thermal team has worked independently on both the sides.
We are presenting a report based on measured energy data and historical data related to
energy consumption collected from the plant during the audit.
An effort has been made to calculate specific energy consumption for material conversion
along with assessing first level efficiencies of utility equipment like compressors, cooling
towers, chillers, AHUs etc.
We have made an attempt to analyse present energy recording and energy monitoring
system prevailing in plant and have included our comments regarding the same. We strongly
recommend computerized EMS system communicating with strategic energy meters installed
in the plant. This would generate timely energy data with accuracy automatically and would
allow staff to work on energy conservation than on just logging the history. Such a system can
even generate specific energy consumption figures on daily basis.
The audit team had individual experts in electrical, utility and thermal field, as such expert
third-party evaluation of energy use was done in the plant and this report is prepared on the
basis of this evaluation.
We are thankful to the management and Maintenance team for providing a sincere and
enthusiastic support to all the Energy Auditors and support staff during the
Audit/Measurement Phase.
All the key areas of concern were openly discussed and they really helped us to direct our
efforts towards the company goals and objectives.
We would like to mention here that all the recommendations included in this report are
executable at the plant level. Exact quantification and converting these ESOs (Energy Saving
Opportunities) into ECM (Energy-saving measures) would require a detail study, where ever
mentioned. We also would like to state here that we possess all the necessary skills and
infrastructure through our own setup and with our associates, to execute the recommended
projects and help you in achieving end results.
Thanking you once again and wishing you all the success in your “Save Energy Mission”.
Team – Vedant Energy Solutions LLP,
Aurangabad, India
PAGE| 14 www.fosterms.com
D. Methodology used during the energy audit
1) Visit the entire plant to understand the process, the flow of material and flow of
energy.
2) Measure actual energy consumption using standard calibrated equipment and
prepare energy consumption pie chart showing the contribution to each major
process used by the plant. Also, prepare a pie chart showing the contribution of
electrical and thermal energy.
3) Understand % energy consumption for various processes and utilities.
4) Collect historical data on energy consumption versus plant output or material input
which got processed in the same period.
5) Establish specific energy consumption patterns and investigate “Hick ups if any”.
Study and confirm the applicability of criteria followed by the plant to calculate
specific energy consumption.
6) Calculate theoretical specific energy requirements for processes wherever possible,
refer to ideal Industry benchmarks and comment on deviations found if any.
7) Study basic conversion processes and equipment used by physical measurements to
identify major losses if any.
8) Recommend energy saving majors along with possible saving and required budgetary
investments.
Major activities carried out by our team
a) Electrical parameters (kW) measurement on all major feeders and preparing pie chart.
b) Collection and study of historical data on energy and plant Input/Output, wherever
possible.
c) Infrared thermography of all major heat radiating insulated surfaces to know the
condition of Insulation and avoidable heat loss.
d) Flow measurements where ever applicable.
e) Flue gas analysis of exhaust gases of various furnaces to know combustion efficiency,
wherever applicable.
f) Cooling tower and chillers effectiveness analysis.
g) Study of Compressed air use and FAD/Leakage tests on compressors.
www.fosterms.com PAGE|15
E. Summary of Energy Saving Opportunities in the plant
This energy Audit is one of the parts of the energy conservation initiatives taken by the plant
wherein efforts are taken to measure the efficiencies of energy-intensive equipment,
establishing specific energy consumption benchmarks and remedial actions for optimization
of energy costs (Both Fuel and Electricity).
Observations and recommendations are given below.
1. A’Safwah Dairy & Beverages Co. utilises electricity and LPG as a primary energy source
for the production of various dairy and beverages products.
2. Energy Consumption of the PET plant per month is approximately 237935 kWh which
costs approximately 6662 OMR.
3. Average production of the PET plant per month was found to be 103.6 MT per month
(Data provided by the plant).
4. From the historical and statistical data analysis, it has been found that ideally when
there is no production going on in the PET plant, the minimum energy consumed by the
plant is 51115 kWh/month which is approximately 21% of monthly consumption. This
energy consumption is considered to be a fixed energy consumption. This fixed
consumption of electricity amounts to 1431 OMR/month.
5. The linear relation deducted was obtained as “y = 1.8043x + 51115” which indicates the
variable energy consumption as 1.8043 kWh/MT of production and 51115 kWh as fixed
energy consumption.
6. It can be seen that the variable energy consumption remained more or less similar
throughout the year for PET plant. This proves that the production process is already
optimised to the production.
7. SEC Analysis of Dairy section was not done due to unavailability of data.
8. PET Plant production schedule was on low, AC plant and Tower ACs were on partial load
and at times were off after first shift.
A. Transformer Loading
It has been observed that all the transformers are of 2500 kVA capacity. During the audit
phase, it has been found that the transformers were loaded on an average of 20%. Loading
the transformer in the range of 65-75% will save losses occurring in the transformer. The
summary of the losses in the transformers is given below.
( )
PAGE|16 www.fosterms.com
Sr. No. Transformer P total losses (kW)
1 Transformer – 1 1.935
2 Transformer – 2 1.571
3 Transformer – 3 1.375
4 Transformer – 4 1.417
5 Transformer – 5 1.213
6 Transformer – 6 1.28
7 Total 8.791
Though these losses are unavoidable, annual cost impact due to transformer losses is App.
2200 OMR (At the loading measured during audit).
B. Reactive Power Management
Present total APFC panel of 800 kVAr is delivering app. 264.3 kVAr which is not
sufficient to meet the need at present requirement of 864.36 kVAr. By replacing the de-
rated capacitors, the energy savings can be achieved is 318 OMR/annum.
C. PET plant
Major Energy Saving Opportunities in Electrical Section:
Normally the process of energy conservation shall head from the statistical analysis of
Specific Energy Consumption of the plant and to correlate with the energy assessment done
during the audit, hence from the analysis, total potential of Energy Conservation is from two
areas,
a. Optimizing the Fixed Component of Energy and to bring near to the X-Axis (Refer
Detailed Graphs), here the fixed energy costs app. 1431 OMR/Month for PET
plant.
b. If the benchmark is taken to reduce above cost by 15% to 20%, level – 1 target for
energy saving, then energy savings should be 10223 kWh per month.
Our Study/Energy Audit is thus directed towards finding out the gaps in the
operating systems especially fixed costs energy centres i.e. Chillers, Cooling Towers,
Illuminations, Raw Water Pumping.
Energy Saving Opportunities are divided into two segments for all utilities/equipment.
i. Reduction in Specific Energy Consumption close to the design.
ii. Reduction in wastage of energy through losses from insulation, in-effective
practices, design issues etc.
1. York Chilled Water Plant
Present TR loading on the chiller is 25.2 (42% loading). Therefore, the operating cost of the
chiller is 1.3 OMR/hour. Considering average 24 hours of operation per day
www.fosterms.com PAGE|17
a. and 350 days a year with a diversity factor of 66%, reducing the SEC up to 1.5 kW/TR would
provide a savings of 51733 kWh/annum or 1448 OMR/annum.
b. It is recommended to reduce the scaling through the evaporator so as to reduce the
additional flow rate through the evaporator to match with the pump rated flow and enhance
the present ΔT of 1.5°C near design ΔT.
c. The secondary pump efficiency is very poor. The speed of the secondary pump must be
reduced in order to obtain the required flow necessary as per the load. The use of VFD with
PID control in order to reduce the flow according to the load will enable considerable savings
in the secondary pump power consumption.
2. Aoki 1 & 2 – Mould Cooling Chilled Water Plant
a. Present TR loading on the chiller is 9.83. Therefore, the operating cost of the chiller is 0.48
OMR/hour. Considering average 24 hours of operation per day and 350 days a year with a
diversity factor of 66%, reducing the SEC up to 1.5 kW/TR would provide a savings of 13624
kWh/annum or 380 OMR/annum.
3. Aoki 3 Mould Cooling Chilled Water Plant
a. Present TR loading on the chiller is 12.3. Therefore, the operating cost of the chiller is 0.54
OMR/hour. Considering average 24 hours of operation per day and 350 days a year with a
diversity factor of 66%, reducing the SEC up to 1.5 kW/TR would provide a savings of 4091
kWh/annum or 114 OMR/annum.
4. Air Compressor – PET plant
a. Observed specific power consumptions for air compressor 1, 2, 3 & 4 are 0.640, 0.218, 0.251,
0.219 kw/cfm respectively. which is more than 0.18 to 0.21 kW /cfm.
b. Reducing the specific energy consumption of compressor no. 3 and 4 will save energy
consumption by 29350 kWh/annum amounting to 4109 OMR/annum.
D. Dairy Plant
Major Energy Saving Opportunities in Electrical Section:
1. Air Compressor – Dairy Section
a. Comp. no. 1, 2, 5 & 6 is running on 70.63, 93.02, 42.49, 84.26 % loading respectively and their
volumetric efficiencies observed are 78.06, 72.66, 77.61, 82.37 % respectively.
b. Observed specific power consumptions for air compressor 1, 2, 5 & 6 are 0.255, 0.286, 0.271,
0.242 kW/cfm respectively, which is more than a standard value of 0.18 to 0.21 kW/cfm.
c. Reducing the unloading pressure of compressor no. 2 and increasing the % loading time of
compressor no. 5 will help reduce the energy consumption as the specific energy
consumption of compressor no. 2 is greater than compressor no. 5.
PAGE|18 www.fosterms.com
d. The various savings that can be achieved through energy saving opportunities are given in the
below,
Energy Savings Opportunities Savings Savings
Sr. No.
(kWh/annum) (OMR/annum)
1 Reducing SEC up to 0.21 kW/cfm 219475 6145.3
2 Reducing 15% leakages (66.71 cfm) 119643 3350
3 Reducing pressure by 0.8 to 1.0 kg/cm 2 31714 888
4 Total savings 370832 10383.3
2. Ice Bank Chilled Water plant
a. Delivered TR at given loading (found as 37.5%) at the time of audit is 93.75. Therefore, the
operating cost of the chiller is 3 OMR/hour. Considering average 24 hours of operation per
day and 350 days a year with a diversity factor of 66%, reducing the SEC up to 0.88 kW/TR
would provide a savings of 136,875 kWh/annum or 3832.5 OMR/annum.
b. During the low load of chilled water plant, the chiller for the Ice Bank should be run during the
night time for the major of the time, so that the cost effectiveness of CRT tariff can be utilised.
Major Energy Saving Opportunities in Thermal Section:
1. Boiler
a. It has been observed that the excess air % in the flue gas was found to be about 54% which is
on the higher side of the allowable side. The maximum allowable % of excess air for LPG is 10-
15%.
b. It has been observed that the Steam distribution header insulation has been damaged.
Replacement of the insulation is a must as it will save fuel consumption of the boiler.
Sr. no. Description Observations (%) Recommended Values (%)
1 O 2 % 7.7 2-5
2 CO 2 % 8.79 10-13
3 Excess Air % 53.78 10-15
2. Steam Distribution, Feed Water and Condensate System
a. It has been observed that the steam distribution, feed water and condensate system pipelines
were uninsulated which is a sheer wastage of energy. This energy loss can be saved by
insulating the systems. The detailed insulation description has been given in the report.
b. The insulation of the above system will yield an annual LPG savings of 3745 kg which yields a
saving of 472 OMR/annum (assuming cost of LPG as 0.126 OMR/kg).
www.fosterms.com PAGE|19
E. Illumination
a. Annual energy consumption of lighting is estimated at 205,733 kWh and cost as
much as 5760 OMR.
b. We recommend converting all the areas into LED Lighting as well. Expected saving by
conversion of conventional lights into LED is 125066 kWh per annum i.e. 3502 OMR
per annum @ 12 Hours per day and 350 days of operation.
c. It was also observed that in the Injection Mould Shop and other sections all the
lightings were ON without any person present. Adaptation of Occupancy sensors in
the passages, corridors are highly recommended. A good technology of tube lights
with inbuilt occupancy sensors is readily available in the market.
d. Apart from the above, it is very necessary to improve awareness among the
employees so that they adopt good habits to put lights off when they leave the work
area. It is observed at quite a few locations including offices. Refer Photographs in
the report.
e. Awareness campaigns, slogans, posters on every switchboard, switch and light
identification/tagging is necessary and shall be initiated at the plant level.
F. Specific Energy Consumption (SEC) of Blow Moulding Machines – PET plant
a. It has been found that there is a deviation of 20% and 34% for the blow mould
machines Aoki – 2 and Aoki – 3 respectively when compared with Aoki – 1.
b. There is a deviation in the SEC for the same type of machines because of the
operational parameters of the utilities associated with them.
c. During the part load operation of the chillers, the power consumption becomes
erratic because of which the there is a difference in the SEC between the machines.
d. As the utility infrastructure is already installed, it is advised to install individual
energy meters along with Btu meters. Btu meters sense the total heat requirement
and accordingly can be used to find the exact SEC for the machine.
e. The control on the different utilities can be achieved using IoT based energy
monitoring system which will enable a greater savings during the part load
operation.
f. SOPs should be developed which must incorporate energy performance standards.
G. Al Najd Agricultural Development Co.
An energy audit was conducted at Hanfeet Farm which included the assessment of
submersible pumps installed for the purpose of irrigation using sprinkler system.
a. It was observed that the pump efficiency varied between the three types of
pumps which were assessed.
PAGE|20 www.fosterms.com
b. Also, there was no provision to measure the suction pressure as well as water
level below the ground level.
c. It is advised to dig a dummy borewell so that the measure the water level
below the ground and monitor the water level throughout the year.
d. Monitoring the water level will enable the personnel to understand the water
level characteristics of the area which will help in determining the head at
which the pump is operating.
e. A detailed analysis of the pumping system including the determination of
system resistance curve must be found out and it should be plotted on the
pump curve provided by the pump manufacturer.
f. According to the head, the personnel can compare the difference between
actual and ideal power comparison.
g. It is advised to install an IoT based Energy monitoring system which includes
water level indicator and must be monitored accordingly.
h. It is also advised to install PID control for pump flow rate maintenance during
as per the head available so that the pump operates near its Best Efficiency
Point.
i. Also, wherever possible, paraffin filled pressure gauges must be installed so as
to determine any additional head losses occurring in the water distribution
system.
H. IoT based Energy Monitoring System
The IoT based Energy monitoring system will enable the plant to monitor the actual
energy consumption of different utilities and will enable it to take necessary actions to reduce
the unnecessary energy wastage and consumption and also reduce the specific energy
consumption of the product. The system architecture for an IoT based energy monitoring
system as an example is shown below.
The chillers will include a PLC Control panel which will get the input of temperature of
pressures and temperatures located at various locations and a WiFi module will be connected
to the PLC controller which will transfer the data to the computer. The user needs to enter
the production details daily and then the computer software will directly give the specific
energy consumption of the particular utility or the section considered in the IoT.
www.fosterms.com PAGE|21
Figure a. IoT based System - Example
This system then needs to be monitored regularly and properly and the necessary data must be captured
from the IoT and accordingly, actions must be taken for an effective operation.
Recommendations:
a. It is advised to install an IoT based energy monitoring system for the compressors and chillers in the
plant because of their comparatively higher energy consumption.
b. The monitoring of this system will be helpful in reducing the drastic variations found in the specific
energy consumption of the plant.
c. An energy meter based system can be installed on individual Injection Moulding Machines to monitor
the energy consumption per product required which then must be compared with the rated energy
consumption of the machine. This will help in the improvement of the production process and reduce
the embodied energy of the product.
I. Alternate Energy Source: Solar Photovoltaic
The cost reflections from the Electricity board are not predictable in the region. So, it is highly
recommended to go for alternate energy source such as solar photovoltaic energy. The Solar PV technology is
most preferable for the plant because of the availability of Irradiation at the location.
A feasibility study for 1000 kWp solar power plant along with the estimated costs is presented in
detail. The estimation is determined on the basis of availability of roof area. The 1000 kWp solar power plant
will generate about 1.522 million kWh of energy per year. For details, please refer the detailed report.
PAGE|22 www.fosterms.com
Total Scope for Savings in different sections
Sr. Section Energy Saving Opportunities Energy Loss Cost due to
No. (kWh/annum*) Energy loss
(OMR/annum)
A PET Plant
1 York Chilled Water Reducing SEC up to 1.5 51733 1488
Plant kW/TR
Increasing Secondary Pump 12862 360
efficiency up to 50%
2 Aoki 1 & 2 - Mould Reducing up to 1.5 kW/TR 13624 381
Cooling Chilled Increasing Primary Pump 15523 435
Water Plant efficiency up to 50%
3 Aoki 3 - Mould Reducing SEC up to 1.5 4091 115
Cooling Chilled kW/TR
Water Plant Increasing Primary Pump 14066 394
efficiency up to 50%
4 Air Compressor - PET Reducing SEC up to 0.21 29350 822
Section** kW/cfm
B Dairy Plant
1 Ice Bank Chilled Reducing SEC up to 0.88 129937 3638
Water plant kW/TR
Increasing Primary Pump 51168 1433
efficiency up to 50%
2 Air Compressor - Reducing SEC up to 0.21 219475 6145
Dairy Section** kW/cfm
Reducing 15% leakages 119643 3350
(66.71 cfm)
Reducing pressure by 0.8 to 31714 888
2
1.0 kg/cm
3 Illumination Replacing existing lightings 125066 3502
with LEDs
4 Steam Distribution Insulating the steam 3745 kg of LPG 472
Insulation*** distribution system with 4"
rock-wool insulation
C Total
* @24 hours and 350 days of operation with 66% diversity factor
** Diversity factor consider here is based on %loading.
*** Energy savings will be achieved in fuel consumption of LPG (kg/year).
www.fosterms.com PAGE|23
1. ENERGY DETAILS OF THE PLANT
1.1 Background and Process Description
A’Safwah Dairy is the only largest vertically integrated dairy company in Sultanate of Oman. The
company has remarkable goodwill, producing premium quality fresh milk, dairy products and juices
which are sold both in Oman and overseas, under the brand name A'Safwah Milk and Dairy products
and A'Safwah Beverages.
The major products of the dairy plant include Fresh Milk, Fresh Laban, Fresh Laban Drink, Fresh
Yoghurt, Fresh Juices, UHT Juices and UHT Milk with a variety of sizes available. The A’Safwah Dairy
plant consists majorly of two sections viz. Dairy plant and PET plant. The PET plant is used for the
preparation of bottles and bottle caps of various sizes using various blow moulding machines and
stretch injection moulding machines respectively. In the Dairy plant, the process of production of
various milk products and drinks is carried out and then it is filled in the manufactured bottles. The
detailed flow process diagrams for the products mentioned above is given in the Annexure.
1.2 Production
The production of the plants includes manufacturing of different types of drinks and juices
including different types of bottles and bags in their PET plant. The production of bottles of the plant
from July-17 to June-18 is illustrated in the chart below and is found to be on an average of 88.54
MT. The plant also produced caps for the bottles. The production for the caps was made during the
months of Jan-17 to Jun-17 and Jan-18 to Jun-18. The production of caps averaged out to be 17.87
MT.
Production vs. Month (Bottles and Bags)
160.0
140.0
Production (kg) x 10 3 120.0
100.0
80.0
60.0
40.0
20.0
0.0
Month
PAGE|24 www.fosterms.com
Production vs. Month (Caps)
30
Production (kg) x 10 3 20
25
15
10
0 5
Jan-17 Feb-17 Mar-17 Apr-17 May-17 Jun-17 Jul-17 Aug-17 Sep-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18
Month
Figure 1. Production vs. Month (Bottles, Bags and Caps) chart
1.3 Electrical Infrastructure and Consumption
A’Safwah Dairy receives power at 11 KV as the main input and is given to the plant through 7
different transformers. These transformers feed electricity to the different parts of the plant. The
plant consists of 2 sections viz. Dairy and PET. During the audit phase, it was observed that the
Transformers 1, 2, 3 and 6 were in connection with the Dairy section and the Transformers 4 and 5
were in connection with the PET plant.
The transformer-wise pie chart along with individual plant pie chart is given below.
Transformer-wise Pie Chart
13%
Transformer 1
25%
8% Transformer 2
Transformer 3
Transformer 4
20%
Transformer 5
18%
Transformer 6
16%
Figure 2. Pie Chart – Transformer wise (kW)
www.fosterms.com PAGE|25
PET Plant - Pie Chart
3%
8%
Utilities
47% Machines
Others
42% Lighting
Figure 3. Pie Chart – PET plant
Dairy Plant - Pie chart
Utilities
42% Waste Water
45%
APV process
Lighting
Others
4% 7%
2%
Figure 4. Pie Chart – Dairy Plant
From the above graphs, it can be found that the utilities in the plant i.e. chillers and
compressors contributed about 47% and 42% in the energy consumption of PET and Dairy
plant respectively. The lighting is the next common energy consumption area consuming 3%
and 4% in PET and Dairy plant respectively.
1.4 Fuel Consumption
A’Safwah Dairy also uses LPG as a fuel for firing its boiler. The boiler was used for various
processes to be carried out in the manufacturing of milk and juices. The fuel consumption per
month is given in the following table.
PAGE|26 www.fosterms.com
Table 1. LPG Consumption from Jan-18 to May-18
3
Sr. No. Month Consumption (m )
1 Jan-18 152.88
2 Feb-18 141.57
3 Mar-18 175.37
4 Apr-18 146.9
5 May-18 168.22
1.5 Specific Energy Consumption – PET plant
Based on the historical data, a relation was developed between the electrical energy consumption
and the production of various products in the PET plant. The relation is called as Specific Energy
Consumption which defines the energy consumption per kg of product produced. Also, a deduction
was made between the best SEC and the worst SEC.
Table 2. Specific Energy Consumption – PET plant
Electrical Production
SEC
Sr. No. Month Consumption (Metric (kWh/kg) % Deviation from Energy Lost
the Best SEC
(kWh)
(kWh) Ton)
1 Apr-17 207153 88.7 2.34 11.37 23548.92
2 May-17 258661 118.6 2.18 5.09 13165.58
3 Jun-17 330899 150.2 2.20 6.04 19993.34
4 Jul-17 266491 123.2 2.16 4.31 11473.84
5 Aug-17 223761 108.1 2.07 0.00 0
6 Sep-17 218973 90.9 2.41 14.07 30815.05
7 Oct-17 261256 112.9 2.31 10.55 27559.27
8 Nov-17 240392 105.3 2.28 9.33 22426.84
9 Dec-17 205510 81.3 2.53 18.11 37223.51
10 Jan-18 194632 78.6 2.48 16.41 31934.36
11 Feb-18 195794 82.3 2.38 12.99 25437.57
12 Mar-18 250701 107.4 2.33 11.32 28388.96
13 Apr-18 238933 99.2 2.41 14.06 33594.51
14 Total Energy Lost for the year (kWh) 305,561.75
From the above table, it can be deducted that the Specific Energy Consumption of the PET plant was
in less control and the % deviation of SEC from the best SEC was up to 18% at most. It has been also
observed that due to the deviation in the energy consumption, there was a total energy loss of app.
305,560 kWh for the year 2017-18.
www.fosterms.com PAGE|27
Specific Energy Consumption - PET Plant
350 y = 1803.4x + 51115
Electricity Consumption (kWh x 10 3 ) 250
300
200
150
100
50
0
60 70 80 90 100 110 120 130 140 150 160
Production (MT)
Figure 5. Specific Energy Consumption – PET plant
From the statistical analysis in the above table and graph, it can be deduced that ideally when
there is no production going on in the PET plant, the minimum energy consumed by the plant
is 51115 kWh/month. This energy consumption is considered to be a constant energy
consumption. This fixed consumption of electricity amounts to 7156 OMR/month.
PAGE|28 www.fosterms.com
2. ELECTRICAL POWER MEASUREMENT & ANALYSIS OF DISTRIBUTION SYSTEM
2.1 Electrical Power Distribution and Capacitor Watt Loss
The electrical power measurement was carried out at the incomer of every transformer viz. Transformers 1, 2, 3, 4, 5 and 6. It was found that all the
transformers were operating at a power factor below 0.9. This reduction in power factor is because of the deration of capacitors/APFC panels with time.
The detailed watt loss of different APFC panels is given in the below table.
Table 3. Details of Power Measurement of the Electrical Distribution system for different transformers of the plant
SR. FEEDER U RMS (V) A RMS (A) A THD (%) U THD (%) PF kW kVA kVAr
NO. NAME R Y B R Y B AVG AVG AVG AVG MAX AVG MAX AVG MAX
1 TR-1 411.75 413.99 415.01 645.4 672.36 667.88 2.41 0.5867 0.803 380.85 423.81 474.46 566.28 280.06 379.31
2 TR-2 414.14 417.14 417.62 491.34 447.83 494.79 1.61 0.6967 0.786 270.62 281.72 344.44 361.54 211.85 233.56
3 TR-3 408.32 410.7 411.8 352.41 337.57 356.51 3.19 0.7167 0.909 223.64 239.77 246.93 282.83 98.09 154.88
4 TR-4 415.28 418.56 418.31 398.77 351.61 378.34 3.18 0.7433 0.908 246.06 318.94 270.96 346.2 111.45 146.86
5 TR-5 416.54 419.72 419.38 180.56 144.22 157.81 30.27 0.71 0.856 99.79 103.67 116.59 121.54 49.4 53.37
6 TR-6 407.94 410.41 411.17 248.78 261.89 270.09 4.53 0.6767 0.778 141.77 222.64 182.11 323.57 113.49 235.27
Table 4. Watt Loss of Capacitors
APFC capacity Max. Delivered Watt consumed Allowable Watt Cost/unit Savings/year
Sr. No. Transformer Difference
(kVAr) (kVAr) (kW) (kW) (Rs.) (OMR)
1 TR-1 200 41.91 0.962 0.020955 0.941045 5 231.56
2 TR-2 200 33.37 0.213 0.016685 0.196315 5 48.31
3 TR-3 200 76.36 0.174 0.03818 0.13582 5 33.42
4 TR-4 200 112.63 0.077 0.056315 0.020685 5 5.09
www.fosterms.com PAGE|29
2. ELECTRICAL POWER MEASUREMENT & ANALYSIS OF DISTRIBUTION SYSTEM
2.1 Electrical Power Distribution and Capacitor Watt Loss
The electrical power measurement was carried out at the incomer of every transformer viz. Transformers 1, 2, 3, 4, 5 and 6. It was found that all the
transformers were operating at a power factor below 0.9. This reduction in power factor is because of the deration of capacitors/APFC panels with time.
The detailed watt loss of different APFC panels is given in the below table.
Table 3. Details of Power Measurement of the Electrical Distribution system for different transformers of the plant
SR. FEEDER U RMS (V) A RMS (A) A THD (%) U THD (%) PF kW kVA kVAr
NO. NAME R Y B R Y B AVG AVG AVG AVG MAX AVG MAX AVG MAX
1 TR-1 411.75 413.99 415.01 645.4 672.36 667.88 2.41 0.5867 0.803 380.85 423.81 474.46 566.28 280.06 379.31
2 TR-2 414.14 417.14 417.62 491.34 447.83 494.79 1.61 0.6967 0.786 270.62 281.72 344.44 361.54 211.85 233.56
3 TR-3 408.32 410.7 411.8 352.41 337.57 356.51 3.19 0.7167 0.909 223.64 239.77 246.93 282.83 98.09 154.88
4 TR-4 415.28 418.56 418.31 398.77 351.61 378.34 3.18 0.7433 0.908 246.06 318.94 270.96 346.2 111.45 146.86
5 TR-5 416.54 419.72 419.38 180.56 144.22 157.81 30.27 0.71 0.856 99.79 103.67 116.59 121.54 49.4 53.37
6 TR-6 407.94 410.41 411.17 248.78 261.89 270.09 4.53 0.6767 0.778 141.77 222.64 182.11 323.57 113.49 235.27
Table 4. Watt Loss of Capacitors
APFC capacity Max. Delivered Watt consumed Allowable Watt Cost/unit Savings/year
Sr. No. Transformer Difference
(kVAr) (kVAr) (kW) (kW) (Rs.) (OMR)
1 TR-1 200 41.91 0.962 0.020955 0.941045 5 231.56
2 TR-2 200 33.37 0.213 0.016685 0.196315 5 48.31
3 TR-3 200 76.36 0.174 0.03818 0.13582 5 33.42
4 TR-4 200 112.63 0.077 0.056315 0.020685 5 5.09
www.fosterms.com PAGE|29
Observations:
1. Average loading on the transformers during the measurement period is observed at
380.85, 270.62, 223.64, 246.02, 99.8 and 141.77 kW with a maximum load of 423.81,
281.72, 239.77, 318.94, 103.67 and 224.64 kW for the transformers no. 1, 2, 3, 4, 5
and 6 respectively.
2. Also, it is seen that there is an average minimum reactive power requirement of 100
kVAr during normal running conditions except for Transformer 5.
3. Present total APFC panel of 800 kVAr for Transformers 1 to 4 is delivering app. 264
kVAr which is not sufficient to meet the need at present by app. 576 kVAr.
PAGE|30 www.fosterms.com
3. ENERGY PERFORMANCE ASSESSMENT OF ELECTRICAL UTILITIES
3.1 Ice Bank Chilled Water Plant – Dairy Plant
3.1.1 Chiller
Table 5. Energy Performance Assessment – Ice Bank Chilled Water Plant
Description Observations
Status From old ice bank system, chilled water compressor
2 and 3 are on loading condition and compressor 1
is observed in standby mode. and for new ice bank
system, out of 5 compressors, only compressor no.
3 is on line.
Make SABROE
Model Screw compressor, Ammonia chiller
Type SAB 128 HF
Refrigerant Ammonia (NH 3)
3
Volume, m /hr 456/547 for each chiller
Maximum Allowable pressure, bar 26
Yr. of installation 2005
Voltage 415
Phase 3
Rated Frequency 50 Hz
Chilled water inlet temp, °C 6.4
Chilled water outlet temp, °C 0.1
Chilled water ΔT, °C 6.3
3
Existing Chilled water flow, m /hr 45
Line size 4”
3
Flow observed, m /hr 45
Velocity, m/s 1.46
Signal UP 602: DN 602: Q 68 R
Existing Chilled water heat load, kcal 2,83,000 ( 93.75 TR)
Rated plant capacity, kcal 7,56,800 (250 TR)
Old IBT Compressor 1, 2, 3 loading observed, % 0 %, 100%, 60 % and 55 %
and New IBT compressor 3 is on load
Observed power, kW 106.38
Specific power consumption, kW/TR 1.13
www.fosterms.com PAGE|31
3.1.1 Circulation Pumps
Table 6. Energy Performance Assessment – Chilled Water Circulation Pumps
Description Observations
Chilled water circulation pump no.1, 2, 3 & 4
Pump status Observed CHSW pump no.1, 2 & 4 are on and 3 is in
shut off condition
Pump flow observed through, Common discharge header,4”
Make Grundfoss
Type Centrifugal love joy coupled
Size NA
Head, m 39
3
3
Capacity, m /hr 95.2 m /hr for pump no. 1,
3
31 m /hr for 3 pumps i.e. 2, 3 & 4
RPM 2900
Pump no. 1 - 20 HP/75 kW
HP
Pump no. 2, 3 & 4 – 5 HP/3.7 kW
Observations
Observed flow parameters
Pipe perimeter 360 mm
MOC of pipe MS
Transducer Method Z method
Transducer Spacing, mm 54 mm
3
Flow observed, m /hr 45
Velocity, m/s 1.46
Signal UP 602 : DN 602: Q 68 R
Time 03:30 pm / 19.06.2018
3
Observed Flow, m /hr 45
10.23 kW, 3.51 kW, 3.59 kW;
Observed Motor Power, kW
Total power- 17.33 kW
2
Head, kg/cm (g) 3.75
Motor Loading % 60.69 %, 84.42 %, 86.35 % respectively
Hydraulic power generated, kW 4.598
Shaft power, kW 15.42
Pump Efficiency, % 29.81%
PAGE|32 www.fosterms.com
3.1.2 Observations and Recommendations
a. It is observed that existing specific energy consumption is 1.13 kW/TR. Facility dept. try to
maintain it up to 0.88 kW/TR with the help of regular preventive maintenance of condensing
unit, chilled water side descaling and proper cleaning of IBT tanks on scheduled shutdown
period.
b. Presently load on the chilled water plant (IBT) observed is 37.5 %. Current ΔT is 6.3°.
Increasing the evaporator set temperature as per the load and rated design ΔT will reduce
the energy consumption of the chiller. A 1°C rise in evaporator temperature can help to save
almost 3 % on power consumption.
c. It is recommended to install air vent valves at a top most point in the plant on Chilled water
supply header in the plant to avoid air logging in the circuit.
d. Observed recirculating chilled water colour is towards reddish. Needs to check iron content in
the chilled water. Accordingly, start the proper chemical treatment to control iron oxide
below 3 ppm in the recirculation chilled water. This definitely helps in preventing corrosion in
the chilled water system.
3.2 York Chilled Water Plant – PET Plant
3.2.1 Energy Performance Assessment – York Chilled Water Plant
Table 7. Energy Performance Assessment – York Chilled Water Plant
Description Observations
Status Aoki m/c no. 1, 2 & 3 blow operation and oil cooling chilling
water plant are on.
Make York
Model YCAL0287EC50XCBDB
Type Hermetically sealed scroll compressor units
Refrigerant R-22
Capacity 60 TR (12 TR-5 compressor units)
Yr. of installation 10 - 2005
Voltage 415
Phase 3
Rated Frequency 50 Hz
Observations – Chiller
Chilled water inlet temp, °C 20
Chilled water outlet temp °C 18.5
Chilled water ΔT, °C 1.5
3
Existing Chilled water flow, m /hr 50.85
Line size 3”
3
Flow observed, m /hr 50.85
Velocity, m/s 3.18
Signal UP 842: DN 841: Q 84 R
Existing Chilled water heat load, kCal 76275 Kcal (25.22 TR)
Observed power, kW 47.20
Specific power consumption, kW/TR 1.87
Chilled water primary circulation Pump Aoki m/c no. 1, 2 & 3 blow operation and oil cooling chilling
water plant are on.
Pump status Primary chilled water circulation pump no in ON condition
Pump flow observed through Discharge header, 3”
Make SPP pump
Type Centrifugal love joy coupled
Size NA
Head, m 27
3
Capacity, m /hr 48.60
RPM 1450
HP Pump no. 1 - 10 HP / 7.5 kW
Observations – Primary Chilled Water Pump
Observed flow parameters
Line size, inch 3”
Pipe perimeter 280 mm
MOC of pipe MS
Transducer Method Z method
Transducer Spacing, mm 17
3
Flow observed, m /hr 50.85
Velocity, m/s 3.18
Signal UP 842: DN 841: Q 84 R
Time 12:30 pm / 20.06.2018
3
Observed Flow, m /hr 50.85
Observed Motor Power, kW 7.07
2
Head, kg/cm (g) 1.60
Motor Loading % 84.84 %
Hydraulic power generated, kW 2.217
Shaft power, kW 6.36
Pump Efficiency, % 34.85 %
Chilled water secondary circulation Pump Aoki m/c no. 1, 2 & 3 blow operation and oil cooling chilling
water plant are on.
Pump status Secondary chilled water circulation pump is in ON condition
Pump flow observed through, Discharge header,3”
Make SPP pump
Type Centrifugal love joy coupled
Size 65-32/329
Head, m 37
3
Capacity, m /hr 48
RPM 1450
HP Pump no. 1 - 15 HP / 11 kW
Observations – Secondary Chilled Water Pump
Observed flow parameters,
Line size, inch 3”
Pipe perimeter 280 mm
MOC of pipe MS
Transducer Method Z method
Transducer Spacing, mm 17
3
Flow observed, m /hr 26.90
Velocity 1.68
Signal UP 860: DN 858: Q 94 R
Time 02:30 pm / 20.06.2018
3
Observed Flow, m /hr 26.90
Observed Motor Power, kW 7.88
2
Head, kg/cm (g) 1.60
Motor Loading % 64.47 %
Hydraulic power generated, kW 1.172
Shaft power, kW 7.09
Pump Efficiency, % 16.53 %
www.fosterms.com PAGE|34
3.2.2 Observations and Recommendations
3
a. Observed ΔT is 1.5 °C. The flow through the primary pump is observed to be 50.92m /hr
which is greater than the rated flow of the pump. It is recommended to reduce the scaling
through the evaporator if present so as to reduce the flow rate through the evaporator to
match with the pump rated flow.
b. The observed loading % on the chiller is 42%. The secondary pump efficiency is very poor.
The speed of the secondary pump must be reduced in order to obtain the required flow
necessary as per the load. The use of VFD in order to reduce the flow according to the load
will enable considerable savings in the secondary pump power consumption.
c. It is recommended to install air vent valves at topmost point in the plant on Chilled water
supply header in the plant to avoid air logging in the circuit.
d. Observed recirculating chilled water colour is towards reddish. Needs to check iron content in
the chilled water. Accordingly, start the proper chemical treatment to control iron oxide
below 3 ppm in the recirculation chilled water. This definitely helps in preventing corrosion in
the chilled water system.
e. Its observed that existing specific energy consumption is 1.87 kW/TR. Facility dept. try to
maintain it up to 1.4 kW/TR with the help of regular preventive maintenance of condensing
unit, chilled water side descaling and proper cleaning of the internal tank on scheduled
shutdown period. Also, need commissioning report of chiller plant to correlate its existing
performance.
3.3 Aoki 1 & 2 Mould Cooling Chilled Water Plant – PET Plant
3.3.1 Energy Performance Assessment – Aoki 1 & 2 Mould Chilled Water Plant
Table 8. Energy Performance Assessment – Aoki 1 & 2 Mould Cooling Chilled Water Plant
Description Observations
Status Aoki m/c no. 1/2 Mould cooling chilling water plant is
on. Presently Aoki m/c no.2 is in running condition.
Make Osaka Reiken Co Ltd, Japan.
Model DC-20-W
Type Hermetically sealed compressor units
Refrigerant R-22
Capacity NA
Yr. of installation 10 - 2005
Voltage 415
Phase 3
Rated Frequency 50 Hz
Observations – Chiller
Chilled water inlet temp, °C 18
Chilled water outlet temp, °C 16
Chilled water ΔT, °C 2.0
3
Existing Chilled water flow, m /hr 14.87 (Aoki m/c no. 2 is in running )
Line size 3”
3
Flow observed, m /hr 14.87
Velocity, m/s 0.91
Signal UP 808: DN 808: Q 91 R
Existing Chilled water heat load, kCal 29740 (9.83 TR)
Observed power, kW 17.21
Specific power consumption, kW/TR 1.75
Chilled water circulation Pumps Aoki m/c no. 1/2 Mould cooling chilling water plant is
on. Presently chilled water is a supply for Aoki m/c no.
2 Mould cooling purpose.
Pump status Chilled water circulation pump no in ON condition
Pump flow observed through, Common discharge header,3”
Make Osaka reiken
Type Centrifugal love joy coupled
Size NA
Head, m NA
3
Capacity, m /hr NA
RPM 2900
HP Pump no. 1 - 15 HP / 11 kW
Observations – Chiller Pump
Observed flow parameters
Pipe perimeter, mm 280
MOC of pipe MS
Transducer Method Z method
Transducer Spacing, mm 17
3
Flow observed, m /hr 14.87
Velocity, m/s 0.91
Signal UP 808: DN 808: Q 91 R
Time 11:30 pm / 20.06.2018
3
Observed Flow, m /hr 14.87 (Aoki m/c no. 2 is in running )
Observed Motor Power, kW 9.5
2
Head, kg/cm (g) 3.50
Motor Loading % 77.97 %
Hydraulic power generated, kW 1.418
Shaft power, kW 8.55
Pump Efficiency, % 16.58 %
3.3.2 Observations and Recommendations
a. Observed load on the chilled water plant is 50 %. The chiller is in operation with two similar machines.
When only a single machine is in operation, half of the rated flow is required. A VFD with PID control
for two flow requirements according to the machine requirement will allow considerable savings in
the primary pump and chiller as well.
b. It is recommended to install air vent valves at topmost point in the plant on Chilled water supply
header in the plant to avoid air logging in the circuit.
c. Observed recirculating chilled water colour is towards reddish. Needs to check iron content in the
chilled water. Accordingly, start the proper chemical treatment to control iron oxide below 3 ppm in
the recirculation chilled water. This definitely helps in preventing corrosion in the chilled water
system.
d. Its observed that existing specific energy consumption is 1.75 kW/TR. Facility dept. try to maintain it
up to 1.4 kW/TR with the help of regular preventive maintenance of condensing unit, chilled water
side descaling and proper cleaning of the internal tank on scheduled shutdown period. Also, need
commissioning report of chiller plant to correlate its existing performance.
www.fosterms.com Page 36
3.4 Aoki 3 Mould Cooling Chilled Water Plant – PET Plant
3.4.1 Energy Performance Assessment – Aoki 3 Mould Cooling Chilled Water Plant
Table 9. Energy Performance Assessment – Aoki 3 Mould Cooling Chilled Water Plant
Description Observations
Status Aoki m/c no. 3 Mould cooling chilling water plant is
on. Presently Aoki m/c no.3 is in running condition.
Make Osaka Reiken Co Ltd, Japan
Model DC-20-W
Type Hermetically sealed compressor units
Refrigerant R-22
Capacity NA
Yr. of installation 10 - 2005
Voltage 415
Phase 3
Rated Frequency 50 Hz
Observations
Chilled water inlet temp °C 17
Chilled water outlet temp °C 19.2
Chilled water ΔT, °C 2.2
3
Existing Chilled water flow, m /hr 16.91
Line size 2”, PVC
3
Flow observed, m /hr 16.91
Velocity, m/s 1.39
Signal UP 838: DN 839: Q 92 R
Existing Chilled water heat load, kCal 37202 Kcal (12.30 TR)
Observed power, kW 19.21
Specific power consumption, kW/TR 1.56
Chilled water circulation Pumps Aoki m/c no. 3 Mould cooling chilling water plant is
on. Presently chilled water is a supply for Aoki m/c
no.3 Mould cooling purpose.
Pump status Chilled water circulation pump no in ON condition
Pump flow observed through, Common discharge header,2”
Make Osaka reiken
Type Centrifugal love joy coupled
Size NA
Head NA
Capacity NA
RPM 2900
HP Pump no. 1 - 15 HP / 11 Kw
Observations
Observed flow parameters
Pipe perimeter, mm 190
MOC of pipe MS
Transducer Method Z method
Transducer Spacing, mm 5
3
Flow observed, m /hr 16.91
Velocity, m/s 1.39
Signal UP 838: DN 839: Q 92 R
Time 12:30 pm / 20.06.2018
3
Observed Flow, m /hr 16.91 (Aoki m/c no. 3 is in running )
Observed Motor Power, kW 10.1
2
Head, kg/cm (g) 2.75
Motor Loading % 82.63 %
Hydraulic power generated, kW 1.267
Shaft power, kW 9.09
Pump Efficiency, % 13.93 %
3.4.2 Observations and Recommendations
b. It is recommended to install air vent valves at a top most point in the plant on Chilled
water supply header in the plant to avoid air logging in the circuit.
Observed recirculating chilled water colour is towards reddish. Needs to check iron content in the
chilled water. Accordingly, start the proper chemical treatment to
a. control iron oxide below 3 ppm in the recirculation chilled water. This definitely helps
in preventing corrosion in the chilled water system.
b. Its observed that existing specific energy consumption is 1.56 kW/TR. Facility dept. try
to maintain it up to 1.4 kW/TR with the help of regular preventive maintenance of
condensing unit, chilled water side descaling and proper cleaning of the internal tank
on scheduled shutdown period. Also, need commissioning report of chiller plant to
correlate its existing performance.
3.5 Air Compressor – Dairy Plant
Photo 1. Air Compressor – Dairy Section
www.fosterms.com PAGE|38
3.5.1 Energy Performance Assessment – Air Compressors – Dairy Section
Table 10. Energy Performance Assessment – Air Compressors – Dairy Section
Air Air Air Air
Description Compressor Compressor no. Compressor Compressor
no. 1 2 no. 5 no. 6
Make Atlas Copco Atlas Copco Atlas Copco Atlas Copco
Type / Model ZT 37 FF GA 30 FF ZT 55 FF ZT 55 FF
Mfg. year 2005 2005 2013 2015
Capacity, cfm 195.6 185.3 281 281
Max. inlet temp., °C 45 45 45 45
Motor, kW 37 30 55 55
Rated Dis. Pressure, bar 8.4 9.8 8.35 8.35
Serial No. NA NA APF 179972 APF 204596
Observations
Working pressure, kg/cm² (g) 7.8 7.8 7.9 7.8
Loading Pressure, kg/cm² (g) 7.7 7.7 7.7 7.7
Unloading Pressure, kg/cm² (g) 8.1 8.5 8.2 8.2
Loading Hours, hr 42514 hr 63366 hr 18967 hr 16375 hr
Running Hours, hr 60190 hr 68118 hr 44639 hr 19435 hr
Unloading Hours, hr 17676 hr 4752 hr 25672 hr 3060 hr
Unloading, % 29.37 % 6.98% 57.51% 15.74%
Loading, % 70.63% 93.02% 42.49% 84.26%
Ambient Air Temp, °C 35 35 35 35
Discharge Air Temp, °C 83 82 82 83
Power taken, kW 39 38.5 59 56
3
Receiver capacity, m /hr 1.5 1.5 1.5 1.5
Connected pipe dia, mm 40 40 50 50
Connected pipe length, mtr 16 18 16 16
Connected pipe volume, m 3 0.02 0.023 0.0314 0.0314
Connected pipe dia, mm 100.00 0.00 100.00 100.00
Connected pipe length, mtr 5 0 5 5
Connected pipe volume, m 3 0.039 0.00 0.039 0.039
Connected pipe dia, mm 0.00 0.00 40 40
Connected pipe length, mtr 0.00 0.00 10 10
Connected pipe volume, m 3 0.000 0.000 0.013 0.013
The total volume of the receiver 1.559 1.523 1.5707 1.5707
with the pipeline, m 3
Pump up time, min 2.31 2.7 1.66 1.56
Temp correction factor 0.865 0.868 0.87 0.87
Free Air Delivery in cfm 152.68 134.64 218.09 231.46
Volumetric Efficiency,% 78.06 % 72.66 % 77.61 % 82.37 %
Specific Consumption in kW/cfm 0.255 0.286 0.271 0.242
During system leakage quantification test Air compressor no. 5 and 6 are taken online
Avg. Load time in Min 0.57 min
Avg. Unload time in Min 1.34 min
System Percentage Leakage 29.84 %
System Leakage Quantity in CFM 134.14 cfm (Air Compressor 5 & 6 are on full load during system
leakage quantification test)
Energy Loss due to Air Leakage 34.33 kW
3.5.2 Observations and Recommendations
a. Comp. no. 1, 2, 5 & 6 is running on 70.63, 93.02, 42.49, 84.26 % loading respectively and their
volumetric efficiencies observed are 78.06, 72.66, 77.61, 82.37 % respectively.
b. To increase volumetric efficiency up to 88 to 92 %, facility dept. should check suction filter assembly
for a choke if any.
c. Observed specific power consumptions for air compressor 1, 2, 5 & 6 are 0.255, 0.286, 0.271, 0.242
kW/cfm respectively, which is more than a standard value of 0.18 to 0.21 kW/cfm.
d. It has also been observed that the unloading pressure of compressor no. 2 is 8.5 bar. Because of this,
the unloading hours of the compressor is very low and compressor no. 5 is unloaded 57% of the time.
Reducing the unloading pressure of compressor no. 2 and increasing the % loading time of
compressor no. 5 will help reduce the energy consumption as the specific energy consumption of
compressor no. 2 is greater than compressor no. 5.
e. The temperature of discharge air is observed to be above 80°C. For better and consistent
performance of air compressor, kindly give proper attention towards the preventive maintenance of
compressor units includes proper overhauling of the unit, regular oil replacement, cleaning of suction
filters, cleaning of radiator assembly to avoid excess specific power consumption during running
condition.
f. Typical 100-psig specific power at full load is approximately 18 kW/100 cfm to 21 kW/100 cfm.
Variable-displacement or variable-speed capacity control is the added benefit for further
improvement in part-load efficiency.
g. for air compressor no. 1,
( )
h. for air compressor no. 2,
( )
i. for air compressor no. 5,
( )
j. for air compressor no. 5,
PAGE|40 www.fosterms.com
( )
Always try to achieve the specific power consumption up to above bench mark consumption.
k. Observed system percentage leakage 29.84 %, i.e. 134.14 cfm. The cost of compressed air
leakage inside the plant is
l. By adopting proper leak detection programme with the replacement of existing damaged
quick release fittings, PVC pipe and faulty FRL units in the plant, we definitely able to save
up to 15% leakages i.e. 66.71 cfm from the present one.
m. Presently it’s necessary to isolate high and low-pressure machines. For Dairy plants,
requirements of compressed air are as follows,
i. Compressed air, used for pneumatic tools, etc. should be free from solid particles and
as dry as possible. The supply pressure should be approximately 600 kPa (6 bar).
ii. Compressed air which does not come into contact with the product, used for the
control of instruments and a source of power to active pneumatic components and
valves etc. must be clean, dry, and preferably oil-free which supply at a pressure
between 500 and 600 kPa (5 – 6 bar).
iii. Compressed air which comes into direct contact with the product should be clean, oil-
free, dry, odourless and practically sterile. Such quality of air is used in relatively small
quantity. The supply pressure should be between 200 and 300 kPa (2-3 bar).
2
As per the feedback from facility dept., minimum 6.0 kg/cm (g) pressure is required at the plant level.
2
Hence it’s clear that we can modulate generated compressed air pressure in 6.5 to 6.8 kg/cm (g) in
2
place of 7.8 to 8.0 kg/cm (g) at generation point. Reduction in generated pressure by 0.8 to 1.0
2
kg/cm (g) would definitely save energy up to 6 to 8 %. Reduction of generated pressure by 0.8 to 1.0
Kg/cm2 (g) would save
www.fosterms.com PAGE|41
Photo 2. Indicative photograph for compressed air use in plant
a. It is recommended to replace Existing GI piping Circuit with extruded aluminium piping circuit.
The internal bore of this piping is smooth and corrosion resistant which makes the pressure
differential characteristics of a straight run of this pipe superior to that of steel pipe (less than 0.4
bars). Because it is much lighter than steel pipe the installation is much easier.
b. It is recommended to provide display boards showing the cost of utility, compressed air,
electricity, cooling water, chilled water, etc. This will definitely increase the sense of
responsibility while utilization of utility services by operating and user department.
c. Observed automatic drain traps are installed for air receiver. Kindly note that manual discharge of
moisture through air receiver may have human errors in it. In that situation, moisture may pass
towards pneumatic instruments and would affect the performance of the instrument and
enhance compressed air leakages through quick release fittings, the threaded portion of existing
MS/GI piping structure inside the plant. Ultimately energy used for compressed air generation
goes in waste. Preventive maintenance of automatic condensate drain traps (inside the
compressor unit and air receiver auto drain trap) is necessary to avoid sticking up of the plunger
in the trap and helps in the easy draining of condensate accumulated in the compressed air after-
cooler and air receiver itself.
PAGE|42 www.fosterms.com
Photo 3. Drain Valve of Air Receiver
a. Air receiver pressure gauge should be replaced with liquid paraffin filled gauges and it should regularly
calibrate to avoid damage to human and company property.
b. Facility dept. should concentrate on the followings to run the compressors efficiently and effectively.
Photo 4. Pressure gauge on Air Receiver tank
Check the following points to find leaks,
i. Ageing pipework particularly at corroded joints and take off points
www.fosterms.com PAGE|43
ii. Flange connectors where gaskets and pipe dope need replacing.
iii. Fittings that have worked loose or have had excessive strain placed on them.
iv. Manifolds with closely spaced connections. These can be easy to ignore when a leaking fitting is
difficult to access.
v. Flexible hoses with cuts and splits caused by strain and abrasion. Couplings with damaged seals. Grit
may have been picked up during the break and make process.
vi. Drain valves found on air receivers if any, drip leg drains, filters and other equipment can become
stuck open due to pipe scale and sludge or even intentionally left partially open to avoid the
maintenance routine.
vii. Pneumatic components including tools, valves and actuators are all subject to worn and damaged
seals resulting in leaks.
Secrets to run the compressed air system efficiently and cost-effectively, lies in achieving the following
Measures of:
Reducing Air Leaks
Improving End-Use Efficiency by use of quality quick release fittings, air blow guns with air saver
nozzles, installations of proper moisture separators and proper slope for circuit piping from
generation point to end-user points.
Reducing System Air Pressure
Effectively Using Unloading Controls
Adjusting Cascading Set Points
Reducing Run Time and adding Primary Receiver Volume.
3.6 Air Compressors – PET Plant
3.6.1 Energy Performance Assessment – Air Compressors – PET plant
There are four air compressors are installed in the Pet section utility area. Air compressor no. 1, 2, 3 & 4 are
operated with respect to cut off and cut in pressure settings of each individual. Observed working pressure is
2
28 to 30 and 9.3 to 9.6 kg/cm (g) respectively
Table 11. Energy Performance Assessment – Air Compressors – PET plant
Air Air Air Air
Description Compressor Compressor Compressor Compressor
no.1 no.2 no.3 no.4
Make Francois AF Kaeser Atlas Copco Atlas Copco
Type / Model High pressure, N 753 GA 22 GA 30
reciprocating
Mfg. year 2008 2005 NA 2001
Capacity, cfm NA NA 114 cfm 165.17 cfm
Max. inlet temp., °C 45 45 45 45
Motor, kW 55 30 22 30
Rated Dis. Pressure, bar 40 bar 40 bar 10 bar 10 bar
Serial No. 20C087 NA NA ATT 371069
Observations
Working pressure, kg/cm² (g) 32 30 9.3 9.1
Loading Pressure, kg/cm² 30 28 9 8.5
Unloading Pressure, kg/cm² 32 30 10 9.6
Loading Hours, hr NA NA NA 43547 hr
Running Hours, hr NA NA NA 67987 hr
Unloading Hours, hr NA NA NA 24440 hr
Unloading % NA NA NA 35.95 %
Loading % NA NA NA 64.05 %
Ambient Air Temp, °C 40 40 40 40
Discharge Air Temp, °C 105 104.5 92 82
Power taken, kW 65 36 24.8 29.69
Receiver capacity, m 3 0.8 1 0.9 0.5
Connected pipe dia, mm 50 25 25 40
Connected pipe length, mtr 15 1.5 3.5 10
Connected pipe volume, m 3 0.029 0.001 0.0017 0.0126
Dryer volume, m 3 0.01 0 0 0
Total volume of receiver with 0.839 1.001 0.9017 0.5126
pipeline, m 3
Pump up time, min 6.13 3.46 2.56 1.05
Temp correction factor 0.828 0.829 0.86 0.88
Free Air Delivery in cfm 101.5 164.98 98.71 135.38
Volumetric Efficiency, % NA NA 86.58 % 81.96 %
Specific Consumption, kW/cfm 0.640 0.218 0.251 0.219
During system leakage Due to plant is in running condition, leakage quantification test is
quantification test not possible.
Avg. Load time in Min NA
Avg. Unload time in Min NA
System Percentage Leakage NA
System Leakage Quantity in
CFM NA
Energy Loss due to Air Leakage NA
3.6.2 Observations and Recommendations
a. Comp.no. 1, 2, 3 & 4 is running on NA, NA, NA, 64.05 % loading respectively and their volumetric
efficiencies observed are NA, NA, 86.58, 81.96 % respectively.
b. To increase volumetric efficiency up to 88 to 92 %, facility dept. should give attention
towards preventive maintenance, the condition of a suction filter assembly for a choke if any.
c. Observed specific power consumptions for air compressor 1, 2, 3 & 4 are 0.640, 0.218, 0.251,
0.219 kw/cfm respectively. which is more than 0.18 to 0.21 kW /cfm.
PAGE|45 www.fosterms.com
d. For better and consistent performance of air compressor, kindly give proper attention towards the
preventive maintenance of compressor units includes proper overhauling of the unit, regular oil
replacement, cleaning of suction filters, cleaning of radiator assembly to avoid excess specific power
consumption during running condition.
e. With the above measures, we can definitely save,
i. for air compressor no. 3,
( )
ii. for air compressor no. 4,
( )
iii. For air compressor no. 1 and 2 i.e. high-pressure reciprocating compressor, needs detailed
study.
f. It is recommended to replace Existing GI piping Circuit with extruded aluminium piping circuit. The
internal bore of this piping is smooth and corrosion resistant which makes the pressure differential
characteristics of a straight run of this pipe superior to that of steel pipe (less than 0.4 bars). Because
it is much lighter than steel pipe the installation is much easier.
g. It is recommended to provide display boards showing the cost of utility, compressed air, electricity,
cooling water, chilled water, etc. This will definitely increase the sense of responsibility while
utilization of utility services by operating and user department.
h. Observed automatic drain traps are installed for air receiver. Kindly note that manual discharge of
moisture through air receiver may have human errors in it. In that situation, moisture may pass
towards pneumatic instruments and would affect the performance of the instrument and enhance
compressed air leakages through quick release fittings, the threaded portion of existing MS/GI piping
structure inside the plant. Ultimately energy used for compressed air generation goes in waste.
Preventive maintenance of automatic condensate drain traps (inside the compressor unit and air
receiver auto drain trap) is necessary to avoid sticking up of the plunger in the trap and helps in the
easy draining of condensate accumulated in the compressed air after-cooler and air receiver itself.
i. Air receiver pressure gauge should be replaced with liquid paraffin filled gauges and it should
regularly calibrate to avoid damage to human and company property.
www.fosterms.com PAGE|46
3.7 Lighting Load
The lighting load has been found in the whole plant and details regarding it is given in the below table.
Table 12. Lighting Load
Total
Sr. No. Location Type Quantity Watt
(Watt)
1 Blow Mould Shop Metal Halide 21 400 8400
2 PET office Fluorescent Tube lights 2 72 144
Metal Halide 5 400 2000
3 Injection Mould Shop
Fluorescent Tube lights 12 72 864
4 PET warehouse Fluorescent Tube lights 6 72 432
5 Passage Metal Halide 5 400 2000
6 Passage - Bin Washing Area Fluorescent Tube lights 8 72 576
7 Passage RHS to above Fluorescent Tube lights 2 72 144
8 Room near above passage Fluorescent Tube lights 2 72 144
9 Juice/Laban Production Hall Metal Halide 32 400 12800
10 CIP Section Metal Halide 28 400 11200
11 Fresh Product Store Metal Halide 18 400 7200
12 Packing/Labelling Metal Halide 5 400 2000
Fluorescent Tube lights 5 72 360
13 Micro lab (Quality Control)
Fluorescent Tube lights 4 72 288
14 Chiller Panel Room Fluorescent Tube lights 4 108 432
The lighting load has been observed to be of a considerable value consuming a higher amount of energy. So,
tube light mentioned above can be replaced with efficient LED with a lower energy consumption as stated in
the below table.
Table 13. Energy Savings in Lighting with LEDs
LED Replacement
Sr. No. Location Total Savings Energy Cost
Quantity Watt
(Watt) (Watt) savings/year
1 Blow Mould Shop 21 165 3465 4935 1160.7
2 PET office 2 36 72 72 16.9
5 165 825 1175 276.4
3 Injection Mould Shop
12 36 432 432 101.6
4 PET warehouse 6 36 216 216 50.8
5 Passage 5 165 825 1175 276.4
6 Passage - Bin Washing Area 8 36 288 288 67.7
7 Passage RHS to above 2 36 72 72 16.9
8 Room near above passage 2 36 72 72 16.9
9 Juice/Laban Production Hall 32 165 5280 7520 1768.7
10 CIP Section 28 165 4620 6580 1547.6
11 Fresh Product Store 18 165 2970 4230 994.9
12 Packing/Labelling 5 165 825 1175 276.4
5 36 180 180 42.3
13 Micro lab (Quality Control)
4 36 144 144 33.9
14 Chiller Panel Room 4 36 144 288 67.7
Total Savings, OMR/annum 6715.9
PAGE|47 www.fosterms.com
4. ENERGY PERFORMANCE ASSESSMENT OF THERMAL UTILITIES
4.1 Boiler – Dairy Plant
4.1.1 Energy Performance Assessment - Boiler
Table 14. Energy Performance Assessment of Boiler
Sr.no. Description Observations
1 Make M/s. Cleaver-Brooks, USA
2 Rated Capacity 1,67,50,000
3 Rated Steam Pressure, psi 200
4 Model Horizontal, packaged LPG fired
5 Fuel LPG
6 Working hours of boiler, hr 24 hr
7 Calorific value of LPG Btu/kg (GCV) 47035
8 Calorific value of LPG Btu/kg (NCV) 43048
9 Year of Mfg. 2017
10 Volts 415 V,3 Phase
11 Heating surface area., m 2 NA
12 Design Rated Steam Temp., °F 388
25.28 OMR per ton (As per 4500
13 Cost of LPG Rs. per Ton
INR/Ton)
14 Observations during Audit cycle phase (Trial from 11:00 am to 4:00 pm)
15 Cycle duration, hr 5 hr
16 Steam Pressure, psi 100
17 Steam Temp, °F 338
18 Total steam generated, T/cycle 2.2774
19 Feed Water Temp, °F 190.4
20 Feed water TDS, ppm Less than 10 ppm
21 Blowdown water TDS, ppm Less than 3000 ppm
22 Total LPG consumption, T/cycle 0.170
23 Present Blow down, % Less than 5%
Evaporation Ratio, kg of steam/kg of fuel
24 13.40
coal
Enthalpy of steam, Btu/kg @ 100 psi(g) &
25 2628.4
338 °F
Thermal Efficiency, % as per direct
26 75.87
method BEE standards
www.fosterms.com PAGE|48
Table 15. Flue Gas Analysis at Chimney Sampling Point
Sr.no. Description Observations
1 O 2 , % 7.7
2 Stack temp, °F 365
3 CO, % 0.14
4 CO 2 , % 8.79
5 Excess Air, % 53.78
6 Ambient temp, °F 40
7 Heat loss due to dry flue gas, % 7.39
8 Heat loss due to H 2 in fuel, % 8.57
9 Heat loss due to moisture in combustion air, % 0.34
10 Total heat loss, % 16.29
11 Overall combustion efficiency, % 83.71
4.1.2 Observations and Recommendations
1. Observed Oxygen percentage is 7.7 %; it should be in the range of 2 to 5 % for good
combustion. Present oxygen level observed towards higher side in the flue gas. It directly
indicates the presence of excess air which ultimately enhances dry flue gas losses. Observed
excess air percentage is 53.78 %. With proper control on burner FD blower, we can able to
control the excess air percentage up to 10 to 15 %.
2. Observed Carbon dioxide percentage is 8.79 %; it should be in the range of 10 to 13 % for
good combustion in the boiler combustion zone.
3. Observed excess air in the flue gas 53.78 %. It clearly indicates the presence of dry flue gas
losses. This is sheer wastage of LPG fired inside the boiler.
4. Observed thermal efficiency of 75.87 %. Presently boiler runs underrated pressure capacity.
5. It is recommended to analyse LPG for ultimate analysis periodically to keep a close eye on the
quality of LPG utilized.
6. It is observed that no insulation on the boiler feed water tank and a line from it to feed water
pump. To save bare surface heat losses from feed water tank, its necessary to insulate it with
3
rock wool of 4" thick @ 120 kg/m density.
7. From Feed water TDS ppm and boiler drum water TDS ppm, boiler operation facility should fix
the percentage of Blowdown and give it during the running condition. Care should be taken
not to exceed boiler drum TDS ppm level more than 3000 ppm as it reduces the heat transfer
between water and fireside.
8. For better control on boiler operation, boiler operator should check Oxygen percentage in
flue gas on daily basis with the help of pyrite instrument.
9. Steam distribution header needs damaged insulation replacement.
PAGE|49 www.fosterms.com
The words you are searching are inside this book. To get more targeted content, please make full-text search by clicking here.
Discover the best professional documents and content resources in AnyFlip Document Base.
Search