Mr D than Voltas

8/8/2019 Mr D than Voltas

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Conceptual view of a chilled-water

cooled air-conditioning system

Pattern of Designed ambienttemp. v/s actual ambient temp.

0

5

10

15

20

25

30

35

0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 0:00

ambient temp.

design temp.

Engineered Variable Speed Control


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Water flow requirement based on actualambient temperature

0

20

40

60

80

100

120

140

160

0:00

3:00

6:00

9:00

12:00

15:00

18:00

21:00

0:00

Flow requirement

Design flow

Actual flow Supplied

Engineered Variable Speed Control

Saving on Compressor

0

20

40

60

80

100

120

140

Unloader control Speed control


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Category I

NO INVESTMENTS

Close monitoring of HVAC system:-

Improve and/or implement good maintenance practices

Periodically checking actual performance of equipment &

comparing with rated performance

Clean heat exchangers periodically

Replace lubricating oil periodically

Check water quality periodically & provide treatment if required

Check water wastage / leakage's in pump /valve glands

and arrest them.

Check chilled-water pipe insulation & line losses

Constantly challenge the process requirement &

change it.e.g.

- increase room temp- increase chilled water temp

- reduce flow rate

- increase relative humidity,etc

Category I

NO INVESTMENTS


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Overdesigned equipments / variable load

- Replace motors with suitable new efficient motors.

- Introduce engineered variable speed control.

- Redesigning a water / air distribution.

- Introduce a de-superheater to get benefit of

a. Free hot water & reduced fuel consumption.

b. Reduced kW/TR ratio through reduction in discharge pressure

Category 2MODERATE INVESTMENTS

Category 2

MODERATE INVESTMENTS

Replacement of inefficient chilled and condenser

Water pumps.

Change the process of air-conditioning.

(use recirculatory air instead of treated fresh air.)

Automize the operation to avoid human interference

and error.


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Category 3Capital Investment

Replace old plants completely or partly with

energy efficient plants.

Energy savings measures through efficient

operation and maintenance

The suction Temperature, discharge pressure of compressors to bemaintained at optimum level Ensure all indicators are working properly

Monitor and maintain record on oil level

Condensers Remove scale, algae and adopt for suitable water treatment

Lesser the water temperature more the COP

Routine cleaning of Cooling coils / condenser coils

Stop condenser water pump when compressor not working


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Impact due to the Variation of Condenser Water

Inlet Temperature on

Power Consumption

Water Temp

(0C)

Refrigeration

Capacity

(tons)

Specific

Power

Consumption

Increase in

kW/TR

(%)

26.7 31.5 1.17 -

35.0 21.4 1.27 8.5

40.0 20.0 1.41 20.5

CHILLERS

EFFECT OF SCALE ON CONDENSING

TEMPERATURE


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0

44.00.048.004

33.00.036.003

22.00.024.002

11.00.012.001

5.50.006.0005

1.10.001.0001

00

Power IncreaseScale ThicknessClean

0

44.00.048.004

33.00.036.003

22.00.024.002

11.00.012.001

5.50.006.0005

1.10.001.0001

00

Power IncreaseScale ThicknessClean

Energy Saving Opportunities in Cooling

Towers Follow manufacturers recommended clearances around cooling towers and relocate

or modify structures that interfere with the air intake or exhaust.

Optimise cooling tower fan blade angle on a seasonal and/or load basis.

Correct excessive and/or uneven fan blade tip clearance and poor fan balance. .

Install new nozzles to obtain a mor e uniform water pattern

Periodically clean cooling tower distribution nozzles.

Cover hot water basins to minimize algae growth that contributes to fouling.

Optimize blow down flow rate, as per limit.


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EM&RBG17INTEGRATED SYSTEMS INCOMPARABLE

VALUE

ENERGY SAVING OPPORTUNITIES-AHU

Adjust air cooling set points according torequirement.Optimized start stop of air handling unitsIntroduce zone isolation & variable air flow for

large office area or hallVariable speed drive for AHUs

Collect condensate collection from AHUs forlandscaping .

Energy Saving Opportunities in Cooling Coils

Bio-film, Mould, Bacteria, Dust = Plugged up coils, Reduced Air flow,

Higher running costs, Reduces the efficiency


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Energy Conservation Opportunities in

Pumping Systems

Ensure adequate Net Positive Suction Head at site of installation

Operate pumps near best efficiency point.

Modify pumping system and pumps losses to minimize throttling.

Adapt to wide load variation with variable speed drives or sequenced control

of multiple units.

Stop running multiple pumps - add an auto-start for an on-line spare or add a

booster pump in the problem area.

Increase fluid temperature differentials to reduce pumping rates in case of

heat exchangers.

Repair seals and packing to minimize water loss by dripping.

Balance the system to minimize flows and reduce pump power requirements.

SCREW V/S RECIPROCATING

Description Existing Recip Screw

Cap installed 120 TR x 5= 600 TR 240 TR x 2= 480 TR

Cap derived @ 65% 400 Tr

KW/TR 1.1 0.67

K.w 440 322

Op hrs 24 24

Op days 365 365

Tariff 6.57 6.57

Usage factor 0.8 0.8

Op cost 202.58 lacs 148.25 lacs

Annual expected savings 54.33 lacs

Pay back period 19 months

Investment for new

Screw Chiller 86.7 lacs

Case Study II


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Existing Pumps KW New Pump KW Saving in KW

Condensor Pump 31 KW 24 KW 9 KW

CHW Pump 41 KW 23 KW 18 KW

Saving in Rs WHrs / Day Day / Year Rs / KWH Total Saving

Cond. Pump 9 KW 24 hrs. 350 3.50/- 2,64,00/-

CHW Pump 18 KW 24 hrs. 350 3.50/- 5,29,900/-

Total 7,93,800/-

Replacement of Chilled & Condenser Water Pumps

Cost of New Pump Rs 7,30,000/-

Payback period = 11 months

Savings in Rs

Case Study III

THANK YOU

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Mr D than Voltas