9. Energy Conservation

8/22/2019 9. Energy Conservation

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Energy Conservation RefrigerationEnergy Conservation RefrigerationSystemsSystems

ByBy

J.ILANGUMARANJ.ILANGUMARAN


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REFRIGERATION SYSTEMREFRIGERATION SYSTEM

Vapour compression refrigeration systems (VCR) and VapourVapour compression refrigeration systems (VCR) and Vapourabsorption refrigeration systems (VAR) find wide usage in theabsorption refrigeration systems (VAR) find wide usage in theIndian industry.Indian industry.

Although VCR's are dominating, over 1000 VAR's are in use inAlthough VCR's are dominating, over 1000 VAR's are in use in

India.India.

THE INDIAN SCENARIOTHE INDIAN SCENARIO--MAJOR ADVANCESMAJOR ADVANCES

Widely used in industrial cooling, food retail and airWidely used in industrial cooling, food retail and airconditioning applications.conditioning applications. Cost savings of 25 % are easily available.Cost savings of 25 % are easily available. Efficient operation of refrigeration systems depends on theEfficient operation of refrigeration systems depends on the

following factors :following factors : DesignDesign SelectionSelection InstallationInstallation

Use of the systemUse of the system


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The basic purpose of the refrigeration system is to control &The basic purpose of the refrigeration system is to control &maintain specified temperature.maintain specified temperature. The temperature maintained can be from 10The temperature maintained can be from 10C to 40C to 40C orC or

even less.even less.

Types of Refrigeration SystemsTypes of Refrigeration Systems

Vapour Absorption SystemVapour Absorption System

RefrigerantsRefrigerants

Ammonia and various halo carbon compounds RAmmonia and various halo carbon compounds R -- 11, R11, R -- 12,12,RR -- 22 and R22 and R -- 502 for (VCR)502 for (VCR)

Lithium Bromide, Ammonia (for VAR)Lithium Bromide, Ammonia (for VAR)


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REFRIGERATION SYSTEMREFRIGERATION SYSTEMLoad or Source

Evaporator

CondenserCooler

ExpansionDevice

Compressor

Work

Work

TECHNICAL COMPARISON OF VAPOUR ABSORPTION CHILLER (VAC)& VAPOUR COMPRESSION CHILLER (VCR)

VAC VCR

Equipment : Equipment :

Absorber, Generator, Condenser &

Evaporator

Compressor, Condenser, Thermal Expansion

Valve, Evaporator

Refrigerant : Water Refrigerant : CFC, Ammonia gases etc.

Absorbent : LiBr Absorbent : Not Applicable

Input Required : Steam Input Required : Power


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TECHNICAL COMPARISON OFTECHNICAL COMPARISON OF

VAC & VCRVAC & VCRVAC VCR

Cycle : Cycle :

1. Take the latent heat from outside water

(Chilled Water) in evaporator by

absorbent.

1. Take the latent heat from outside water

(Chilled water) in evaporator by

refrigerant.

.

absorbent.3. These diluted absorbent is heated up

and separate the refrigerant in the

generator.

4. The refrigerant vapour is condensed inthe condenser & the absorbent which

is coming from generator is cooled

down in the absorber. The total cycle

is operated under vacuum condition

i.e.6 mm Hg

. .

compressed by compressor to hightemp. and higher pressure.

3. These high temp. refrigerant gas will be

cooled down in the condenser,

refrigerant become a liquid.4. This refrigerant will be expanded by

thermal expansion valve which is

connected to evaporator.


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VAPOUR COMPRESSION MACHINESVAPOUR COMPRESSION MACHINESTypes based on CompressorsTypes based on Compressors

Reciprocating CompressorReciprocating Compressor Centrifugal CompressorsCentrifugal Compressors Screw Compressors andScrew Compressors and Scroll CompressorsScroll Compressors

TypesTypes Steam BasedSteam Based

Double Effect Steam Fired MachinesDouble Effect Steam Fired Machines Single Effect Steam FiredSingle Effect Steam Fired Oil / Gas BasedOil / Gas Based Hot Water BasedHot Water Based


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STEAM BASED VAMSTEAM BASED VAM

Double Effect Steam Fired MachinesDouble Effect Steam Fired Machines

Steam pressureSteam pressure : 3.5 kg / cm2 to 10 kg / cm2: 3.5 kg / cm2 to 10 kg / cm2 CapacityCapacity : 40 TR to 1400 TR : 40 TR to 1400 TR Sp. ConsumptionSp. Consumption : 4.5 kg / hr @ 8 kg / cm2 / TR: 4.5 kg / hr @ 8 kg / cm2 / TR

Single Effect Steam FiredSingle Effect Steam Fired Sp. ConsumptionSp. Consumption : 4.5 kg / hr @ 8 kg / cm2 / TR: 4.5 kg / hr @ 8 kg / cm2 / TR CapacityCapacity : 70 TR to 1400 TR : 70 TR to 1400 TR

Sp. ConsumptionSp. Consumption : 8.5 kg / hr @ 3 kg / cm2 / TR: 8.5 kg / hr @ 3 kg / cm2 / TR


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VAPOUR ABSORPTION MACHINESVAPOUR ABSORPTION MACHINES

Oil / Gas Based VAMOil / Gas Based VAM

FuelsFuels :: Kerosene, Diesel, LPG, LNG,Kerosene, Diesel, LPG, LNG,

Natural gas & Furnace OilNatural gas & Furnace Oil CapacityCapacity :: 30 TR to 770 TR 30 TR to 770 TR

Hot Water Fired VAMHot Water Fired VAM

SourceSource :: Hot Water (minimum ofHot Water (minimum of8585C)C)

CapacityCapacity :: 30 TR to 650 TR 30 TR to 650 TR


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DEVELOPMENTS IN THE FIELD OF VAMDEVELOPMENTS IN THE FIELD OF VAM

Split Evaporator for Improved Output andSplit Evaporator for Improved Output andCoefficient of Performance (COP)Coefficient of Performance (COP)

Drain Heat Exchangers for improved oilDrain Heat Exchangers for improved oilconsumptionconsumption

CuproCupro--nic e in Con enser an A sor ernic e in Con enser an A sor er Maintenance Friendly Design for HeatMaintenance Friendly Design for Heat

ExchangersExchangers

Leak Proof Service ValvesLeak Proof Service ValvesVacuum Pump ImprovementVacuum Pump Improvement


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SPLIT EVAPORATOR FOR IMPROVED OUTPUT AND COPSPLIT EVAPORATOR FOR IMPROVED OUTPUT AND COP

Conventional SystemConventional System

Lower Shell of VAMLower Shell of VAM

Split into two sectionsSplit into two sections One each for Evaporator & AbsorberOne each for Evaporator & Absorber

Improved DesignImproved Design -- Split into three sectionsSplit into three sections -- Evaporation section split into twoEvaporation section split into two

-- One each on side of the AbsorberOne each on side of the Absorber


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SPLIT EVAPORATOR FOR IMPROVEMENT OUTPUTSPLIT EVAPORATOR FOR IMPROVEMENT OUTPUT

How ?How ?

Improved DesignImproved DesignAllows uniform flow of the evaporated vapoursAllows uniform flow of the evaporated vapours Optimal Absorption of refrigerant vapours byOptimal Absorption of refrigerant vapours by

LiBr in the AbsorberLiBr in the Absorber Results inResults in Improvement in Evaporation rateImprovement in Evaporation rate Enhanced OutputEnhanced Output


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BENEFITS OF VAMBENEFITS OF VAM

NonNon--dependence on Electrical Powerdependence on Electrical Power Environmentally Clean & friendlyEnvironmentally Clean & friendly Lesser Down TimeLesser Down Time

Lower Noise LevelLower Noise Level AvailabilityAvailability Continuous and StepContinuous and Step--less Modulation andless Modulation and

LIMITATIONS OF VAMLIMITATIONS OF VAM

Minimum chilled waterMinimum chilled water

Temperature possibleTemperature possible :: + 4.5+ 4.5 CC Only water cooled condensers are available commercially.Only water cooled condensers are available commercially. High initial investmentHigh initial investment


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APPLICATIONS OF VAM IN INDUSTRIESAPPLICATIONS OF VAM IN INDUSTRIES

AutomobileAutomobile EngineeringEngineering

PetrochemicalsPetrochemicals PharmaceuticalPharmaceutical CementCement

Soft DrinksSoft Drinks ChemicalsChemicals FertilizersFertilizers

RefineryRefinery Commercial Establishments and moreCommercial Establishments and more


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ENERGYCONSERVATION OPPORTUNITIESENERGYCONSERVATION OPPORTUNITIES

Replace Chiller (Usually Smaller)Replace Chiller (Usually Smaller)

Reduce Refrigeration LoadsReduce Refrigeration Loads Minimize Chiller OperationMinimize Chiller Operation Isolate S ecial LoadsIsolate S ecial Loads

Lower Condenser Water TemperatureLower Condenser Water Temperature Reasons to replace a chillerReasons to replace a chiller

Future Refrigerant Cost / AvailabilityFuture Refrigerant Cost / Availability Future Maintenance Repair CostFuture Maintenance Repair Cost

Efficiency ImprovementsEfficiency Improvements


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REDUCTION IN REFRIGERATION LOADREDUCTION IN REFRIGERATION LOAD

The refrigeration load itself can be reduced byThe refrigeration load itself can be reduced bythe following methods :the following methods :

Reduction in the use of RefrigerationReduction in the use of Refrigeration Improved InsulationImproved Insulation

e uc on n ux ary oa se uc on n ux ary oa s

REDUCTION IN USE OF REFRIGERATIONREDUCTION IN USE OF REFRIGERATION

Whether it is necessary?Whether it is necessary? If required, how much and what temperature?If required, how much and what temperature?


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IMPROVED INSULATIONIMPROVED INSULATION

Insulation of Pipe Lines, Valves, Flanges etc.Insulation of Pipe Lines, Valves, Flanges etc. Better Design of Building and enclosuresBetter Design of Building and enclosures

Provision of Films, Curtains, Venetian BlindsProvision of Films, Curtains, Venetian Blinds Orientation of WindowsOrientation of Windows Provision of Natural Cooling and LightingProvision of Natural Cooling and Lighting

P anting o TreesP anting o Trees

ENERGY CONSERVATION OPPORTUNIES ISOLATEENERGY CONSERVATION OPPORTUNIES ISOLATESPECIAL LOADSSPECIAL LOADS

Computer RoomComputer Room Control RoomsControl Rooms Office Administrative BuildingOffice Administrative Building


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ENERGY CONSERVATION OPPORTUNIESENERGY CONSERVATION OPPORTUNIES

Optimize Cooling Tower Fan EnergyOptimize Cooling Tower Fan Energy Raise Chilled Water TemperatureRaise Chilled Water Temperature

Optimize staging of Multiple ChillersOptimize staging of Multiple Chillers Eliminate bypass through deEliminate bypass through de--energized Chillersenergized Chillers Enhance Heat Transfer Surfaces for Efficiency GainsEnhance Heat Transfer Surfaces for Efficiency Gains

Minimize Pump perationMinimize Pump peration Optimize Use of Cheap Rate Non Peak Hour PowerOptimize Use of Cheap Rate Non Peak Hour Power Using Cooling Tower Water if possibleUsing Cooling Tower Water if possible

Use Variable Speed for part load operationUse Variable Speed for part load operation Avoid Hot Gas bypassAvoid Hot Gas bypass Availability of Waster heat, low cost steam vapourAvailability of Waster heat, low cost steam vapour

absorption refrigeration.absorption refrigeration.


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ENERGY CONSERVATION OPPORTUNIESENERGY CONSERVATION OPPORTUNIES

Temperature Drop between condensing andTemperature Drop between condensing andevaporator temperatures leads to power savingevaporator temperatures leads to power saving

doublydoubly

A unit operating atA unit operating at -- 3030CC uses more than twiceuses more than twice

-- .. Reduction in condenser water temperature byReduction in condenser water temperature by11CC or raising Chilled Water Temperature byor raising Chilled Water Temperature by

11CC leads to 1 to 1.5 % saving in powerleads to 1 to 1.5 % saving in powerconsumptionconsumption


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EFFECT OF EVAPORATION TEMPERATUREEFFECT OF EVAPORATION TEMPERATURE

Evaporation RefrigerationCompressor Shaft

Power kWkW / ton

5 67.58 55.3 0.81

0 56.07 52.3 0.94

- . . .

- 10 37.20 46.6 1.25

- 20 23.12 38.7 1.67

MAINTENANCE ASPECTS IN REFRIGERATION Remove Excess ChargeClean the condenser periodicallyAdd refrigeration to correct load

Maintain oil temperature between 50 - 60C


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ENERGY SAVINGS OPPORTUNITIES DISCUSSEDENERGY SAVINGS OPPORTUNITIES DISCUSSED

IN DETAILIN DETAIL

Efficient Scroll CompressorsEfficient Scroll Compressors

Secondary Chilled Water Pump OpportunitiesSecondary Chilled Water Pump OpportunitiesVSD used in Centrifugal CompressorVSD used in Centrifugal Compressor

Ammonia VAR SystemAmmonia VAR System Cooling Tower Energy OptimizationCooling Tower Energy Optimization


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SCROLL COMPRESSORSSCROLL COMPRESSORS

The scroll compressor is the heart of the newThe scroll compressor is the heart of the newgeneration premium, high efficiency heat pumps andgeneration premium, high efficiency heat pumps and

air conditioners.air conditioners. Range Available : 5 TRRange Available : 5 TR -- 15 TR15 TR Scroll Compressors are finding acceptance inScroll Compressors are finding acceptance in

Principle of Working Two identical spirals or scrollsPrinciple of Working Two identical spirals or scrolls One scroll remains stationery while the other orbitsOne scroll remains stationery while the other orbits

around the firstaround the first

As this motion occurs, gas is drawn into the scrollsAs this motion occurs, gas is drawn into the scrollsandand Moved in increasingly smaller pockets towards theMoved in increasingly smaller pockets towards the

centercenter


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WORKING OF SCROLL COMPRESSORSWORKING OF SCROLL COMPRESSORS

At this point, the gas now compressed to aAt this point, the gas now compressed to a

high pressure is discharged from a part in thehigh pressure is discharged from a part in thefixed scroll.fixed scroll.

compressed simultaneously, creating smooth,compressed simultaneously, creating smooth,nearly continuous operation.nearly continuous operation.


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ENERGY EFFICIENCY OF SCROLLENERGY EFFICIENCY OF SCROLL

COMPRESSORCOMPRESSOR 10 % more energy efficient than reciprocating10 % more energy efficient than reciprocating

CompressorsCompressors

Near 100 % volumetric efficiencyNear 100 % volumetric efficiency The scroll compression process occurs during a fullThe scroll compression process occurs during a full

540540 of rotation where 180of rotation where 180 of rotation inof rotation in

rec proca ng compressorsrec proca ng compressors Results in : Smoother Compression & dischargeResults in : Smoother Compression & discharge The scroll design does not require a dynamic valveThe scroll design does not require a dynamic valve

where piston Compressor needs.where piston Compressor needs.

Suction & discharge process in a scroll compressor isSuction & discharge process in a scroll compressor isphysically separated.physically separated.

Results in : Lesser heat transfer, which improvesResults in : Lesser heat transfer, which improves

overall efficiency.overall efficiency.


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OPERATING PERFORMANCEOPERATING PERFORMANCE

ReliabilityReliability -- Fewer Moving PartsFewer Moving Parts DurabilityDurability -- Axial and radial compliance makeAxial and radial compliance make

the scroll compressor more tolerant to liquidthe scroll compressor more tolerant to liquidrefrigerant and debris.refrigerant and debris.

Lower SounLower Soun Flooded starts normally will not harm scrollFlooded starts normally will not harm scrollcompressorcompressor


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SECONDARY CHILLLED WATER SYSTEMSECONDARY CHILLLED WATER SYSTEM

ENERGY CONSERVATION OPPORTUNITIESENERGY CONSERVATION OPPORTUNITIES

ApplicationApplication -- used for distribution of chilledused for distribution of chilled

water to the loads from the primary productionwater to the loads from the primary productionloop.loop.

--

Proposed SystemProposed System -- VSD for Sec. Chilled WaterVSD for Sec. Chilled WaterPumpPump


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Case StudyCase Study

SECONDARY CHILLED WATER SYSTEM ECOSECONDARY CHILLED WATER SYSTEM ECO

Flow

%

Hours

%

Hours

Run

Power Consumption

kW

Energy Input

kWh

1 2 1 2

30 5 438 23.33 4.73 10 219 2 072

40 5 438 23.56 6.08 10 319 2 663

50 10 876 24.03 8.01 21 050 7 017

60 10 876 24.71 10.61 21 646 9 294

70 10 876 25.62 14.04 22 443 12 299

80 20 1752 26.76 18.54 46 884 32 482

90 30 2628 28.17 24.28 74 031 63 808

100 10 876 30.22 31.48 26 473 27 576

100 8760 2 33 064 1 57 211

1 Two Way Valve Control 2 VSD Control


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SECONDARY CHILLED WATER SYSTEMSECONDARY CHILLED WATER SYSTEMENERGY CONSERVATION OPPORTUNITIESENERGY CONSERVATION OPPORTUNITIES

BasisBasis :: 30 kW Pump30 kW Pump Comparison with Two Way ValveComparison with Two Way Valve SavingsSavings :: 75 840 kWh75 840 kWh

VARIABLE SPEED DRIVE FOR CENTRIFUGAL COMPRESSORVARIABLE SPEED DRIVE FOR CENTRIFUGAL COMPRESSOR

Model Case StudyModel Case Study :: Ref. SCREX 99Ref. SCREX 99 Chiller Plant CapacityChiller Plant Capacity :: 500 TR 500 TR

Power ConsumptionPower Consumptionat Full Loadat Full Load :: 250 kW ( 0.5 kW / TR )250 kW ( 0.5 kW / TR ) 82 % of total power consumption is by Chiller Motor in Chilled82 % of total power consumption is by Chiller Motor in Chilled

Water System.Water System.

Constant speed chillers handle lower loads by gradually closingConstant speed chillers handle lower loads by gradually closingat set of guide vanes on the Compressor inlet while keeping theat set of guide vanes on the Compressor inlet while keeping themotor turning at full speedmotor turning at full speed

Closing the vanes create friction losses in Refrigerant flow,Closing the vanes create friction losses in Refrigerant flow,productingproducting


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RECOMMENDATIONRECOMMENDATION

Single stage compressors are especially well suited forSingle stage compressors are especially well suited forVariable Speed Drive.Variable Speed Drive.

Power consumption can be reduced upto 30 % byPower consumption can be reduced upto 30 % byinstalling VFD.installing VFD. Annual savingAnnual saving :: 95065 kWh95065 kWh

LIMITATIONSLIMITATIONS

Multistage compressors have the added complexity ofMultistage compressors have the added complexity ofmaintaining the appropriate inter stage pressure,maintaining the appropriate inter stage pressure,hence varying the speed will upset this balance andhence varying the speed will upset this balance andthis will penalise the performance of the compressor.this will penalise the performance of the compressor.


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OTHER BENEFITS OF VSDOTHER BENEFITS OF VSD

Ideal soft starter (Inrush amp for VSD neverIdeal soft starter (Inrush amp for VSD neverexceeds the 100 % FLA of the motor whereexceeds the 100 % FLA of the motor wheresolid state starter of Star Delta starter have 300solid state starter of Star Delta starter have 300-- 400 % FLA).400 % FLA).

Addition of VSD enhances the unloadingAddition of VSD enhances the unloadingcapability of a Centrifugal chiller by varying thecapability of a Centrifugal chiller by varying thespeed prior to closing the guide vanes.speed prior to closing the guide vanes.

Quite OperationQuite OperationVSD also come with automatic power factorVSD also come with automatic power factor

correctioncorrection


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VSD Vs CONSTANT SPEED OPERATINGVSD Vs CONSTANT SPEED OPERATING

COST COMPARISONCOST COMPARISONLoad

Poin

ts

TonsECWT

F

Annual

hours

Annual kWh

Alt 1 Alt 2 Savings

1 200 78 100 12 758 10 172 2 586

2 250 80 300 45 806 37 065 8 741

4 350 84 2 150 4 50 487 4 05 091 45 396

5 400 86 1 800 4 38420 4 12 744 25 676

6 450 88 200 56 709 55 754 955

7 500 90 100 32 438 33 851 -1 413

Total 5 150 11 26 479 10 31 414 95 065

Alt 1 is for the chiller with constant speed unitAlt 2 is for VSD chiller.


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CASE STUDY ON HOT WATER FIREDCASE STUDY ON HOT WATER FIRED

VAPOUR ABSORPTION MACHINEVAPOUR ABSORPTION MACHINEA continuous process industry in TN.A continuous process industry in TN.

DG set detailsDG set details CapacityCapacity :: 2 Nos of 4 MW2 Nos of 4 MW

Supply air @ 40Supply air @ 40CC Design parameter is at 25Design parameter is at 25CC

Average Units generationAverage Units generation (per DG set)(per DG set) :: 3400 kW / hr3400 kW / hr


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RECOMMENDATIONSRECOMMENDATIONS

One number of Vapour Absorption Machine (VAM)One number of Vapour Absorption Machine (VAM)connected to one DG set hot water circuit with aconnected to one DG set hot water circuit with aprovision to link the second DG set, in case the first isprovision to link the second DG set, in case the first isunder maintenance.under maintenance.

Capacity of VAMCapacity of VAM : 173 TR: 173 TR Chilled water flowChilled water flow : 104.6 m3 hr: 104.6 m3 hr

Chilled water inlet / outlet temp.Chilled water inlet / outlet temp. : 12 / 17: 12 / 17CC

Hot water flowHot water flow : 144 m3 / hr: 144 m3 / hr Hot water inlet / outlet tempHot water inlet / outlet temp : 91 / 85: 91 / 85CC

Cooling Water FlowCooling Water Flow : 300 m3 / hr: 300 m3 / hr Cooling water inlet / outlet temp : 32 / 36.5Cooling water inlet / outlet temp : 32 / 36.5CC Power consumption for VAHP : 3.7 kWPower consumption for VAHP : 3.7 kW

Charge air cooling requirement : 73 TRCharge air cooling requirement : 73 TR


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SAVINGS IN FUEL CONSUMPTION BY VAMSAVINGS IN FUEL CONSUMPTION BY VAM

Savings in specific fuel consumption / kWSavings in specific fuel consumption / kW6.5 gm / kW6.5 gm / kW

Savings in fuel cost / yearSavings in fuel cost / year : Rs. 39 lakhs: Rs. 39 lakhs Savings due to additional loading in DG :Rs. 50 lakhs.Savings due to additional loading in DG :Rs. 50 lakhs. otal savin s : Rs. 89 lakhsotal savin s : Rs. 89 lakhs

Other benefit : 100 TR of chilled water for plant useOther benefit : 100 TR of chilled water for plant use(OR) 173 TR of Chilled Water(OR) 173 TR of Chilled Water

Investment of Rs. 44 lakhsInvestment of Rs. 44 lakhs


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AMMONIA VAPOUR ABSORPTIONAMMONIA VAPOUR ABSORPTION

REFRIGERATION (AVAR)REFRIGERATION (AVAR) -- FEATURESFEATURESAbility to operate at rates higher thanAbility to operate at rates higher than

nameplate capacitors without negativenameplate capacitors without negativeconsequences. Inertial storage at low loads toconsequences. Inertial storage at low loads tomeet transient with sizable spikes.meet transient with sizable spikes.

Putting up with interrupted heat supply whilePutting up with interrupted heat supply whilemaintaining cold supply on continuous mode.maintaining cold supply on continuous mode.Low pressure steam and available waste heatLow pressure steam and available waste heat

sources can be utilized.sources can be utilized.


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FACTORS IN FAVOUR OF AVARFACTORS IN FAVOUR OF AVAR

Increase in cost of electricity and low cost steamIncrease in cost of electricity and low cost steamgeneration through various available resources.generation through various available resources.

Improvement in COP (COP has gone up from 0.4 toImprovement in COP (COP has gone up from 0.4 to0.56, in latest machines)0.56, in latest machines)

ExampleExample COPCOP : 0.56: 0.56 Evaporation tempEvaporation temp :: -- 3030CC

Heating media tempHeating media temp : 172: 172CC BasisBasis : Cooling Water at 33: Cooling Water at 33CC


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BARRIERS IN AVARBARRIERS IN AVAR

Premium first costPremium first cost Lack of familiarityLack of familiarity

maintenance problemmaintenance problem Poorer COP (even though heat energy pricePoorer COP (even though heat energy price

compared to electricity is low)compared to electricity is low)

Ineffective or nonexistent sales structure forIneffective or nonexistent sales structure forcommercial implementation after R & D.commercial implementation after R & D.

S O O CS O O C


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BENEFITS OF AVAR OVER VCRBENEFITS OF AVAR OVER VCR

BasisBasis

Cooling Water at 33Cooling Water at 33CC

Evaporation Temperature at 20Evaporation Temperature at 20CC Unit TR RequirementUnit TR Requirement

..

Steam CostSteam Cost : Rs 500 / MT: Rs 500 / MTAVAR System RequirementsAVAR System Requirements

Steam Quantity Requirement : 9 kgSteam Quantity Requirement : 9 kg Power ConsumptionPower Consumption : 0.25 kWh: 0.25 kWh Total CostTotal Cost : Rs 5.5 / TR: Rs 5.5 / TR


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AVAR OPERATING BENEFITSAVAR OPERATING BENEFITS Compression Refrigeration Requirements :Compression Refrigeration Requirements : Power ConsumptionPower Consumption :: 1.75 kWh1.75 kWh Operating CostOperating Cost :: Rs 7.0 / TR Rs 7.0 / TR

Difference in operating CostDifference in operating Cost :: Rs 1.5 / TR Rs 1.5 / TR

COOLING TOWERCOOLING TOWER -- FANS APPLICATIONFANS APPLICATION

Cooling Towers are used to cool condenser water in waterCooling Towers are used to cool condenser water in watercooled Chiller Systems.cooled Chiller Systems.

Water cooled chiller systems provide 20 % more efficientWater cooled chiller systems provide 20 % more efficientcooling system than air cooled chiller systems.cooling system than air cooled chiller systems.

Conventional Control SystemsConventional Control Systems ON / OFF ControlON / OFF Control Two Speed MotorsTwo Speed Motors Adjustable Pitch Blade FansAdjustable Pitch Blade Fans


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COOLING TOWERCOOLING TOWER -- CASE STUDYCASE STUDY

Case Study on Cooling Tower fan with VSD Drive.Basis : 30 kW fanComparison with two speed motor is madeSavings : 83 588 kWhBENEFITS OF VSD CONTROL OVER TWO SPEED MOTOR CONTROL

Flow Hours Hours

Run

Power Consumption kWEnergy Input

kWh

% % 1 2 1 2

. .

50 15 1314 12.80 4.83 16 819 6 347

60 35 3066 12.80 7.85 39 245 24 068

70 20 1752 30.00 11.93 52 560 20 901

80 15 1314 30.00 17.27 39 420 22 693

90 10 876 30.00 24.16 26 280 21 164

100 0 0 0 0.00 0 0

100 8760 1 79 930 96 342

1 Two Way Valve Control 2 VSD Control


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SUM UPSUM UP

Several Energy Saving Opportunities existSeveral Energy Saving Opportunities exist Selection of the VCR & VAR Systems dependSelection of the VCR & VAR Systems depend

upon cost of Energy Inputupon cost of Energy Input

New technologies give sizable Energy SavingsNew technologies give sizable Energy Savings Retrofits for Evaporator give good scope forRetrofits for Evaporator give good scope forsavingssavings

Savings in Auxiliaries system improvementSavings in Auxiliaries system improvement Fit case to implementFit case to implement

9. Energy Conservation

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