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Cooling Technology Institutewww.cti.org
BenefitsBenefits ofof
Water-Cooled SystemsWater-Cooled Systemsvsvs
Air-Cooled SystemsAir-Cooled Systemsforfor
Air-Conditioning ApplicationsAir-Conditioning Applications
Written by: Michael D.Pugh
Cooling Technology Institutewww.cti.org
U.S. Government commitment toU.S. Government commitment toreduce greenhouse gas emissionsreduce greenhouse gas emissionscan have a significant impact oncan have a significant impact on
HVAC system considerationsHVAC system considerations
Cooling Technology Institutewww.cti.org
Kyoto Conference onKyoto Conference on Global Warming Global Warming
�� International effort to control greenhouseInternational effort to control greenhousegas emissionsgas emissions
�� Greenhouse gasses include:Greenhouse gasses include:——Carbon Dioxide (COCarbon Dioxide (CO22))
——Methane (CHMethane (CH44))
——Nitrous Acid (NNitrous Acid (N22O)O)
——Hydrofluorocarbons Hydrofluorocarbons ((HFC sHFC s))
——PerfluorocarbonsPerfluorocarbons ( (PFC sPFC s))
——Sulfur Sulfur Hexafluorides Hexafluorides (SF(SF44))
Cooling Technology Institutewww.cti.org
U.S. Commitment to KyotoU.S. Commitment to KyotoConferenceConference
�� Kyoto Protocol signed by ex-President BillKyoto Protocol signed by ex-President BillClinton in October, 1997Clinton in October, 1997
�� Commits U.S. to reduce greenhouse gasCommits U.S. to reduce greenhouse gasemissions to 7% below 1990 levels by 2012emissions to 7% below 1990 levels by 2012
�� Ratification by U.S. Senate pendingRatification by U.S. Senate pending
Cooling Technology Institutewww.cti.org
Total U.S. Greenhouse GasTotal U.S. Greenhouse GasEmissions by GasEmissions by Gas
Cooling Technology Institutewww.cti.org
U.S. Greenhouse Gas Emissions U.S. Greenhouse Gas Emissions
Carbon Dioxide (COCarbon Dioxide (CO22) emissions account for) emissions account for85% of U.S. greenhouse gas emissions85% of U.S. greenhouse gas emissions
Cooling Technology Institutewww.cti.org
Major COMajor CO22 Emission Sources Emission Sources
�� Transportation IndustryTransportation Industry
�� Heavy IndustryHeavy Industry
�� Utility IndustryUtility Industry
Cooling Technology Institutewww.cti.org
Major COMajor CO22 Emission Sources Emission Sources Utility Industry Utility Industry
�� Fossil Fuel Burning Power PlantsFossil Fuel Burning Power Plants——Produce 55% of U.S. electricityProduce 55% of U.S. electricity
——Accounts for 68% of the COAccounts for 68% of the CO22 emission emissionreductions required for Protocol compliancereductions required for Protocol compliance
——Addition of exhaust gas scrubbers notAddition of exhaust gas scrubbers noteconomically viable for most plantseconomically viable for most plants
——Only 16% (193 of 1,207) of Power Plants haveOnly 16% (193 of 1,207) of Power Plants haveexhaust gas scrubbersexhaust gas scrubbers
Cooling Technology Institutewww.cti.org
U.S. Government Plan to reduceU.S. Government Plan to reduceCOCO22 Emissions from Power Plants Emissions from Power Plants
�� Convert to less carbon intensive fuels orConvert to less carbon intensive fuels ornon-carbon fuelsnon-carbon fuels——Taxation of carbon fuelsTaxation of carbon fuels
——Regulation of emissions for new plantsRegulation of emissions for new plants
�� Reduce energy demandReduce energy demand——New energy-saving technologiesNew energy-saving technologies
�� Improve efficiency of equipment andImprove efficiency of equipment andsystemssystems
Cooling Technology Institutewww.cti.org
Fossil Fuel Burning Power PlantsFossil Fuel Burning Power Plants
�� Air-conditioning systems drive many powerAir-conditioning systems drive many powerplant peak loads and have been identified asplant peak loads and have been identified asenergy reduction opportunityenergy reduction opportunity
Cooling Technology Institutewww.cti.org
U.S. Actions Impacting HVACU.S. Actions Impacting HVAC Systems and Equipment Systems and Equipment
�� EPA ENERGY STAR ProgramEPA ENERGY STAR Program¨̈ Actively promotes participation in economicallyActively promotes participation in economically
justified energy saving projectsjustified energy saving projects
�� Energy Policy Act of 1992Energy Policy Act of 1992——ASHRAE Standard 90.1 as basis for energyASHRAE Standard 90.1 as basis for energy
efficiency for commercial buildings.efficiency for commercial buildings.——ASHRAE 90.1 revised in June,1999ASHRAE 90.1 revised in June,1999——submitted to D.O.E. for acceptancesubmitted to D.O.E. for acceptance——Recently adopted for ICC energy codeRecently adopted for ICC energy code
Energy Saving System Designs . . .Energy Saving System Designs . . .
. . .our . . .ourEnvironmental ResponsibilityEnvironmental Responsibility
Cooling Technology Institutewww.cti.org
Basic Air Conditioning SystemsBasic Air Conditioning Systems
�� Large Buildings ( >400 tons)Large Buildings ( >400 tons)——Water cooled systems provide clear-cutWater cooled systems provide clear-cut
economic and environmental justification.economic and environmental justification.
�� Mid-size Buildings (200 - 400 tons)Mid-size Buildings (200 - 400 tons)——Air cooled systems may offer first costAir cooled systems may offer first cost
incentive to sacrifice energy efficiencies ofincentive to sacrifice energy efficiencies ofwater cooled systems.water cooled systems.
Cooling Technology Institutewww.cti.org
Theoretical Building Profile Theoretical Building Profile
�� Building loadBuilding load——400 tons400 tons
�� Building configurationBuilding configuration——square w/ five (5) floorssquare w/ five (5) floors
——one (1) air handling fan / floorone (1) air handling fan / floor
�� Air VolumeAir Volume——350 CFM/ton350 CFM/ton
——3-1/2 w.g. T.S.P.3-1/2 w.g. T.S.P.
Cooling Technology Institutewww.cti.org
400 Ton System Comparisons400 Ton System Comparisons
�� Chiller systems:Chiller systems:——Air-Cooled ChillerAir-Cooled Chiller
——Centrifugal ChillerCentrifugal Chiller
�� Packaged systems:Packaged systems:——Roof -Top UnitsRoof -Top Units
——Self-Contained UnitsSelf-Contained Units
Cooling Technology Institutewww.cti.org
System Energy Requirements System Energy Requirements�� 400 Ton Air-Cooled Chiller System400 Ton Air-Cooled Chiller System
KW /UnitKW /Unit Total KW Total KW
CompressorCompressor 406.00 406.00 406.00406.00
Condenser fans 62.50 Condenser fans 62.50 62.50 62.50
Air handling units 22.37Air handling units 22.37 111.85111.85
Chilled HChilled H220 pump 14.92 0 pump 14.92 14.9214.92
Total KWTotal KW 595.27595.27
�� KW/ton= 595.27/400 = KW/ton= 595.27/400 = 1.49KW/ton1.49KW/ton
Cooling Technology Institutewww.cti.org
System Energy Requirements System Energy Requirements�� 400 Ton Centrifugal Chiller System400 Ton Centrifugal Chiller System
KW /Unit KW /Unit Total KW Total KW
CompressorCompressor 220.0 220.00 220.0 220.00
Air handling unitsAir handling units 22.3722.37 111.85 111.85
Chilled HChilled H220 pump 14.920 pump 14.92 14.92 14.92
Condenser HCondenser H220 pump 11.19 11.190 pump 11.19 11.19
Cooling tower fan 18.65 Cooling tower fan 18.65 18.6518.65
Total KWTotal KW 376.61 376.61
�� KW/ton= 376.61/400 = KW/ton= 376.61/400 = 0.94KW/ton0.94KW/ton
Cooling Technology Institutewww.cti.org
Theoretical 400 Ton SystemTheoretical 400 Ton SystemComparisonsComparisons
�� Chiller systemsChiller systems——Air-cooled chiller system . . . . . . . Air-cooled chiller system . . . . . . . 1.49KW/ton1.49KW/ton
——Centrifugal chiller system . . . . . . . Centrifugal chiller system . . . . . . . 0.94KW/ton0.94KW/ton
Cooling Technology Institutewww.cti.org
System Energy Requirements System Energy Requirements
�� 400 Ton Roof-Top System: (5)80 Ton Units400 Ton Roof-Top System: (5)80 Ton Units KW /Unit KW /Unit Total KW Total KW
CompressorCompressor 74.65 74.65 373.25373.25
Air handling fan 29.84Air handling fan 29.84 149.20149.20
Condenser fanCondenser fan 8.60 8.60 43.0043.00
Total KW Total KW 565.45565.45
�� KW/ton= 565.45/400 = KW/ton= 565.45/400 = 1.42KW/ton1.42KW/ton
Cooling Technology Institutewww.cti.org
System Energy Requirements System Energy Requirements�� 400 Ton Self-Contained System: (5)80 Ton400 Ton Self-Contained System: (5)80 Ton
UnitsUnits KW /Unit KW /Unit Total KW Total KW
CompressorCompressor 63.12 63.12 315.60 315.60Air handling fan 22.37Air handling fan 22.37 111.85 111.85Condenser HCondenser H22O pump 11.19O pump 11.19 11.19 11.19Cooling tower fanCooling tower fan 18.75 18.75 18.7518.75Total KWTotal KW 457.39 457.39
�� KW/ton= 457.39/400 = KW/ton= 457.39/400 = 1.14KW/ton1.14KW/ton
Cooling Technology Institutewww.cti.org
System Energy Comparison System Energy Comparison
�� Chiller systemsChiller systems——Air-cooled chiller system . . . . . . . Air-cooled chiller system . . . . . . . 1.49KW/ton1.49KW/ton
——Centrifugal chiller system . . . . . . . Centrifugal chiller system . . . . . . . 0.94KW/ton0.94KW/ton
�� Packaged systemsPackaged systems——Roof-top units . . . . . . . . . . . . . . . Roof-top units . . . . . . . . . . . . . . . 1.42KW/ton1.42KW/ton
——Self-contained units . . . . . . . . . . . .Self-contained units . . . . . . . . . . . .1.14KW/ton1.14KW/ton
Cooling Technology Institutewww.cti.org
Basic HVAC System OptionsBasic HVAC System Options
�� Water-cooled systemsWater-cooled systems——More energy-efficient than air-cooled systemsMore energy-efficient than air-cooled systems
——Support environmental efforts to controlSupport environmental efforts to controlgreenhouse gas emissionsgreenhouse gas emissions
Cooling Technology Institutewww.cti.org
Kyoto ConferenceKyoto Conference
If we do it right, protecting the climate willIf we do it right, protecting the climate willyield not costs, but profits; not burdens, butyield not costs, but profits; not burdens, butbenefits; not sacrifice, but a higherbenefits; not sacrifice, but a higherstandard of livingstandard of living
President Bill ClintonPresident Bill Clinton
Cooling Technology Institutewww.cti.org
Installed Cost Estimate SourcesInstalled Cost Estimate Sources
�� Air Cooled Chiller . . . . $350/Air Cooled Chiller . . . . $350/TrTr x 1.50 x 1.50
�� Centrifugal Chiller . . . . $250/Centrifugal Chiller . . . . $250/Tr Tr x 1.50x 1.50
�� Roof Top Units . . . . . . .$550/Roof Top Units . . . . . . .$550/TrTr x 1.25 x 1.25
�� Self Contained Units . . $400/Self Contained Units . . $400/Tr Tr x 1.50x 1.50
�� Air Handling Units . . . . $1.00/CFM x 1.25Air Handling Units . . . . $1.00/CFM x 1.25
�� Cooling Towers . . . . . . .$45/Cooling Towers . . . . . . .$45/TrTr x 1.50 x 1.50
�� Pump/Piping . . . . . . . . . Means Mech. Est.Pump/Piping . . . . . . . . . Means Mech. Est.
Cooling Technology Institutewww.cti.org
Installed Cost EstimateInstalled Cost Estimate Air Cooled Chiller System Air Cooled Chiller System
�� 400 ton air cooled chiller . . . . . . . $210,000400 ton air cooled chiller . . . . . . . $210,000
�� (5) 28,000 CFM air handlers . . . . $175,000(5) 28,000 CFM air handlers . . . . $175,000
�� 1,000 LF chilled water piping . . . $ 67,0001,000 LF chilled water piping . . . $ 67,000
�� Chilled water pump . . .. . . .. . . . .. $ 3,600Chilled water pump . . .. . . .. . . . .. $ 3,600
�� Total installed cost . . . . . . . . Total installed cost . . . . . . . . $455,600$455,600
Cooling Technology Institutewww.cti.org
Installed Cost EstimateInstalled Cost EstimateCentrifugal Chiller SystemCentrifugal Chiller System
——400 ton centrifugal chiller . . . . . . .$150,000400 ton centrifugal chiller . . . . . . .$150,000
——400 ton cooling tower . . . . .. . . . . $ 27,000400 ton cooling tower . . . . .. . . . . $ 27,000
——(5) 28,000 CFM air handlers . . . . $175,000(5) 28,000 CFM air handlers . . . . $175,000
——1,000 LF chilled water piping . . . $ 67,0001,000 LF chilled water piping . . . $ 67,000
——400 LF condenser water piping . . .$ 26,800400 LF condenser water piping . . .$ 26,800
——Chilled water pump . . .. . . .. . . . .. $ 3,600Chilled water pump . . .. . . .. . . . .. $ 3,600
——Condenser water pump . . . . . . . . . .$ 4,000Condenser water pump . . . . . . . . . .$ 4,000
——Mechanical equipment room . . . $ 45,000Mechanical equipment room . . . $ 45,000
——Total installed cost . . . . . . . . Total installed cost . . . . . . . . $498,400$498,400
Cooling Technology Institutewww.cti.org
Installed Cost EstimateInstalled Cost EstimateRoof-Top Unit SystemRoof-Top Unit System
�� (5) 80 ton roof top units . . . .(5) 80 ton roof top units . . . .
�� Installed cost . .. . . .. . . Installed cost . .. . . .. . . $275,000$275,000
Cooling Technology Institutewww.cti.org
Installed Cost EstimateInstalled Cost EstimateSelf-Contained Unit SystemSelf-Contained Unit System
�� (5) 80 ton self-contained units .. . . . . . . . $240,000(5) 80 ton self-contained units .. . . . . . . . $240,000
�� Closed circuit cooling tower . . . . . . . . . . $ 54,000Closed circuit cooling tower . . . . . . . . . . $ 54,000
�� Condenser water pump . . . . . . . . . . . . . . $ 4,000Condenser water pump . . . . . . . . . . . . . . $ 4,000
�� Condenser water piping . . . . . . . . . . . . . .Condenser water piping . . . . . . . . . . . . . . $ 26,800 $ 26,800
�� Installed cost . . . . . . . . . . . . . Installed cost . . . . . . . . . . . . . $324,800$324,800
Cooling Technology Institutewww.cti.org
Installed Cost Summary Installed Cost Summary
InstalledInstalled CostCost
Chiller systemsChiller systems Air-Cooled Chiller Air-Cooled Chiller $455,600$455,600 Centrifugal Chiller Centrifugal Chiller $498,400$498,400Packaged systemsPackaged systemsRoof-Top Roof-Top $275,000$275,000Self-ContainedSelf-Contained $324,800$324,800
Cooling Technology Institutewww.cti.org
System Energy Cost AssumptionsSystem Energy Cost Assumptions
�� 1800 Equivalent Full Load Hours per Year1800 Equivalent Full Load Hours per Year
�� $0.06 per KW-Hour$0.06 per KW-Hour
�� $12 per KW Demand Charge for 6 Months$12 per KW Demand Charge for 6 Months
Cooling Technology Institutewww.cti.org
Annual Energy Cost Comparison Annual Energy Cost Comparison
Total Energy DemandTotal Energy Demand TotalTotal
KWKW CostCost CostCost CostCost
Chiller systemsChiller systems
Air-cooled chiller 595.27 $ 64,289 $42,860 Air-cooled chiller 595.27 $ 64,289 $42,860 $107,149$107,149
Centrifugal chiller 376.61 $ 40,674 $27,116 Centrifugal chiller 376.61 $ 40,674 $27,116 $ 67,790$ 67,790
Packaged systemsPackaged systems
Roof-top 565.45 $ 61,069 $40,712 Roof-top 565.45 $ 61,069 $40,712 $101,781$101,781
Self-contained 457.39 $ 49,398 $32,932 Self-contained 457.39 $ 49,398 $32,932 $ 82,330$ 82,330
Cooling Technology Institutewww.cti.org
System Cost Summary System Cost Summary
InstalledInstalled Energy Energy CostCost CostCost
Chiller systemsChiller systemsAir-cooled chiller $455,600Air-cooled chiller $455,600 $107,149$107,149Centrifugal chiller $498,400 Centrifugal chiller $498,400 $ 67,790$ 67,790Packaged systemsPackaged systemsRoof-top $275,000Roof-top $275,000 $101,781$101,781Self-containedSelf-contained $324,800 $324,800 $ 82,330$ 82,330
Cooling Technology Institutewww.cti.org
Water UsageWater Usage
�� Water cooled systems recycle 95% of theWater cooled systems recycle 95% of thetotal watertotal water
�� A small portion of the water is bled fromA small portion of the water is bled fromthe system to control the build-up ofthe system to control the build-up ofimpuritiesimpurities
Bleed Rate = Bleed Rate = Evaporation RateEvaporation Rate
Cycles of Concentration - 1 Cycles of Concentration - 1
Cooling Technology Institutewww.cti.org
Water Usage and CostWater Usage and Cost(400 ton sample system)(400 ton sample system)
Evaporation Rate = 3.0 GPM/100 tonsEvaporation Rate = 3.0 GPM/100 tons
= 12.0 GPM/400 ton system = 12.0 GPM/400 ton system
Cooling Technology Institutewww.cti.org
Water Usage and CostWater Usage and Cost(400 ton sample system)(400 ton sample system)
Evaporation Rate = 3.0 GPM/100 tonsEvaporation Rate = 3.0 GPM/100 tons
= 12.0 GPM/400 ton system = 12.0 GPM/400 ton system
Bleed Rate = Bleed Rate = 12.0 GPM12.0 GPM
4 cycles -1 4 cycles -1
= 4.0 GPM = 4.0 GPM
Cooling Technology Institutewww.cti.org
Water Usage and CostWater Usage and Cost(400 ton sample system)(400 ton sample system)
Evaporation Rate = 3.0 GPM/100 tonsEvaporation Rate = 3.0 GPM/100 tons
= 12.0 GPM/400 ton system = 12.0 GPM/400 ton system
Bleed Rate = Bleed Rate = 12.0 GPM12.0 GPM
4 cycles -1 4 cycles -1
= 4.0 GPM = 4.0 GPM
Consumption = Evaporation + BleedConsumption = Evaporation + Bleed
= 12.0 GPM + 4.0 GPM = 12.0 GPM + 4.0 GPM
= 16.0 GPM = 16.0 GPM
Cooling Technology Institutewww.cti.org
Water Usage and CostWater Usage and Cost(400 ton sample system)(400 ton sample system)
�� Annual Water ConsumptionAnnual Water Consumption——16.0 GPM X 60 Min/Hr x 1800 16.0 GPM X 60 Min/Hr x 1800 EqEq FLH FLH
——1,728,000 gallons/year1,728,000 gallons/year
�� Annual Water & Sewer CostAnnual Water & Sewer Cost——1,728,000 gal X $3.00/1000 gal1,728,000 gal X $3.00/1000 gal
——$5,184$5,184
Cooling Technology Institutewww.cti.org
Water Quality and Control CostWater Quality and Control CostConsiderationsConsiderations
�� Water-cooled systems require chemicalWater-cooled systems require chemicaltreatment to control scale/corrosion andtreatment to control scale/corrosion andbiological growthsbiological growths
�� These costs must be included in a costThese costs must be included in a costanalysis of water cooled and air cooledanalysis of water cooled and air cooledsystemssystems
Cooling Technology Institutewww.cti.org
Annual Water Treatment CostsAnnual Water Treatment Costs(400 ton sample system)(400 ton sample system)
�� Full Service Water TreatmentFull Service Water Treatment——Average annual program costs- $1.00/ton/monthAverage annual program costs- $1.00/ton/month
——400400 Tr Tr X $1.00/ X $1.00/TrTr//MnthMnth X 6 X 6 mnth mnth = $2,400/year = $2,400/year
Cooling Technology Institutewww.cti.org
Annual Water Cost EstimateAnnual Water Cost Estimate(400 ton sample system)(400 ton sample system)
Water Consumption - $5,184Water Consumption - $5,184
Water Treatment Water Treatment $2,400$2,400
Annual Water Cost Annual Water Cost $7,584$7,584
Cooling Technology Institutewww.cti.org
System Cost Summary System Cost Summary
InstalledInstalled Energy Energy Water Water CostCost Cost Cost CostCost
Chiller systemsChiller systemsAir-Cooled chiller Air-Cooled chiller $455,600 $455,600 $107,149$107,149 N/A N/ACentrifugal chiller $498,400 $ 67,790Centrifugal chiller $498,400 $ 67,790 $7,584 $7,584Packaged systemPackaged systemRoof-Top Units $275,000Roof-Top Units $275,000 $101,781$101,781 N/AN/ASelf-ContainedSelf-Contained $324,800 $324,800 $ 82,330 $ 82,330 $7,584 $7,584
Cooling Technology Institutewww.cti.org
System Cost Summary System Cost Summary
InstalledInstalled Energy Energy Water Water Payback Payback CostCost Cost Cost CostCost YrsYrs
Chiller systemsChiller systemsAir-Cooled chiller Air-Cooled chiller $455,600 $455,600 $107,149$107,149 N/AN/A Base BaseCentrifugal chiller $498,400 $ 67,790Centrifugal chiller $498,400 $ 67,790 $7,584$7,584 1.3 1.3Packaged systemPackaged systemRoof-Top Units $275,000Roof-Top Units $275,000 $101,781$101,781 N/A N/A BaseBaseSelf-ContainedSelf-Contained $324,800 $324,800 $ 82,330 $ 82,330 $7,584$7,584 4.2 4.2
Cooling Technology Institutewww.cti.org
HVAC System Considerations HVAC System Considerations
Cost analysis must consider the economicCost analysis must consider the economicimpact that environmental and electricimpact that environmental and electricpower generation issues will have onpower generation issues will have onenergy prices in the near future.energy prices in the near future.
Cooling Technology Institutewww.cti.org
Kyoto Protocol Impacted EnergyKyoto Protocol Impacted EnergyPrices to Commercial Market*Prices to Commercial Market*
�� Projected Energy Price Increases (PProjected Energy Price Increases (PVV))——2005 Projected Increase. . . . . . . . 2005 Projected Increase. . . . . . . . + 17.3%+ 17.3%
——2010 Projected Increase . . . . . . . 2010 Projected Increase . . . . . . . + 65.3%+ 65.3%
�� * * per 1998 Energy Information Administration(EIA) report titledper 1998 Energy Information Administration(EIA) report titledImpacts of the Kyoto Protocol on U.S. Energy Markets an d EconomicImpacts of the Kyoto Protocol on U.S. Energy Markets an d EconomicActivityActivity
Cooling Technology Institutewww.cti.org
2010 Kyoto Impact on Simple 2010 Kyoto Impact on SimplePayback AnalysisPayback Analysis
Installed EnergyInstalled Energy Water Water CostCost Cost Cost CostCost
Chiller systemsChiller systemsAir-Cooled Chiller $455,600Air-Cooled Chiller $455,600 $177,153 $177,153 N/AN/ACentrifugal Chiller $498,400 Centrifugal Chiller $498,400 $112,079 $112,079 $7,584$7,584 Packaged systemPackaged systemRoof -Top units $275,000Roof -Top units $275,000 $168,278 $168,278 N/A N/ASelf-ContainedSelf-Contained $324,800 $324,800 $136,119 $136,119 $7,584$7,584
Cooling Technology Institutewww.cti.org
2010 Kyoto Impact on Simple 2010 Kyoto Impact on SimplePayback AnalysisPayback Analysis InstalledInstalled Energy Energy WaterWater Payback Payback CostCost Cost Cost CostCost YrsYrs
Chiller systemsChiller systemsAir-Cooled Chiller $455,600Air-Cooled Chiller $455,600 $177,153 $177,153 N/AN/A BaseBaseCentrifugal Chiller $498,400 Centrifugal Chiller $498,400 $112,079 $112,079 $7,584$7,584 0.750.75Packaged systemPackaged systemRoof -Top units $275,000Roof -Top units $275,000 $168,278 $168,278 N/A N/A BaseBaseSelf-ContainedSelf-Contained $324,800 $324,800 $136,119 $136,119 $7,584$7,584 2.0 2.0
Cooling Technology Institutewww.cti.org
Deregulation of Electric PowerDeregulation of Electric PowerGeneration IndustryGeneration Industry
Cooling Technology Institutewww.cti.org
Generation Transmission Distribution
Electric Power IndustryElectric Power Industry
Generation Transmission Distribution
Cooling Technology Institutewww.cti.org
Cooling Technology Institutewww.cti.org
Deregulation of Electric PowerDeregulation of Electric PowerGeneration IndustryGeneration Industry
�� Assuming no Kyoto ProtocolAssuming no Kyoto Protocol, 1998 U.S., 1998 U.S.Gov tGov t report projected reduction in average report projected reduction in averageretail electricity price from $0.067KWH toretail electricity price from $0.067KWH to$0.060/KWH by 2010 due to competitive$0.060/KWH by 2010 due to competitiveclimate established by deregulation.climate established by deregulation.
�� Agriculture Dept report(March, 1999)Agriculture Dept report(March, 1999)predicted 19 states expected higherpredicted 19 states expected higherelectricity prices as low cost producers sellelectricity prices as low cost producers sellinto higher price marketsinto higher price markets
Cooling Technology Institutewww.cti.org
DeregulationDeregulationExperienceExperience
Cooling Technology Institutewww.cti.org
Electric Power GenerationElectric Power Generation�� Industry standard - 15% more electricIndustry standard - 15% more electric
generating capacity than requiredgenerating capacity than required
�� Automatic brownout warnings occur whenAutomatic brownout warnings occur whenonly 10% more electric generating capacityonly 10% more electric generating capacityis availableis available
Cooling Technology Institutewww.cti.org
U.S. Electric Generating CapacityU.S. Electric Generating Capacity
�� 1980 1980 30% excess capacity30% excess capacity
�� 2000 2000 14% excess capacity14% excess capacity
�� 2005 < 10% excess capacity predicted2005 < 10% excess capacity predicted
Cooling Technology Institutewww.cti.org
Electric Generating CapacityElectric Generating Capacity�� Overall North American generatingOverall North American generating
capacity is marginalcapacity is marginal
�� Many areas with generating capacityMany areas with generating capacityshortfallsshortfalls——CaliforniaCalifornia
——New YorkNew York
——New EnglandNew England
——ArizonaArizona
——KansasKansas
——IndianaIndiana
Cooling Technology Institutewww.cti.org
TransmissionTransmission�� In 1995, there were only 25,000In 1995, there were only 25,000
transactions where electricity was sold fromtransactions where electricity was sold fromone region to anotherone region to another
�� In 1999, there were more than 2,000,000In 1999, there were more than 2,000,000transactions where electricity was sold fromtransactions where electricity was sold fromone region to anotherone region to another
Cooling Technology Institutewww.cti.org
Transmission GridlockTransmission Gridlock
�� There are sharp There are sharp locationallocational price differentials price differentialsdue to the inability to transmit enoughdue to the inability to transmit enoughpower from region to region.power from region to region.
Cooling Technology Institutewww.cti.org
Transmission GridlockTransmission Gridlock
�� In many areas the transmission lines can tIn many areas the transmission lines can tcarry any more power, and lines can t becarry any more power, and lines can t beupgraded fast enoughupgraded fast enough
�� Some areas with transmission problemsSome areas with transmission problems——CaliforniaCalifornia
——Dallas/Ft. WorthDallas/Ft. Worth
——ChicagoChicago
——NYCNYC
Cooling Technology Institutewww.cti.org
DistributionDistribution
�� Local distribution systems can t handleLocal distribution systems can t handleincreasing peak loadsincreasing peak loads
�� Cause of blackouts in NYC, Long Island,Cause of blackouts in NYC, Long Island,Chicago and DetroitChicago and Detroit
Cooling Technology Institutewww.cti.org
The power market is moving toThe power market is moving to
Real-Time PricingReal-Time Pricing
What does Real-Time pricingWhat does Real-Time pricingmean?mean?
High summer daytime ratesHigh summer daytime ratesExamplesExamples
�� San Diego $7.00/kWhSan Diego $7.00/kWh
�� Maine, Connecticut and NYC $6.00/kWhMaine, Connecticut and NYC $6.00/kWh
�� Texas $0.70/kWhTexas $0.70/kWh
�� Montana $0.13/kWhMontana $0.13/kWh
What does Real-Time pricingWhat does Real-Time pricingmean?mean?
LowLow summer night rates summer night rates
Cooling Technology Institutewww.cti.org
Proposed Texas UtilitiesProposed Texas UtilitiesTime-of-Day Rate StructureTime-of-Day Rate Structure
0.00
0.05
0.10
0.15
M 2 4 6 8 10 N 2 4 6 8 10 M
Hour
$ p
er K
WH
Source: Deregulation in Texas and the Impact on Rate Structures for Thermal Storage Applications, J. Michael Sherburne - February 2000
$0.01
$0.13
Cooling Technology Institutewww.cti.org
University of North CarolinaUniversity of North CarolinaHourly Price - July 23, 1999Hourly Price - July 23, 1999
0.00
0.05
0.10
0.15
0.20
0.25
8 9 10 11 N 1 2 3 4 5 6 7
Hour
$ p
er K
WH
Source: Real-time Electrical Rates and Thermal Utilities, Engineered Systems - July 2000
$0.02
$0.23
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What will be the result ofWhat will be the result ofReal-Time pricing?Real-Time pricing?
Highest electricity prices willHighest electricity prices willcoincide with peak air-conditioningcoincide with peak air-conditioning
loadsloads
Energy Saving System Designs . . .Energy Saving System Designs . . .
. . .our . . .ourEnvironmental ResponsibilityEnvironmental Responsibility
Energy Saving System Designs . . .Energy Saving System Designs . . .
. . .our . . .ourFiscal ResponsibilityFiscal Responsibility
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EPA Climate Wise Program-EPA Climate Wise Program-Wise Rules to Energy EfficiencyWise Rules to Energy Efficiency
——Process Cooling Wise Rule 1.Process Cooling Wise Rule 1. Installing energy Installing energyefficient chillers and refrigeration systems canefficient chillers and refrigeration systems cansave 1.2% of a facility s total energy use withsave 1.2% of a facility s total energy use withan average simple payback of 23 months.an average simple payback of 23 months.
——Process Cooling Wise Rule 2.Process Cooling Wise Rule 2. Free cooling Free coolingwith cooling tower water can reduce a facility swith cooling tower water can reduce a facility stotal energy use by about 1% with an averagetotal energy use by about 1% with an averagesimple payback of 14 monthssimple payback of 14 months
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EPA Climate Wise Program-EPA Climate Wise Program-Wise Rules to Energy EfficiencyWise Rules to Energy Efficiency
�� Process Cooling Wise Rule 3.Process Cooling Wise Rule 3. Free Freecooling can reduce cooling system energycooling can reduce cooling system energyuse by as much as 40% depending onuse by as much as 40% depending onlocation and load profile.location and load profile.
�� Process Cooling Wise Rule 4.Process Cooling Wise Rule 4. Increasing Increasingchilled water temperature by 1chilled water temperature by 1 Deg Deg F Freduces chiller energy use by 0.6% to 2.5%reduces chiller energy use by 0.6% to 2.5%
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EPA Climate Wise Program-EPA Climate Wise Program-Wise Rules to Energy EfficiencyWise Rules to Energy Efficiency
——Process Cooling Wise Rule 5. Process Cooling Wise Rule 5. ReducingReducingcondenser pressure by 10 condenser pressure by 10 psipsi can decrease can decreaserefrigeration system energy use per ton ofrefrigeration system energy use per ton ofrefrigeration by about 6%.refrigeration by about 6%.
——Process Cooling Wise Rule 6. Process Cooling Wise Rule 6. For each degreeFor each degreedecrease in condenser cooling waterdecrease in condenser cooling watertemperature, until optimal water temperature istemperature, until optimal water temperature isreached, there is a decrease in chiller energyreached, there is a decrease in chiller energyuse by up to 3.5%.use by up to 3.5%.
there s simply nothere s simply nosubstitute for rawsubstitute for raw(chiller)(chiller)efficiencyefficiency
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Equipment Cost Comparison*
Centrifugal ChillerFirst Cost . . .
$250/ton
Means Mechanical Cost Data
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Equipment Cost Comparison*Equipment Cost Comparison*
Centrifugal ChillerFirst Cost . . .
$250/ton
Means Mechanical Cost Data
Cooling Tower
First Cost . . .
50/ton
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Lower the designLower the design
condenser watercondenser watertemperature.temperature.
Energy Saving Tip
ARI Nominal CondenserARI Nominal CondenserWater Rating ConditionWater Rating Condition
3 GPM / Ton3 GPM / Ton10 Deg F Temperature Rise10 Deg F Temperature Rise85 Deg F Condenser Water85 Deg F Condenser Water
Cooling towers can beCooling towers can beeconomically selected toeconomically selected toprovide condenser waterprovide condenser watertemperatures within 4 Degtemperatures within 4 Deg
F ( or less) of theF ( or less) of theambient wet bulbambient wet bulb
temperature.temperature.
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Effect of Condenser WaterEffect of Condenser WaterTemperature on Chiller EnergyTemperature on Chiller Energy CWCW Typ Typ Chiller Chiller EnergyEnergy
Temp.Temp. Energy Energy SavingsSavings
85 Deg F85 Deg F 0.570 kW/ton0.570 kW/ton Base Base
83 Deg F83 Deg F 0.542 kW/ton0.542 kW/ton 5% 5%
80 Deg F80 Deg F 0.524 kW/ton0.524 kW/ton 8% 8%
75 Deg F75 Deg F 0.484 kW/ton0.484 kW/ton 15% 15%
70 Deg F70 Deg F 0.450 kW/ton0.450 kW/ton 21% 21%
Rule of Thumb for SavingRule of Thumb for SavingChiller EnergyChiller Energy
Chiller energy is reduced 2%Chiller energy is reduced 2%for every 1 Deg F offor every 1 Deg F of
reduced condenser waterreduced condenser watertemperaturetemperature
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Typical Office BuildingTypical Office Building500 Ton System500 Ton System
Operating SeasonOperating Season8 Months / Year8 Months / Year2,500 Equiv. Full Load Hours2,500 Equiv. Full Load Hours
$ 0.08/$ 0.08/kWHkWH Energy Rate Energy Rate
$ 10/kW Demand Charge$ 10/kW Demand Charge
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System Economics with EnergySaving Cooling Tower
Nominal Cooling
Tower Selection . . .
1500 GPM 95/85/78
30 HP Fan Motor
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System Economics with EnergySaving Cooling Tower
Nominal Cooling
Tower Selection . . .
1500 GPM 95/85/78
30 HP Fan Motor
Energy Saving Cooling
Tower Selection . . .
1500 GPM 93/83/78
30 HP Fan Motor
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System Economics with EnergySaving Cooling Tower
Nominal Cooling
Tower Selection . . .
1500 GPM 95/85/78
30 HP Fan Motor
Energy Saving Cooling
Tower Selection . . .
1500 GPM 93/83/78
30 HP Fan Motor
First Cost Premium. . . . . . . . $7,800
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Chiller Energy Savings with 2 Deg F Colder Condenser WaterTypical Chiller Energy
Based on 85 Deg F
Condenser Water:
0.570 kW/ton
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Chiller Energy Savings with 2 Deg F Colder Condenser WaterTypical Chiller Energy
Based on 85 Deg F
Condenser Water:
0.570 kW/ton
Typical Chiller Energy
Based on 83 Deg F
Condenser Water:
0.542 kW/ton
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Chiller Energy Savings with 2 Deg F Colder Condenser WaterTypical Chiller Energy
Based on 85 Deg F
Condenser Water:
0.570 kW/ton
Typical Chiller Energy
Based on 83 Deg F
Condenser Water:
0.542 kW/ton
Saves 0.028 kW/ton
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Annual Energy Savings withAnnual Energy Savings with2 Deg F Colder Condenser Water2 Deg F Colder Condenser Water
Chiller Peak Energy Reduction . . 0.028 kW/tonChiller Peak Energy Reduction . . 0.028 kW/ton
500 Ton System . . . . . . . . . . . . . . . . . 500 Tons500 Ton System . . . . . . . . . . . . . . . . . 500 Tons
Equivalent Full Load Hours / Year. . . 2,500 HrsEquivalent Full Load Hours / Year. . . 2,500 Hrs
Energy Cost . . . . . . . . . . . . . . . .Energy Cost . . . . . . . . . . . . . . . .X 0.08 $/X 0.08 $/kWHkWH
Energy Savings . . . . . . . . . . . . . . . . . . . .$2,800Energy Savings . . . . . . . . . . . . . . . . . . . .$2,800
Demand Savings (0.028 kW/ton XDemand Savings (0.028 kW/ton X
500 Tons X $10/ kW X 8 Months ). . 500 Tons X $10/ kW X 8 Months ). . .$1,120.$1,120
Total Annual Energy Savings. . . Total Annual Energy Savings. . . $3,920$3,920
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Payback Period forPayback Period for2 Deg F Colder Condenser Water2 Deg F Colder Condenser Water
Cooling Tower FirstCooling Tower First
__ __Cost Premium Cost Premium = = $ 7,800 $ 7,800 = = 2.0 Year2.0 Year
Annual Energy Cost $ 3,920 PaybackAnnual Energy Cost $ 3,920 Payback
Savings Savings
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Total Energy SavingsTotal Energy Savings
20 Year System Life20 Year System Life
700,000 kW-H Saved700,000 kW-H Saved
$ 78,400 Saved$ 78,400 Saved
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Energy Saving Tip
Evaluate the additional free
cooling hours with low
design water temperatures.
Additional Free CoolingAdditional Free CoolingEnergy SavingsEnergy Savings
250 Ton Winter Load250 Ton Winter Load
55 Deg F Building Loop Water55 Deg F Building Loop Water
52 Deg F Condenser Water52 Deg F Condenser Water
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System Economics with EnergySaving Cooling Tower
Nominal Cooling
Tower Selection . . .
1500 GPM 95/85/78
Model 33520
30 HP Fan Motor
Winter WB - 42 Deg F
4007 Hours
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System Economics with EnergySaving Cooling Tower
Nominal Cooling
Tower Selection . . .
1500 GPM 95/85/78
30 HP Fan Motor
Winter WB - 42 Deg F
4007 Hour
Energy Saving Cooling
Tower Selection . . .
1500 GPM 93/83/78
30 HP Fan Motor
Winter WB - 45 Deg F
4438 Hours
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System Economics with EnergySaving Cooling Tower
Nominal Cooling
Tower Selection . . .
1500 GPM 95/85/78
30 HP Fan Motor
Winter WB - 42 Deg F
4007 Hour
Energy Saving Cooling
Tower Selection . . .
1500 GPM 93/83/78
30 HP Fan Motor
Winter WB - 45 Deg F
4438 Hours
Additional Energy Savings . . . . . . . . . .$4,265
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Cooling Tower Payback with Free Cooling
Cooling Tower First
Cost Premium = $ 7,800 < 1.0 Year
Annual Energy $3,920 + $4,265 Payback
Cost Savings
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Total Energy Savings
20 Year System Life
1,766,700 kW-H Saved
$ 163,700 Saved
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Energy Saving Tip # 3
Take advantage of low
ambient wet bulb
temperatures.
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ASHRAE 0.4% Wet BulbASHRAE 0.4% Wet BulbTemperaturesTemperatures
LocationLocation Wet Bulb Wet BulbBaltimore, MD Baltimore, MD 78 Deg F78 Deg FNew York, NYNew York, NY 76 Deg F 76 Deg FBoston, MABoston, MA 75 Deg F75 Deg FLos Angeles, CALos Angeles, CA 72 Deg F72 Deg FSeattle, WASeattle, WA 66 Deg F66 Deg FDenver, CODenver, CO 65 Deg F65 Deg F
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Chiller Energy Savings with NominalSystem in Various Locations
Location WB CWT
Baltimore 78 Deg F 85.0 Deg F
New York 76 Deg F 83.5 Deg F
Boston 75 Deg F 82.7 Deg F
Los Angeles 72 Deg F 80.5 Deg F
Seattle 66 Deg F 76.0 Deg F
Denver 65 Deg F 75.0 Deg F
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Chiller Energy Savings with NominalSystem in Various Locations
Location WB CWT Energy
Baltimore 78 Deg F 85.0 Deg F 0.57 kW/T
New York 76 Deg F 83.5 Deg F 0.55 kW/T
Boston 75 Deg F 82.7 Deg F 0.54 kW/T
Los Angeles 72 Deg F 80.5 Deg F 0.53 kW/T
Seattle 66 Deg F 76.0 Deg F 0.49 kW/T
Denver 65 Deg F 75.0 Deg F 0.48 kW/T
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Chiller Energy Savings with NominalSystem in Various Locations
Location WB CWT Energy SaveBaltimore 78 Deg F 85.0 Deg F 0.57 kW/T Base
New York 76 Deg F 83.5 Deg F 0.55 kW/T $2 K
Boston 75 Deg F 82.7 Deg F 0.54 kW/T $3 K
Los Angeles 72 Deg F 80.5 Deg F 0.53 kW/T $4 K
Seattle 66 Deg F 76.0 Deg F 0.49 kW/T $6 K
Denver 65 Deg F 75.0 Deg F 0.48 kW/T $9 K
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Energy Saving TipsEnergy Saving Tips
Tip #1Tip #1 - - Lower the DesignLower the DesignCondenser Water TemperatureCondenser Water Temperature..
Tip #2Tip #2 -- Evaluate Additional Free Evaluate Additional FreeCooling Hours.Cooling Hours.
Tip #3Tip #3 - Take Advantage of Low- Take Advantage of LowAmbient Wet Bulb Temperatures.Ambient Wet Bulb Temperatures.
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ConclusionConclusion�� Air-conditioning system evaluations shouldAir-conditioning system evaluations should
take the pending impact of environmentaltake the pending impact of environmentalissues into considerationissues into consideration
�� Water cooled systems provide the mostWater cooled systems provide the mostenergy efficient systems and can helpenergy efficient systems and can helpprotect building owners and operators fromprotect building owners and operators fromuncertainties in electricity pricing.uncertainties in electricity pricing.
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BenefitsBenefits ofof
Water-Cooled SystemsWater-Cooled Systemsvsvs
Air-Cooled SystemsAir-Cooled Systemsforfor
Air-Conditioning ApplicationsAir-Conditioning Applications
Written by: Michael D.Pugh
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