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High performance-chilled-water-systems ashrae-chicago

  1. 1. High PerformanceChilled WaterSystems Mick Schwedler, PE, LEED® AP Manager Applications Engineering Trane © 2011 Ingersoll Rand
  2. 2. Normal PerformanceChilled Water Systems ASHRAE/IESNA 90.1 (LEED Prerequisite) System configuration Design parameters System control
  3. 3. ASHRAE Standard90.1-2007 Purpose “… Provide minimum requirements for the energy- efficient design of buildings except low-rise residential buildings”
  4. 4. Purpose ofANSI/ASHRAE/IESNAStandard 90.1-2010 To establish minimum energy efficiency requirements of buildings, other than low-rise residential buildings for:1. design, construction, and a plan for operation and maintenance, and2. Utilization of on-site renewable energy resources.
  5. 5. Publication and FinalSavings Estimates Performed by Pacific Northwest National Laboratory (PNNL)  Savingsof 90.1-2010 compared to 90.1-2004  Savings shared are modeled as of January 2011  Includeventilation changes in ASHRAE 62.1 between 1999 and 2007 versions
  6. 6. 90.1 Progress Indicator Including receptacle loads in modeling Including receptacle load in % savings calculation Energy cost savings % Energy savings % Ventilation rate changes between 62.1-1999 24.0 25.5 and 62.1-2007
  7. 7. 90.1 Progress IndicatorExcluding receptacle loads in % savingscalculation only Including receptacle loads in modeling Excluding receptacle load in % savings calculation Energy cost savings % Energy savings % Ventilation rate changes between 62.1-1999 30.1 32.6 and 62.1-2007
  8. 8. LEED Energy andAtmosphere LEED 2009  10% energy cost savings beyond 90.1-2007 LEED 2012  Public Review 2: September 2011  EA Prerequisite: 10% average energy cost and source energy savings beyond 90.1-2010 (new construction)  EA Credit: Credit for reductions beyond 10%
  9. 9. 90.1-2010Chiller EfficienciesPaths A & B Before 1/1/2010 As of 1/1/2010c Test Procedureb Equipment Type Size CategoryUnits Path A Path Bd Full Full Full Load IPLV Load IPLV Load IPLV ARI 550/590 <150 tons EER ≥9.562 ≥10.416 ≥9.562 ≥12.50 NA NA Air-cooled ≥150 tons EER ≥9.562 ≥10.416 ≥9.562 ≥12.75 NA NA <75 tons kW/ton ≤0.780 ≤0.630 ≤0.800 ≤0.600 ≥75 tons and < ≤0.790 ≤0.676 Water Cooled kW/ton ≤0.775 ≤0.615 ≤0.790 ≤0.586 150 tonsElectrically Operated, ≥150 tons andPositive Displacement kW/ton ≤0.717 ≤0.627 ≤0.680 ≤0.580 ≤0.718 ≤0.540 < 300 tons ≥300 tons kW/ton ≤0.639 ≤0.571 ≤0.620 ≤0.540 ≤0.639 ≤0.490 <150 tons kW/ton ≤0.703 ≤0.669 ≥150 tons and ≤0.634 ≤0.596 ≤0.639 ≤0.450 Water Cooled kW/ton ≤0.634 ≤0.596 < 300 tonsElectrically Operated, ≥300 tons and Centrifugal kW/ton ≤0.576 ≤0.549 ≤0.600 ≤0.400 < 600 tons ≤0.576 ≤0.549 ≥600 tons kW/ton ≤0.570 ≤0.539 ≤0.590 ≤0.400 Must meet both full and part load requirements
  10. 10. Heat rejection equipment Fan speed control 7.5 and greater  Capability to operate at 2/3 fan speed or less Exceptions  Climates > 7200 CDD50 (e.g. Miami)  1/3 of fans on multiple fan application
  11. 11. Hydronic systemdesign and control Pump isolation Chilled and hot water reset if >300,000 Btuh  Exception: Variable flow systems that reduce pumping energy
  12. 12. 90.1-2007Hydronic SystemDesign & ControlThese provisions apply if pump systempower > 10 hp:  Must be variable flow unless …  Pump power ≤ 75 hp  ≤ 3 Control valves  Limit demand of individual variable-flow pumps to 30% of design wattage at 50% flow (e.g., use VSD)  Pump head > 100 ft  Motor > 50 hp
  13. 13. WatersideEnergy Recovery required Service Water Heating  24 hrs per day and  Heat rejection > 6 MMBtuh and  SWH load 1 MMBtuh Recover smaller of  60% of heat rejection  Preheat water to 85°F
  14. 14. Configuration Normal Performance Chilled Water production pumps distribution pumpproduction loopdistribution loop two-way valve
  15. 15. Design ParametersNormal PerformanceChilled Water Plant ARI 550/590 Standard Conditions  44°F chilled water  2.4 gpm/ton chilled water (10°F T)  3.0 gpm/ton condenser water (10°F [9.3] T)
  16. 16. ControlNormal PerformanceChilled Water Plant Chilled water distribution pump P at most remote load Cooling tower fans  55°F (as cold as possible) Constant speed condenser water pumps All these “normal” assumptions will be examined
  17. 17. High PerformanceChilled Water Plants Standard high performance  Reduced flow rates, increased ∆Ts  Variable primary flow Advanced high performance  Equipment capabilities  System configurations  System control
  18. 18. a history ofChiller Performance 8.0 centrifugal >600 tonschiller efficiency, COP screw 6.0 150-300 tons scroll <100 tons 4.0 reciprocating <150 tons 2.0 0.0 ASHRAE Standard 90 NBI “best” 90-75 90-75 90.1-89 90.1-99 available (1977) (1980)
  19. 19. chilled water plant design …ProvocationAre our “rules of thumb” … 44 F chilled water supply 10 F T for chilled water system 3 gpm/ton condenser water flow … in need of repair?
  20. 20. High PerformanceDesign Parameters ASHRAE GreenGuide and CoolTools™  Chilled water T: 12°F to 20 °F  Condenser water T: 12°F to 18 °F (multi-stage) Kelly and Chan  Chilled water T: 18°F  Condenser water T: 14.2°F (3.6 - 8.3% energy savings in various climates)
  21. 21. chilled water plant …humid climateBase Design: 450 Tons 0.5% design  Coil, valve and chilled wet bulb: 78 F water piping pressure drop: 80 ft Entering condenser water temperature  Condenser water piping (ECWT): 85 F pressure drop: 30 ft Evaporator and  Pump efficiency: 75% condenser  Pump motor temperature efficiency: 93% differences: 10 F
  22. 22. traditional design …humid climateSystem EnergyConsumption 350Energy Consumption, kW 300 250 200 150 Tower Condenser Water Pump 100 Chilled Water Pump Chiller (100% Load) 50 0 2.4/3.0 Chilled / Condenser Water Flows, gpm/ton
  23. 23. traditional vs. low-flow design …System Summary AtFull Load 350Energy Consumption, kW 300 250 200 150 Tower Condenser Water Pump 100 Chilled Water Pump Chiller (100% Load) 50 0 2.4/3.0 1.5/2.0 Chilled / Condenser Water Flows, gpm/ton
  24. 24. comparison …humid climateSystem Summary At75% Load 350Energy Consumption, kW 300 250 200 150 Tower Condenser Water Pump 100 Chilled Water Pump Chiller (75% Load) 50 0 2.4/3.0 1.5/2.0 Chilled / Condenser Water Flows, gpm/ton
  25. 25. comparison …humid climateSystem Summary At50% Load 350Energy Consumption, kW 300 250 200 150 Tower Condenser Water Pump 100 Chilled Water Pump Chiller (50% Load) 50 0 2.4/3.0 1.5/2.0 Chilled / Condenser Water Flows, gpm/ton
  26. 26. comparison …humid climateSystem Summary At25% Load 350Energy Consumption, kW 300 250 200 150 Tower Condenser Water Pump 100 Chilled Water Pump Chiller (25% Load) 50 0 2.4/3.0 1.5/2.0 Chilled / Condenser Water Flows, gpm/ton
  27. 27. traditional vs. low-flow design…humid climateSavings Summary 20.0 Operating Cost Savings, % 16.5% 10.3% 10.0 6.7% 3.8% 0 25% 50% 75% 100% Load
  28. 28. High PerformanceDesign Parameters kWh/ton/year 600 Chilled water 400 pump 200 Chiller 0 41/16 42/14 43/12 44/10 Chilled water supply temperature/DeltaT
  29. 29. Pipe Size Example90.1-2010 Table 6.5.4.5 800 ton system 3,000 hours of operation Chilled water, variable flow Condenser water, constant flow Past Design ASHRAE GreenGuide Practice ∆T Flow Pipe ∆T Flow Pipe (°F) (gpm) Size (°F) (gpm) Size Chilled 10 1920 10 16 1200 8 Water Condenser 9.4 2400 14 14 1600 12 Water
  30. 30. High PerformanceDesign OptionsEither … Take full energy (operating cost) savingsOr … Reduce piping size and cost Experienced designers use pump, piping and tower savings to select an even more efficient chiller
  31. 31. Reduced flow works forall chiller manufacturers Logan Airport - Boston:  $426,000 Construction cost savings  7.3% operating cost savings Large Chemical Manufacturer -Greenville  $45,000 Excavation and concrete savings  6.5% Operating cost savings Computer Manufacturer - San Francisco  Existing tower, pipe savings  2% Operating cost savings (tower not changed)
  32. 32. Low flow works forretrofit applications Chilled water side  Coil  It’s a simple heat transfer device  Reacts to colder entering water by returning it warmer  Ideal for system expansion
  33. 33. Low flow works forretrofit applications Condenser side retrofit opportunity  Chiller needs to be replaced  Cooling needs have increased by 50%  Cooling tower was replaced two years ago  Condenser pump and pipes are in good shape
  34. 34. Condenser sideretrofit opportunity Existing Retrofit Capacity (tons) 500 750 Flow rate (gpm) 1500 1500 Condenser Entering Water 85 88 Temperature (F) Condenser Leaving Water 95 103 Temperature (F) Design Wet Bulb (F) 78 78
  35. 35. Humid climatesLow flow works forshort piping runs too Condenser Water Side Only - original 350.0 300.0 Energy Consumption (kWh) 250.0 200.0 3.0 gpm/ton 2.0 gpm/ton 150.0 100.0 50.0 0.0 25% 50% 75% 100% System Load
  36. 36. Humid climatesLow flow works forshort piping runs too Condenser Water Side Only ZERO piping pressure drop 350.0 300.0 Energy Consumption (kWh) 250.0 200.0 3.0 gpm/ton 2.0 gpm/ton 150.0 100.0 50.0 0.0 25% 50% 75% 100% System Load
  37. 37. High PerformanceDesign Parameters Low flow benefits systems - no matter whose chiller is being used Low flow works extremely well on existing systems Low flow works on short piping runs
  38. 38. always, always,Always Remember …
  39. 39. Oh, by the way...You may also do this with air
  40. 40. Variable-Primary-Flow Systemsvariable-flow pumps check valves control valve
  41. 41. VPF Savings First cost: 4-8% Annual energy: 3-8% Life-cycle cost: 3-5% http://www.arti-21cr.org/ARI/util/showdoc.aspx?doc=1085
  42. 42. Flow requirementsVPF System Limits (consult manufacturer)  Absolute flows - Minimum and maximum  Flow rate changes  2% of design flow per minute not good enough  10% of design flow per minute borderline  30% of design flow per minute many comfort cooling applications  50% of design flow per minute best Always need a way to ensure minimum flow (bypass)
  43. 43. Chiller Control V a ria b le W a te r F lo w 130 1500 120 1300 110 1100 100 900Water Temp [degF] 90 700 E vaporator W ater F low Flow [gpm] 80 500 70 300 60 100 50 E vap E ntering W ater T em p -100 40 -300 E vap Leaving W ater T em p 30 -500 3:50:00 3:55:00 4:00:00 4:05:00 4:10:00 T im e (h o u r:m in :s e c )
  44. 44. More informationVPF System Http:/trane.com/commercial /library/newsletters.asp (1999 and 2002) “Primary-Only vs. Primary-Secondary Variable Flow Systems,” Taylor, ASHRAE Journal, February 2002 “Don’t Ignore Variable Flow,” Waltz, Contracting Business, July 1997 “Comparative Analysis of Variable and Constant Primary-Flow Chilled-Water-Plant Performance,” Bahnfleth and Peyer, HPAC Engineering, April 2001 “Campus Cooling: Retrofitting Systems,” Kreutzmann, HPAC Engineering, July 2002
  45. 45. High PerformanceChilled Water Plants Standard high performance  Reduced flow rates, increased ∆Ts  Variable primary flow Advanced  Equipment capabilities  System configurations  System control
  46. 46. Equipment CapabilitiesHigh PerformanceChilled Water Plant Constant speed  0.570 FL / 0.479 IPLV Higher efficiency “same price” options  Variable speed (spend money on drive)  Constant speed (spend money on copper) Purchase both a drive and more heat exchange surface Down to 0.45 kW/ton FL available (22% reduction)
  47. 47. Same-price Chiller:Example Performance Option Full Load IPLV (kW/ton) (kW/ton)VSD 0.572 0.357High Efficiency 0.501 0.430
  48. 48. Same-price Chiller:Example Performance 600-ton Replacement Chiller Performance 400 350 300 High_efficiency_85°F 250 VSD_85°F High_efficiency_75°F kW 200 VSD_75°F 150 High_efficiency_65°F VSD_65°F 100 50 0 0% 20% 40% 60% 80% 100% % Load
  49. 49. Example Office building Two 400-ton chillers Comparisons  Base system - constant speed  AFD on both chillers  High efficiency for both chillers  AFD on one chiller  High efficiency for one chiller
  50. 50. What is the actualutility rate? Utility costs  ‘Combined’ utility rates ($0.10 / kWh)  Actual utility rates ($12 / kW and $0.06 / kWh)
  51. 51. Utility rate comparison Simple paybacks, humid climate Combined rate Actual rate on one AFD 6.1 10.8 chiller High efficiency 6.3 7.7 on both AFD 7.2 12.7 chillers High efficiency 7.1 8.3 Using incorrect “combined” rate leads to incorrect decisions
  52. 52. Rule 1 Use actual utility rates
  53. 53. Temperate climatewith economizer Annual operating cost Simple payback $100,000 30 $80,000 25 20 $60,000 15 $40,000 10 $20,000 5 0 Base case AFD on High efficiency AFD on High efficiency both chillers both chillers one chiller one chiller Chiller plant operating cost Simple payback
  54. 54. Temperate climate,no economizer Annual operating cost Simple payback $100,000 12 $80,000 10 8 $60,000 6 $40,000 4 $20,000 2 0 Base case AFD on High efficiency AFD on High efficiency both chillers both chillers one chiller one chiller Chiller plant operating cost Simple payback
  55. 55. Humid climate,no economizer Annual operating cost Simple payback $100,000 14 $80,000 12 10 $60,000 8 $40,000 6 $20,000 4 2 Base case AFD on High efficiency AFD on High efficiency both chillers both chillers one chiller one chiller Chiller plant operating cost Simple payback
  56. 56. Dry climate witheconomizer Annual operating cost Simple payback $100,000 18 16 $80,000 14 12 $60,000 10 8 $40,000 6 4 $20,000 2 0 Base case AFD on High efficiency AFD on High efficiency both chillers both chillers one chiller one chiller Chiller plant operating cost Simple payback
  57. 57. Rule 2 Model ROI of each investment
  58. 58. Guidance:VSD or High Efficiency? High efficiency  VSD  Significant demand  Many hours at low charges, especially condenser water ratchet charges temperature – and low load  Climates where the wet bulb doesn’t vary  Perhaps only on one substantially chiller  Multiple chillers in the  Factor replacement plant cost of VSD when performing life cycle  Economizer that assessment reduces low load/low lift operating hours
  59. 59. High PerformanceChilled Water Plants Standard high performance  Reduced flow rates, increased ∆Ts  Variable primary flow Advanced  Equipment capabilities  System configurations  System control
  60. 60. VPF SystemMinimum flow and bypass control  Single chiller  Retrofit Controller P P
  61. 61. What may not be agood VPF application? Two packaged chillers  Limited evaporator configurations  Assume minimum flow is about 1.2 gpm/ton In parallel Wide ∆T (low flow)  e.g 18°F ∆T is 1.33 gpm/ton Why isn’t it a good application?  Flow can only be turned down 10%
  62. 62. Variable-Volume Pumping System (series chillers) 48.4°FUpstream chiller operating at higher temperature is more efficient 41°F 57°F Bypass alternatives
  63. 63. Series Chillers Manual service bypass
  64. 64. Series ChillerAdvantages Simplifies pumping and  Simple preferential sequencing loading of chillers  No flow rate transitions  Adjust upstream chiller’s setpoint  Makes VPF simple  Upward to unload  Downward to load Upstream chiller operates at elevated temperature  Efficiency increases  Capacity increases  10% or more for absorption
  65. 65. High PerformanceChilled Water Plants Standard high performance  Reduced flow rates, increased ∆Ts  Variable primary flow Advanced  Equipment capabilities  System configurations  System control
  66. 66. ControlNormal PerformanceChilled Water Plant Chilled water distribution pump P at most remote sensor Cooling tower fans  55°F (as cold as possible)  Somewhere else Constant volume condenser water pumps
  67. 67. High Performance Chilled Water Pump ControlCommunicating BAS Pump Pump Speed Valve position Pressure Sensor
  68. 68. pump-pressure optimizationControl Logic90.1-2007 Addendum ak Increase pump static pressure setpoint 75%Position (% open) of critical valve No action 65% Reduce pump static pressure setpoint
  69. 69. High PerformanceChiller-Tower Control Plant Power vs CWS Chillers cannot meet load 1,200.0 Lowest condenser water above this condenser water temperature available from temperature tower at this load and wet-bulb temperature 1,000.0 1,550 tons, 65°F Wet-bulb T t 800.0 1,160 tons, 59°F Wet-bulb Power (kW) T 600.0 730 tons, 54°F Wet-bulb Temperature 400.0 Optimal operation 200.0 0.0 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 Condenser Water Setpoint (°F) Hydeman, et. al. Pacific Gas and Electric. Used with permission.
  70. 70. Cooling tower basicsFan energy consumption% Full load power 100 80 60 40 20 0 0 20 40 60 80 100 % Airflow
  71. 71. cooling tower performance factorsApproach and Wet Bulb 16.0 tower approach, deg 12.0 8.0 100% loadapproach = 9 4.0 50% load approach = 4 0.0 50 60 70 80 ambient wet bulb, °F
  72. 72. simple case: constant water flowOperating Dependencies  Wet bulb  Load  Condenser water  Condenser water temperature temperature  Load  Chiller design  Tower design
  73. 73. condenser water control“Normal” Setpoint  Hot? e.g., 85°F, minimizes tower energy consumption  Cold? e.g., 55°F, minimizes chiller energy consumption  Optimized?
  74. 74. optimal condenser water controlChiller–Tower Interaction 400 totalenergy consumption, kW 300 chiller optimal 200 control point 100 tower 0 72 74 76 78 80 82 84 condenser water temperature, °F
  75. 75. High PerformanceChiller-Tower Control Braun, Diderrich Hydeman, Gillespie, Kammerud Schwedler, ASHRAE Journal Cascia Crowther and Furlong
  76. 76. chiller–tower optimizationAn Example …  720,000 ft² hotel  2 chillers, 2 tower cells  Control strategies  Make leaving-tower water cold as possible (55F)  Optimize system operation  Entering-condenser setpoint equals design … 85°F for humid climates 80°F for dry climates
  77. 77. chiller–tower control strategies North America 350K control strategy:annual operating cost, $ USD 300K 55°F lvg tower optimal control 250K design ECWT 200K 150K 100K 50K 0 Mexico City Orlando San Diego Toronto
  78. 78. chiller–tower control strategies Global Locations 500K control strategy:annual operating cost, $ USD 55°F lvg tower optimal control 400K design ECWT 300K 200K 100K 0 Dubai Paris Sao Paulo Singapore
  79. 79. operating cost savings, % 0 2 4 6 8 10 12 Dubai 14 Paris Sao Paulo Singapore Mexico Citylocation chiller–tower optimization Orlando San Diego Operating Cost Savings Toronto
  80. 80. chiller–tower optimizationPerspective on SavingsFor centrifugal chillers ≥ 300 tons, ASHRAE90.1 requires …  0.576 kW/ton at full load  0.549 kW/ton at IPLV… using ARI standard rating conditions
  81. 81. chiller–tower optimization Perspective on Savings EquivalentSavings, % chiller efficiency 0.0 0.576 2.8 0.560 4.5 0.550 6.2 0.540 14.0 0.495
  82. 82. Where’s the Meter? On the BUILDING
  83. 83. chiller–tower optimizationFinding “Near Optimal” Tower design (flow rate, range, approach) Chiller design  Refrigeration cycle (vapor compression vs. absorption)  Compressor type  Capacity control (variable-speed drive) Changing conditions (chiller load, ambient wet bulb)
  84. 84. chiller–tower optimizationNecessities  System-level controls  Variable-frequency drive on tower fans  High-quality dewpoint sensor
  85. 85. Number of chillersoperating Operate one at nearly full load or two at part load? Examine IPLV assumptions
  86. 86. VSDs and centrifugal chillersA Closer Look at IPLVLoad Weighting ECWT kW/Ton100% 0.01 85°F 0.572 75% 0.42 75°F 0.420 50% 0.45 65°F 0.308 25% 0.12 65°F 0.372VSDs improve part-lift performance, so running two chillerswith VSDs at part load seems more efficient than one chiller atdouble the same load, but …is dependent on condenser watertemperature
  87. 87. Chiller power only 45% Plant load Operate 1 or 2 Chillers? Chiller kW Only 350 1@90% Load 300 2@45% Load 250Chiller kW 200 150 100 50 0 55 60 65 70 75 80 85 Available Tower Water Temperature (ºF)
  88. 88. Chillers plus pumps 45% Plant load Operate 1 or 2 Chillers? Chiller Plus Pump kW 400 1@90% Load 350Chiller Plus Pump kW 2@45% Load 300 250 200 150 100 50 0 55 60 65 70 75 80 85 Available Tower Water Temperature (ºF)
  89. 89. Operate 1 or 2 chillers? Run 1 or 2 VSD Chillers? 400 1@90% Load 350 2@45% Load 1@80% Load Operate multiple chillers here, 300 2@40% LoadTotal Chiller Plus Pump kW otherwise single chiller 1@70% Load 250 2@35% Load 1@60% Load 200 2@30% Load 1@50% Load 150 2@25% Load 100 50 0 60 65 70 75 80 85 Available Tower Water Temperature (ºF)
  90. 90. Operate 1 or 2 chillers? 45% plant load: One chiller until tower temperature is < 65°F 40% plant load: One chiller until tower temperature is < 60°F 35% plant load and below: One chiller
  91. 91. High PerformanceCondenser Water PumpControl – Variable? Pump speed limits  Tower static lift  Tower nozzles (minimum flow)  Condenser minimum flow Pump speed reductions result in  Increased leaving condenser water temperature  Decreased cooling tower effectiveness  Possible chiller surge
  92. 92. High PerformanceCondenser Water PumpControl – Variable? The condenser water pump is the hardest place to properly utilize a variable frequency drive during operation There are successful installations
  93. 93. variable-flow condenser waterPump Speed Determining minimum speed Variable flow affects:  Pump  Cooling tower  Chiller
  94. 94. condenser water pumpMinimum SpeedDeterminants: Minimum condenser flow Tower static lift Minimum tower flow  Nozzle selection  Performance
  95. 95. reducing flow & fan speed Effect on System fan speed 300 250system power, kW 200 150 conditions: 100 • 70% load • 50°F WB 50 0 50 60 70 80 90 100 condenser water flow, %
  96. 96. Varying fan and pumpspeed together
  97. 97. variable condenser water flowGuidance Can provide savings …  Finding proper operating points requires more time, more fine-tuning Two-step process: 1 Reduce design pump power 2 Is variable condenser-water flow still warranted?
  98. 98. ROIHigh PerformanceChilled Water Plants EnergyPlus Non-bin Schematic tools that analyze in 30- 45 minutes are available
  99. 99. High PerformanceChilled Water Plants Standard high performance  Reduced flow rates, increased ∆Ts  Variable primary flow Advanced high performance  Equipment capabilities  System configurations  System control
  100. 100. High performance chilled water plantWinchester MedicalCenter
  101. 101. Medical CenterWinchester, Virginia Five 750-ton chillers  VFD’s on  0.571 kW/ton full load  Chilled water pumps  Chilled water  Cooling tower fans 58 to 42°F  Condenser water  Condenser water pumps 84 to 95°F (missed opportunity)  Sophisticated control system with lots of  VFD’s  Programming Variable primary flow  Commissioning
  102. 102.  Owner Center  Operators  Service provider  Working together  Controls provider  Equipment provider  Consulting engineer Load (tons) 8/ 8/ 2 8/ 00 3 8/2 1 4 0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 1400.0 8/8 00 3 :30 /2 1 3 8/ 00 3 :30 8/ 2 12 8/ 00 3 :30 8/2 1 0 1:3 Applications engineering 8/8 0 3 1 0 /2 0:3 8/ 00 3 0 8/ 20 9 :3 8/ 0 3 0 8/2 8 :3 8/8 00 3 0 /2 7 :3 8/ 00 3 0 8/ 2 6 :3 8/8 00 3 0 /2 5 :3 8/8 00 3 0 /2 4 :3 8/ 00 3 0 8/ 2 3 :3 8/8 00 3 0 /2 2 :3 8/8 00 3 0 / 1 8/ 200 :3 0 Time/Date 7/2 3 0 8/7 00 3 :3 0 /2 2 3 8/ 00 3 :30 7/ 20 2 2 8/ 0 3 :30 7/2 2 1 8/7 00 3 :30 /2 2 0 0 8/ 0 3 :30 7/ 2 19 8/7 00 3 :30 /2 1 8 8/7 00 3 :30 /2 17 Winchester Medical 8/ 00 3 :30 7/ 20 1 6 0 3 :30 15 :3 0 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 Efficiency (kW/ton) tons kW/ton
  103. 103. Load (tons) 8/ 8/ 2 8/ 00 3 8/ 2 14 0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 8/ 00 3 :30 8/ 1400.0 2 13 8/ 00 3 :30 8/ 2 12 8/ 00 3 :30 8/ 20 1 1 0 : 8/ 3 1 30 8/ 2 0: 8/ 00 3 30 8/ 20 9 :3 8/ 0 3 0 8/ 2 8 :3 8/ 00 3 0 8/ 2 7 :3 8/ 00 3 0 8/ 2 6 :3 8/ 00 3 0 8/ 2 5 :3 8/ 00 3 0 8/ 2 4 :3 8/ 00 3 0 8/ 2 3 :3 Chiller plant 8/ 00 3 0 8/ 2 2 :3 8/ 00 3 0 8/ 1 8/ 200 :3 0Time/Date 7/ 2 3 0 8/ 00 3 :3 0 7/ 2 23 8/ 00 3 :30 7/ 2 22 8/ 00 3 :30 7/ 2 21 8/ 00 3 :30 7/ WMC - August 12 2 20 8/ 00 3 :30 7/ 2 19 8/ 00 3 :30 7/ 2 18 8/ 00 3 :30 7/ 2 17 8/ 00 3 :30 7/ 20 1 6 0 3 :30 15 :3 0 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 Efficiency (kW/ton) tons kW/ton
  104. 104. Tons 0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 1400.0 1600.0 1/0/1900 0:00 1/0/1900 0:00 1/0/1900 0:00 1/0/1900 0:00 1/0/1900 0:00 9/1/2003 14:00 9/1/2003 19:30 9/2/2003 1:00 9/2/2003 6:30 9/2/2003 12:00 9/2/2003 17:30 9/2/2003 23:00 9/3/2003 4:30 Chiller plant 9/3/2003 10:00 9/3/2003 15:30 9/3/2003 21:00Time 9/4/2003 2:30 9/4/2003 8:00 WMC - Sept 1-7 9/4/2003 13:30 9/4/2003 19:00 Weekly-Summary 9/5/2003 0:30 9/5/2003 6:00 9/5/2003 11:30 9/5/2003 17:00 9/5/2003 22:30 9/6/2003 4:00 9/6/2003 9:30 9/6/2003 15:00 9/6/2003 20:30 9/7/2003 2:00 9/7/2003 7:30 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 kW/ton tons kW/ton
  105. 105. Winchester MedicalCenter - Mark Baker  “Please use our data, names, etc. Were proud of our facility!”  “By the way, were now operating @ -0.20 kW/ton. The power company just sent us our 1st check. Ha..Ha…”
  106. 106. Remember... Without controls, it’s not a system.
  107. 107. The meter is on thebuilding!
  108. 108. It’s a great time tobe in this business!

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