SCC C l t A l iSCC Complete Analysis:SF1-3SF13AHU-X4sHot Water LoopHot Water LoopBuilding Gas ConsumptionGroup 2Emily Hedges, Chris Light, and Lianne WilliamsCEE243Hedges, Light, Williams Stanford University - CEE243 1CEE243June 2, 2010Intro• Analysis shows potential for energy savings•Utilized systems approach broken down by spaces served•Utilized systems approach broken down by spaces served– Looked for patterns between complimentary data points; i.e. supply air temperature, space air temperature, heat/cool coil valve positions and outside air temperaturepositions and outside air temperature– Time series were predominantly used; zooming to look closer at anomalies–Patterns of interest are called out with a dashed box/circlePatterns of interest are called out with a dashed box/circle– Traffic lights assigned on a whole system level •Assigned systems:Assigned systems: – SF1, SF2, SF3– AH44, AH54, AH64, AH74, AH84–Hot Water LoopHedges, Light, Williams Stanford University - CEE243 2–Hot Water Loop– Building Gas ConsumptionSupply Fans 1-3SET POINT:• Zones 1-4: 66°F72°F66°F -72°F•Zones 5-6: 66°F - 70°F• Supply fan & Return fan: Always OnHt•Heat Exchanger: On when OAT <52°F or >76°FThe thickness of the red band represents the energy in the system—the band thickens when energyHedges, Light, Williams Stanford University - CEE243 3thickens when energy is added, and it thins whenever energy is removed.Supply Fans 1-3SF Light Reason-Space air temperature primarily within 72°F±1°FC li /h ti il iti fl t t i ifi tl &1Red-Cooling/heating coil position fluctuates significantly & almost instantaneously-Huge variation in supply air temperatureSpace air temperature primarily within 73°F±3°F2 Yellow-Space air temperature primarily within 73F±3F-Zone 5 shows significant cooling, but also has highest average temperatures -Only discrete heating/cooling coil valve positions are yggpobserved (0%, 50%, and 100%)-Supply air temperature not available-Space air temperature primarily within 73°F±3°F3 Yellow-Only discrete heating/cooling coil valve positions are observed from data (0%, 50%, and 100%)-Inconsistent control schemes among zonesSlit t t ilblHedges, Light, Williams Stanford University - CEE243 4-Supply air temperature not availableAir Handling Unit 44, 54, 64,74, 84LbbSET POINT:• 74°F ± 2°FSlfLobbyCore•Supply fan, return fan, and outside air damper palways OnThe thickness of the red band represents the energy in the system—the band thickens when energy is added and it thinsHedges, Light, Williams Stanford University - CEE243 5is added, and it thins whenever energy is removed.AH747hFloor Core/Lobby/SystemDevice Point Type ID Source Units Set Point Notes/ProblemsCore SpaceSpaceAir Temperature113 Sensor °F74°F ± 2°F (SCC Spec Doc )MySQL database lists source as “Control”Temperature(SCC Spec. Doc.)CoreCooling CoilValvePosition 114 Control %Assume 0% indicates no cooling and 100% full coolingLobby SpaceSpaceAir Temperature116 Sensor °F74°F ± 2°F (SCC Spec. Doc.)epeatue(p )LobbyHeat/CoolCoilCombinedValve Position117 Control % 0% indicates heating; 50% indicates neither heating nor cooling; 100% indicates cooling (SCC Data Manual)System AH44MixedAir Temperature115 Sensor °FTemperatureSystemOutsideAir DamperDamper Position291 Control %Fixed On (SCC Spec. Doc.)Assume 0% indicates closed and 100% indicates fully openSystemSupplyFan44On/OffStatus 290 SensorBinFixed On (SCC Spec. Doc.)Does not always output as binary; Assume 1 is on and 0 is off(p )SystemReturnFan44On/OffStatus 292 SensorBinFixed On (SCC Spec. Doc.)Does not always output as binary; Assume 1 is on and 0 is offHedges, Light, Williams Stanford University - CEE243 6AH74 - LOBBY%)(A)Intended Set Point:74±2°Fure (°F )ve Position (%Cooling()Point: 74 ±2°F Temperatug/Cooling Valving50%neither(B)HeatingHeati(C)Date/Time• Yearly variation in space air temperature: 69°F to 78°FHedges, Light, Williams Stanford University - CEE243 7• (B): indicates region of more frequent cooling in October/November than occurred in the summerAH74 - LOBBYion (%)ingerature (°F )Intended Set Point: 74 ± 2 °F g Valve PositiCool50%neitherTempeHeating/CoolinHeatingTime on 11/13/2009Herature (°F )ooling Valve on (%)(A)Intended Set • Inconsistency: Heating and cooling cycles in November with constant OAT• Hypothesis: Set points actually set to heat below 69°Fd lb 74°Fthi b d b tHedges, Light, Williams Stanford University - CEE243 8TempeHeating/CoPositio(B)(C)Point: 74 ± 2 °F69°F and cool above 74°F; this band may be too narrow, causing oversensitive heat/cool responseAH74 - CORE(B)Intended Set Point: 74 ± 2 °F ture (°F )Position (%)Temperatooling Valve P(C)(A)Co(C)Date/Time• Yearly variation in space air temperature: 63°F to 80°FHedges, Light, Williams Stanford University - CEE243 9• (B): Unusual spikes in space temperature to 80°F in January 2010AH74 - CORE%)Intended Set Point: 74 ± 2 °F perature (°F )alve Position (%TempCooling Va1/6/101/5/10°erature (°F )Valve Position (%)(A)(B)• Inconsistency: Core cools above 74°F; spikes in space air temperature in middle of the night in January instigate cooling and do not correspond to OATHhiOtiltiHedges, Light, Williams Stanford University - CEE243 10TempeIntended Set Point: 74 ± 2 °FCooling (C)(A)•Hypothesis: Occupancy, space use, or ventilation changes could be cause of spikesAHUs X4sAHULightReasonAHULightReason44 Yellow-Space air temperature data may not correctly correspond to spaces listed for AHU 44-Some heating and/or cooling occurs out of season54Yellow- Core and lobby exceed assumed set point-Observed set point band of 69°Fto74°F54YellowObserved set point band of 69F to 74F- Heat/cool at unexpected time of day/year and OAT64Red- Core and lobby space experience 11°F of variationOb d t i t b d f 72°Ft 74°Fi l bb64Red-Observed set point band of 72°F to 74°F in lobby space seems to cause cyclical heating and cooling 74Rd- Core and lobby space experience 17°F of variation74Red- Observed set point band of 69°F to 74°F in lobby space seems to cause cyclical heating and cooling- Core and lobby exceed assumed set pointHedges, Light, Williams Stanford University - CEE243 1184 Yellow-Observed set point band of 69°F to 74°F- Heat/cool at unexpected time ofday/year and OATHot Water LoopBoilers reheat return water and mix with make up watermake up water from tank 2Pumps 9 & 10