UCSF Mission Bay Campus Arthur and Toni Rembe Rock Hall th Street San Francisco, California

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1 UCSF Mission Bay Campus Arthur and Toni Rembe Rock Hall th Street San Francisco, California Monitoring Based Recommissioning Project Project Implementation: June 2005 to December 2005 Funded by a grant from PG&E (under the UC / CSU / IOU Partnership Program) UCSF Rock Hall Building Occupancy Date: February 2004 Building GSF: 176,000 Building Type: Research Laboratory Baseline Utility Consumption (0/04 02/05): Electricity: 8,441,600 H/year Peak Demand: 1781 atural Gas: 450,09 Therms/year Specific Energy Consumption Peak Watts/GSF: 10.1 Annual H/GSF: 48.0 Annual Therms/GSF: 2.56 Electrical ALF 0.54 UC/CSU/IOU Partnership Energy Efficiency Grant Program: Project Highlights Initial/Perceived Deficiencies: Variable volume air handlers essentially operating at constant flow, excessive chiller cycling and loading, insufficient meters and instrumentation within basic system, existing instruments not functioning and/or out of calibration. Program Premise: Significant energy savings are achievable in existing buildings through retrocommissioning and by providing additional metering/monitoring to facilitate improved building performance. Project Funding: $270,000 Proposed Energy Savings Target: 409,260 KWH & 47 KW & 1,100 Therms Required Project Completion Date: December 1, 2005 Actual Energy Savings Harvested: 720,08 KWH & 7 KW & 76,987 Therms 1

2 Measures Implemented 1. Programmed night setback airflows at zone terminal boxes 2. Revised room level airflow set points at terminal boxes served by air handlers. Calibrated required static pressure setpoints within airside and waterside systems. 4. Calibrated and/or replaced temperature and pressure sensors within CHW and HW Systems. 5. Installed Flow meters at steam, heating & domestic hot water systems 6. Installed Flow meter & bypass valve at chilled water system Cleaver Brooks 400 HP 16,29,000 BTU atural Gas fired Boiler Cleaver Brooks CB Hawk Controller 80 psi to 5 psi Steam pressure reducing station Boiler atural Gas meter Gas Meter amplifiers 80 psi Steam flow meter to 5 psi pressure reducing station 80 psi Steam flow meter to East equipment on 2 nd & 4 th fl. Chilled Water Pressure Transducer Condenser Water Pressure Transducer 2

3 EQUIPMET/STATEPOITS METERED I.D. Type Volts Phase HP VFD Unit Interval Meter P01 CW Pump 25 P02 CW Pump 25 P0 CW Pump 25 P04 CW Pump 25 P05 CHW Pump 40 P06 CHW Pump 40 P07 CHW Pump 40 P08 HHW Pump 20 P09 HHW Pump 20 P10 HHW Pump 20 CH01 Chiller ~220 CH02 Chiller ~220 CH0 Chiller ~220 CT01 Tower Fan 20 CT02 Tower Fan 20 CT0 Tower Fan 20 AHU01 Supply Fan 75 AHU02 Supply Fan 75 AHU0 Supply Fan 100 AHU04 Supply Fan 100 AHU05 Supply Fan 150 AHU06 Supply Fan 150 OAT Temperature F Hobo OA RH R. Humidity RH Hobo MEASURES 1&2: AIR HADLIG SSTEM Categories For Airflow Modifications: Minimum airflow setpoints high. Airflow for future equipment incorporated where equipment was not actually installed. Introduced variable air volume in certain boxes previously balanced as constant air volume. Additional Items Implemented: ight setback airflows introduced. Static pressure setpoints verified and revised with aid of air balancing contractor. Building exhaust fans also had static pressure revisions. Reduced flow at exhaust fans by introducing better seals at rooftop exhaust fans (preventing reverse flow) thus reducing fan energy consumption. AHU AHU Comparison (Baseline And Post Improvement) y = x y = x AHU Comparison (Energy Reduction) The average temperatures were 57 deg F for both the days. Baseline : 22 August and Post Improvement: ovember, OA Temp (degf) Post Improvement Baseline Linear (Best Fit Lines)

4 Measures,4&5: Calibration/Replacement Of Existing Sensors Air Handling Units and Exhaust Fans static pressure setpoints adjusted and sensors calibrated. Chilled water flow through chillers calibrated flow adjusted. Chilled water/heating water pumps pressure sensors replaced with diaphragm double ended Serta Type DP transducers, pressure gages also installed. Adjusted AHU5 heating hot water valve that was not closing causing chilled water valve to open. Added steam flow meters and heating and domestic water flow meters. Calibration/Replacement Of Existing Chilled Water System Sensors CHW PUMP (200 AUG) Pre Project Post Project DATE/TIME CHW PUMP (200 AUG) CHW Pump operation Aug 200 Measure 6: Chilled Water Remote Bypass Initial issue chiller cycling too much, especially at low loads. Chilled water bypass valve necessary to ensure minimum flow through primaryonly loop variable frequency drive chiller. Owner requested to move location of bypass from chiller room to remote location (end of loop at roof location). Added magnetic type flow meter at bypass leg, to ensure consistent measurable minimum flow of chilled water necessary for primaryonly loop system. Programmed free cooling sequence into chilled water system by opening air handling unit chilled water valves during nighttime/low loads with pumps running without chiller. 4

5 Free Cooling Most common on airside as an economizer cycle. Waterside economizer typically includes running cooling towers and using condenser water as cooling source for air handling coils. This application does not include the use of cooling towers. Instead, water within the chilled water loop is run to the outside and aircooled at air handling unit coils by keeping the chilled water coils open. Generally this has allowed for chillers to remain off during nighttime hours while cooling electrical room fan coil units with constant heat loads. Chilled Water System Baseline Versus Post Improvement The chilled water system assessed includes the chillers and the CHW pumps. The average temperatures were 57 degf for both the days. Baseline : 22 August and Post Improvement: ovember, During the post improvement monitoring while the outdoor air temperature was below 58 F, the chillers and chilled water pumps were not running. y = x y = x Outside Air Temperature (OAT) in deg F Post Improvement Baseline Post Improvement (o Load) Linear (Best Fit Lines) Monthly Gas Consumption (Measures Implemented In SepOct 2005) atural Gas consumption (Therm) 50,000 45,000 40,000 5,000 0,000 Therm 25,000 20,000 15,000 10,000 5,000 0 Average OAT July (65F) August (67F) Sept (68F) October (61F) ovember (55F) December (52F) January (50F) February (55F) March (58F) April (57F) May (62F) June (62F) July (65F) August (64F) September (6F) October (62F) ovember (58F) December (5F) January (52F) February (5F)

6 Monthly Gas Consumption (Measures Implemented In SepOct 2005) Utility Data Comparison (Post and Pre MBCx) Month 50,000 45,000 40,000 5,000 0,000 25,000 20,000 68F 6F 61F 62F 55F 58F 52F 5F 50F 52F 55F 5F 15,000 10,000 5,000 0 Sept October ovember December Jan Feb atural Gas (Therm) (Sep 2004 thru Jan 2005, versus Sep 2005 thru Jan 2006) Pre MBCx Post MBCx Building Hvac Energy Use Distribution Before Retrocommissioning (Baseline) and After Measures Were Implemented HVAC Equipment electric consumption (Baseline) HVAC equipment electric consumption (Post Improvement) HHWP h 0% CHWP h 4% CWP h 4% CT h 1% HHWP h 1% CWP h 7% CT h 1% CHWP h 2% CH h 18% CH h 18% AHU h 71% AHU h 7% Hvac Equipment Energy Consumption Summary Equipment h comparison to Total h AHU 1h AHU 2h AHU AHU 4h AHU 5h AHU 6h CH1h CH2h CHh CHWP5h CHWP6h CHWP7h HWP8h HWP9h HWP10h CWP1h CWP2h CWPh CWP4h CTF2 h CTF h Total h Equipment Post Improvement Baseline 6

7 Energy Savings Breakdown Electricity Consumption: Air handler fan energy Exhaust fan energy reduction Chiller energy reduction Chilled water pump energy reduction Total: 77,864 H 280,20 H 8,784 H 5,070 H 720,08 H Electricity Demand: Air handler fan energy Exhaust fan energy reduction Total: Energy Savings Summary Project Targets: Electric Consumption Savings h 409,260 h Electric Demand Savings 47 Therm Savings 1,100 Therms Actual Harvested: Electric Consumption Savings h Electric Demand Savings Therm Savings Percentage of Total Electric Consumption Saving Over Target Percentage of Total Electric Demand Saving Over Target Percentage of Total Therm Saving Over Target 720,08 h 7 76,987 Therms 176% 155% 588% Financial Considerations Annual Electrical Utility Charge 11 cents/h: $79,204 Annual atural Gas Utility Charge $1/Therm: $76,987 Total Annual Savings: $156,191 Simple Payback Period for $270,000 grant: 1.7 years Estimated 20year value of savings in current dollars: $.12 Million. 7

8 Questions? 2 5 psi Steam to Water semi instantaneous water heaters 25 GPM each EWT 40 F, LWT 140 F 2400 PPH Steam each City Water Make up Temperature Sensors Domestic Hot Water Return 5 psi Steam to Water Heating Hot Water System 0 GPM 140 F EWT 180 F LWT 6,860 PPH Steam@ 0 PSI VFD s for pump motors HHW Pumps 20 HP motor Rated 50 Head 8

9 Variable Primary Chilled Water System 50 Ton 167 Trane Centrifugal Chillers Chilled Water Pressure Transducer Condenser Water Pressure Transducer Chilled Water Manual Bypass Valve Chiller CHW Isolation Valves CHW Flow Sensor 9

10 Chilled Water Valve 40 HP 812 GPM Chiller Water Pumps VFD s for CHW Pump Motors Water Roof top Chilled Bypass 10

11 Rooftop General Exhaust ACF EF 4 & 5 Exhaust Air Dilution Damper Roof top Exhaust Air Dampers Exhaust Fan Isolation Damper 11

12 General Exhaust Air Dilution Damper Supply Air Handler averaging air temperature sensor The Team UCOP Project Manager: Maric Munn, PE UCSF Project Manager: Jeff Hughes, PE UCSF Project Director: Sukhi Sandhu, PE UCSF Building Chief Engineer: Bruno Cekovic Building Engineers involved: Frank Plut & Ronny Melo Engineering Consultant/Commissioning Agent: Raj Daswani, PE (ARUP) Controls Contractor: amas, Inc. PG&E Project Manager: Mark Bramfitt Rock Hall Atrium 12

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