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UCSD Medical Center - Hillcrest Campus Case Study. Gerry White Facilities Design & Construction University of California, San Diego. UCSD Medical Center. Former county hospital which became part of UCSD in the late 1960s 17 buildings of varying age 870,000 square feet total
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UCSD Medical Center - Hillcrest CampusCase Study Gerry White Facilities Design & Construction University of California, San Diego
UCSD Medical Center • Former county hospital which became part of UCSD in the late 1960s • 17 buildings of varying age • 870,000 square feet total • 490,000 square feet in main hospital
UCSD Medical CenterOriginal HVAC Equipment • Four chillers, 2380 tons capacity • Two 760 ton centrifugal chillers, 1975, R-11 • 160 ton air cooled unit, 1982, R-22 • 700 ton 2-stage absorption unit, 1991 • Three cooling towers • Primary chilled water distribution system • Four boilers • 3 can only operate at 60% of rated capacity • Unreliable and unsafe
High utility costs Consumed ~31 million kWh/year and 1.5 million therms, $2.8 million per year Lack of sufficient cooling capacity to meet load requirements Unreliable and unsafe boilers working at low capacity Unused thermal storage facility UCSD Medical CenterProject Scenario
UCSD Medical CenterMajor Project Challenges • Selling project and finding financing • hospital finances very tight • project had to pay for itself • Keeping hospital operational • night and off-hour work • use of temporary chillers • transition from old to new controls
UCSD Medical CenterProject Solutions • Load reductions • Distribution system improvements • New central plant equipment • New control system • Recommissioned systems
UCSD Medical CenterLoad Reductions • Lighting improvements coincident with project • High efficiency T-8 lamps with electronic ballasts • Changed over 15,000 fixtures • Light levels maintained • Reactivated an old, unused thermal energy storage system • 3,500 ton/hr system • 500 tons cooling capacity
UCSD Medical CenterDistribution System Improvements • Air handling unit replacement • replaced several selected supply and exhaust units • Replaced AHU components • cooling coils & control valves • Chilled water system • converted to primary/secondary • changed to 2-way valves
UCSD Medical CenterCentral Plant Equipment • Removed two oldest R-11 760 ton chillers • installed two new 750 ton R-123 chillers • Removed 3 older boilers • replaced with 2 new low NOx dual fuel boilers • Upgraded all chilled water and steam system plant auxillary systems
UCSD Medical CenterControl Systems & Commissioning • Upgraded entire control system to direct digital control • Energy conservation strategies implemented • night-time AHU discharge temperature resets • discriminator controls set discharge temperatures to meet worst zone conditions • Recommissioned all HVAC systems and steam distribution system
UCSD Medical CenterFinancing Structure • University financed for a 10-year term • Low interest rate (7.75%) on external financing • Tax-exempt financing • Positive cash flow of ~ $400,000 annually • ~ $1,300,000 annual energy and O&M savings • ~ $900,000 annual loan payment
UCSD Medical CenterProject Timeline 28 months to complete project
UCSD Medical CenterProject Results • 10 million kWh/year reduction in electricity usage for the complex (30%) • Cooling load reduced 500 tons (17%) • Gas consumption down 600,000 therms/yr (40%) • Utility savings of $950,000 annually (33%) • Maintenance savings of $340,000 annually • Improved building comfort from better balancing • Better system reliability and controllability