St. Mark’s Hospital – Salt Lake City, Utah


Strategic Energy Management / Re-commissioning


Solarc Energy Group led this comprehensive Strategic Energy Management (SEM) effort that reduced overall energy use by 10% and markedly improved patient comfort.  This team effort involved Solarc’s on-site experts, Rocky Mountain Power’s SEM team, and the hospital’s internal facilities staff.  Work focused on operating improvements to the hospital’s mechanical and electrical systems in a comprehensive and systematic way.  SEM duration was 18 months, starting with a detailed diagnostics effort and concluding with a final savings verification and persistence planning effort.


Project Summary


Hospital size:  517,600 sq.ft.

Verified annual electric energy savings: 1,400,000 kWh

Annual electric cost savings: $112,000

Percentage electrical use reduction: 7.8%

Utility incentive: $28,000

External implementation cost (controls work): $10,000


SEM Measures Implemented to Save Energy


  • Occupant education and training
  • De-lamp 3-lamp and 4-lamp fixtures
  • Scheduling of VAV terminal units
  • Increase chilled water enable setpoint
  • Aggressive supply air temperature reset
  • Optimize condenser water setpoint
  • Optimize chilled water reset schedule
  • Heating water pump optimization
  • Optimize economizer high limit setpoint
  • Reduce duct static pressures and inspect/optimize sensor locations
  • Scheduling of air handlers
  • Schedule exterior fountains both seasonally and at night
  • Review and optimize operation of parking garage ventilation system
  • Drop steam pressure setpoint by another 5-10 PSIG
  • Optimize blow-down practices
  • Drop minimum humidity target to 20%
  • Reduce ductwork leakage
  • Mixed air temperature control optimization
  • Optimize primary-secondary chilled water pump and minimize bridge mixing
  • Test, repair, and replace leaking hot water valves
  • Re-commission stack economizer on boilers


Non-Energy Benefits


  • Patient comfort satisfaction increased according to hospital surveys
  • Hot/cold calls decreased allowing the maintenance staff to redirect their focus