Technical And Financial Benefits Of Retro-Commissioning Initiatives Society of American Military Engineers Northern Virginia Post January 6, 2011 Presented By: Robert S. Bucey, PE, CEM, LEED AP

What is Retro-Commissioning?  Systematic investigation process for improving and optimizing the operation and maintenance of buildings  Primarily focuses on energy-using equipment and low-cost improvements rather than expensive capital-intensive retrofit measures  Involves detailed study of building system operation  Faults in building systems are identified for resolution  Control changes may be recommended that increase energy efficiency  Economic analysis that calculates energy savings  Follow-up required to verify that measures have been correctly implemented and have held up over time  Can resolve problems that occurred during design or construction, or that have developed throughout the building’s life

“Have you seen this?”

Why Retro-Commission Now?  Occupant comfort:  Indoor air quality concerns  Reduce employee absenteeism  Reduce tenant turnover  Improve employee productivity  Improve thermal comfort  Protect or enhance property condition:  Protect against future liability  Increased asset value of income-producing properties  Fewer warranty claims

Why Retro-Commission Now?  Improved operation:  Reduced maintenance calls  Train building technicians on RCx process  Create system-level benchmark to facilitate efficient monitoring of systems  Provide single document resource for O&M staff  Reduce operating cost / energy consumption:  Problems never identified during initial building start-up  Systematic problems in building operation  Environmental problems  Excessive equipment run times due to changes in occupancy or space use  Malfunctioning equipment or sensors  Control optimization issues  Extend equipment life

Why Retro-Commission Now? Cost avoidance !!!!!!

Basic Steps In The RCx Process  Document review  Building walk through  Organize utility data history  Assess BAS and control system effectiveness  Develop detailed work plan  Establish current system performance  Develop and implement functional performance test procedures  Operator training program  RCx manual, lessons learned and future RCx initiatives

Retro-Commissioning Process  Planning  Select facility – prioritize groups of buildings  Identify project objective (Performance/Energy/Both)  Document performance requirements  Perform initial site walk-through  Establish energy benchmark  Identify potential energy conservation measures  Develop detailed work plan  Assemble team & define responsibilities

Retro-Commissioning Process

 Investigation  Detailed review available documentation  Diagnostic monitoring of building automation system  Conduct functional performance testing  Make “simple” modifications/repairs  Document results  Make recommendations for improvement  Major repairs/modifications  Update energy conservation measures

Retro-Commissioning Process Fig. 1 Temperature data logger deployed Fig. 2 Power data logger deployed Fig. 3 Sample BAS Diaplay Fig. 4 Occupancy and photo sensor results for Operating Room

Retro-Commissioning Process

 Turnover  Develop scope of work documentation for improvements  Provide operator training  Compile retro-commissioning manual  Share lessons learned  Develop ongoing commissioning plan

Where are the RCx Opportunities? (Examples)  Simultaneous heating and cooling  BAS programming vs. actual operation  Correct and most efficient air damper sequencing  Chilled water bypasses and leaks  Corroded condenser coils  Incorrect head pressure control and hot gas bypass connections  Poor equipment access  Equipment not responding to control system  Temperature and humidity sensors out of calibration  Control sequence not operating correctly  Electric duct heaters with incorrect wiring  Incorrect cooling load calculations

Some RCx Lessons Learned  Inadequate building documentation  Access to building automation system data  Systems “never ran right from day one”  Zone level adjustments made but never tracked  Changes made during construction  “Improving Performance” may not always reduce energy consumption  Set expectations up front  Need buy in from all parties!

Industry Results  Our experience: 15% to 25% savings in energy alone  GSA ARRA Program: Identified 2,794 energy conservation measures in 50 buildings  Study of 643 buildings: over 10,000 energy-related problems, resulting in 16% median whole-building energy savings, with payback of 1.1 years

Industry Results TargetLocationEnergy savingsProject cost ($/sf)Payback time (years) Local government buildings California14.3% source energy, 11% electricity, 34% gas Class A officesConnecticut7.3% electricity Mixed commercialColorado7% electricity University buildings California10% total source SupermarketsCentral California12.1% electricity Mixed commercialOregon10-15% electricity Mixed commercial and educational California % electricity Source: Evan Mills. 2009, "Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse- gas Emissions"

Industry Results Number of measures applied Type of deficiency solution Source: Evan Mills. 2009, "Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse- gas Emissions"

1 ROI Expectations Source: Evan Mills. 2009, "Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse- gas Emissions"

1 ROI Expectations Source: Evan Mills. 2009, "Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse- gas Emissions"

Options To Implement An RCx Program  As an element of an overall energy plan  Coordinate with predictive maintenance, facility condition assessments, capital R&R planning  Combine with overall strategy to reduce deferred maintenance  Seed program with annual funding to implement “low hanging fruit” initiatives; invest savings in further energy conservation measure implementation  Canvas available rebates and invest in ECM implementation  Energy services contract vehicle

Questions Thank you for your attention