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Saving Millions ($) Through RCx!
Armando J. de LeónUtilities EngineerVA State Corporation Commission
James D. Mascaro, PE, CCPVice PresidentDirector of Commissioning Services
AIA Quality Assurance
The Building Commissioning Association is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of the Completion for both AIA members and non-AIA members are available upon request.
This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.
Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
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At the end of this session participants will be able to:• Gain a Better Understanding of the
Retro-Commissioning Process• Discuss the Benefits of the RCx process• Identify Energy Conservation Measures (ECMs)• Learn how to apply the RCx process to their existing
buildings
Learning Objectives
ASHRAE Standard 202RCx (or Existing Building Commissioning) is a quality-focused process for attaining the Current Facility Requirements (CFR) of an existing facility and its systems and assemblies. The process focuses on planning, investigating, implementing, verifying, and documenting that the facility and/or its systems and assemblies are operated and maintained to meet the CFR, with a program to maintain the enhancements for the remaining life of the facility.
What is Retro-Commissioning (RCx)?
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What is RCx?Thinking you’re driving out of the showroom with….
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• Finding out you got this….
What is RCx?
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• And eventually turns into this…
What is RCx?
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The Process Requires Teamwork
What happens when ONE
team member drops the baton in the
race?
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RCx Process
• The RCx process involves steps that are integrated into your existing building:
• Contract Phase • Pre-Site Investigation Phase• Site Investigation Phase• Problem Analysis Phase• Corrective Action Phase• Follow Up Phase• Training
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• Achieves Energy Savings of 5 - 20% of total building energy costs
• Has a payback from energy savings averaging 2 years or less
• Reduces operating expenses
• Source: PECI
• Case Study from UVA: payback = 7 months to 1.5 years!
RCx Typically…
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Getting Organized
• Select a building • Meet with the RCx team
• Energy Manager• O&M Facility Engineer• Building Representative• Owner’s RCx Project Manager• Consultant RCx PM
• Define RCx goals = Scope• Assemble/Analyze documentation• Facility walk-through• Assessment of systems begins!
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Case Study: University of Virginia
• Interdisciplinary Team
• Facility Coordinators• FM Trades and Staff• External Consultants• Building Occupants
• Led by Sustainability Staff• Retro-Commission Existing Buildings• Reduce Overall Energy and Water use• Promote Sustainable Practices
UVA - Delta Force Team
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• Renovation of Mechanical, Electrical and Plumbing Systems
• Mechanism for addressing a change in the way a building is used
• Directly focused on addressing deferred maintenance
Delta Force Team is not ...
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• Buildings that have been identified as:• Large energy and water usage
• Potential for reductions in:• Electrical Energy• Steam & Medium Temperature Hot Water• Chilled Water• Water and Sewer
• Additional implementation of Recycling, Green Housekeeping, Green Landscaping and Storm-Water Management
• Identify ECMs & Implement Recommendations!
Delta Force Team Focus ...
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• Funded by a $1M revolving line of credit from the Vice President for Management & Budget
• Performance Contract
• Basis for recovery being established
• Provide detailed quarterly reports
• Variation in cost from $1 to $2 per square foot
• Based on age and complexity of building
Cost ...
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West Medical Complex13 Buildings (1927-1984) Approximately 790,000 GSF
• Where are these defined? • OPR? CFR?
• Set up properly?• Improper system programming can lead to occupant
request for modified schedule (i.e. turn on an entire floor vs one AHU)
• Often modified to accommodate specific short-term occupant needs
• Modifications can be forgotten!• 61 AHU’s – chilled water from central chiller plant
Equipment Operating Schedules
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• Original building – 1920’s
• Major renovations/additions: 1960’s – current
• Over 120 major HVAC revisions since 1960’s!
• RCx activities started July 2010
• Initial RCx activities completed June 2011
Old Medical School - Background
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Site Investigation Ph. - Sample Issue
UVA Multistory Building
VFD running in “hand” mode.
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Site Investigation Ph. - Sample Issue
Triple duty valve: 20% open!
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Site Investigation Ph. - Sample IssueCW valve pneumatic tubing not connected
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Site Investigation Ph. - Sample Issue
AHU pump bypass open due to non-functionality23
Site Investigation - Sample Issue
Damper actuator limited by copper tubing24
Site Investigation - Sample Issue
• Economizer enabled • Heating/Cooling Same Time
• OA adequate to meet building needs
49.9°F
44.8°F
55.9°F
Open
100% Open 48.2% Open
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Original building – 1920’s
Major renovations/additions: 1960’s – current
Over 120 major HVAC revisions since 1960’s!
Initial RCx activities completed June 2011
Initial cost to implement ECMs = $255,698
1st Year Energy Savings = $349,283
Old Medical School - Results
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Multistory Building (approx. 239,600 g.s.f.)
University Energy SavingsGreat Success Story!
September 2009 - RCx Process StartedTotal University Expenses to May 2013: $540,000Total Avoided Costs to May 2013: $1,472,000
Old Medical School (approx. 171,000 g.s.f.)
May 2010 - RCx Process StartedTotal University Expenses to May 2013: $318,000Total Avoided Costs to May 2013: $764,000
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RCx agents recently discovered the operation of the economizer cycle for two large AHU’s had been programmed backwards!
The control sequence had been operating under this condition for over ten years!
The controls were reprogrammed immediately!
News Flash… Economizer Cycle Backwards!
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UVA Single Building Example
July 2009- June 2010
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MTCDE Reduction Results
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Avoided Costs
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Program Avoided Costs ...
Cumulative Avoided
Program Energy (MMBTU)
Carbon (MTCDE) Financial (USD) Financial (USD)
Delta Force 151,420 22,122 4,739,408$ 11,403,422$
Non‐Delta Force Lighting 4,473 1,119 160,265 456,364
Shared Savings 1,296 324 46,424 123,771
Other Projects 2,643 460 85,689 664,917
Interruptable Load (ILR) 147,507$ 603,315$
Total FY2013 159,832 24,025 5,179,292$ 13,251,789$
Current Year Avoided
Energy & Utilities DepartmentEnergy Conservation Projects
Pre-RCx Trending Results
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Post-RCx Trending Results
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Compare Results of RCx Process
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Compare Results of RCx Process
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• Lighting retrofit• Occupancy sensors to operate lights• Add VFDs where it makes sense• Correcting errors with control set-point values• Calibration/repair of VAV boxes• Calibration of control system sensors• Correcting building pressurization control• Correcting the occupancy schedule• Correcting controls programming for correct operation
of Economizers• Repair/replacing inoperative steam traps
Sample of ECMs Implemented
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• Equipment Run-Time • Occupancy schedules & night setbacks to reduce fan/pump
run-time.
• Pressures• Reducing down-duct static pressure set-points to conserve on fan
energy consumption. Horsepower consumption is a ‘cubic’ relationship to cfm.
• A 10% reduction in airflow results in a 33% reduction in motor hp!
• Volumetric Flow Rates (Hydronic and Air) • Improper calibration of TU’s & incorrect airflow set-points for max.
& min. airflows have been found detrimentally impacting energy consumption on many boxes we have come across.
The Top Three…
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Winning the Gold Through Teamwork
What happens when the entire
team works together?
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www.mbpce.comjmascaro@mbpce.com
Armando J. de LeónUtilities EngineerVA State Corporation Commission
armando.deleon@scc.virginia.gov
James D. Mascaro, PE, CCPVice PresidentDirector of Commissioning Services
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