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The Business Case for Commissioning New and Existing Buildings Pacific Energy Center December 6, 2005 :1 The Business Case for Commissioning New and Existing Buildings Pacific Energy Center December 6, 2005 Evan Mills Lawrence Berkeley National Laboratory Collaborators: Mary Ann Piette & Norman Bourassa (LBNL) Hannah Friedman & Tudi Haasl (PECI) David Claridge & Tehesia Powell (Texas A&M) Sponsors: U.S. Department of Energy; CEC-PIER


Outline :2 Outline What is Commissioning? The Value Proposition Prospecting: Benchmarking to Identify Opportunities Cost-effectiveness Analysis Methods Break LBNL Study Best Practices Evaluation Tool


What is Commissioning? :What is Commissioning?


Commissioning is Quality Assurance :4 Commissioning is Quality Assurance A coordination process to optimize building performance (comfort, reliability, safety, energy) Articulating/verifying energy-related design intent Construction observation; warranty enforcement Controlling first cost Training operators Enhancing safety and risk management Creating more cohesion among team members


Commissioning is …. :5 Commissioning is …. … one of the most cost-effective means of improving energy efficiency in commercial buildings. … not an added cost. Rather it is a barometer of the cost of errors promulgated by others involved in design, construction, or operation. Commissioning agents are just the “messengers”. … common sense, but not common in practice.


Differences between Energy Auditing and Commissioning :6 Differences between Energy Auditing and Commissioning Begins earlier in building “lifecycle” More continuous (re-commissioning should be routine) Emphasizes no/low-cost improvements to existing systems Does not evaluate or recommend major capital retrofits Uses measurement and functional testing rather than simulation/stipulation of savings Builds capacity of in-house team (via training, better data logging, etc.) Strong emphasis on systems interactions and optimization More emphasis on non-energy benefits


History :7 History Born in ship-building industry: “Does the engine start?” versus “Will it float?” Originally applied in buildings in early 1980s to ensure performance of energy efficiency measures “Does a fan work?” versus “Should it be on?” It was later realized that “ordinary” buildings could achieve energy savings by correcting deficiencies


History (cont’d) :8 History (cont’d) 1989: ASHRAE developed HVAC commissioning guideline 1991: First utilities launched commissioning programs 1992: US Energy Policy Act required federal agencies to develop commissioning plans for their own buildings 1990s: ENERGY STAR Buildings and LEED (required) 1990s: R&D - e.g., DOE (federal) California PIER (state) 1998: PECI “National Strategy” 1998: Building Commissioning Association 2001: International Energy Agency “Annex 40” c.2003: California Commissioning Collaborative 2004: California Green Buildings Executive Order and Green Buildings Action Plan Many corporate initiatives, e.g. one of J&J’s “Top-10”


Is there a Need? :9 Is there a Need? All buildings are “Complex Prototypical Machines” (David Sellers) Many problems are masked by energy-wasting process (e.g., a stuck economizer is compensated for by over-running chiller) The process of designing, building, documenting, and operating buildings has become increasingly fragmented Design and operation often is done without regard to system interactions [moisture problems as evidence] Energy Efficient technologies tend to be more sophisticated (error prone?) than traditional techniques Hardware” does not equal “Hard Savings”


Is There a Need? (cont’d) :10 Is There a Need? (cont’d) Building problems (a.k.a. “deficiencies”) are pervasive These include Design flaws; Construction defects; Malfunctioning equipment; Deferred maintenance Don’t shoot the messenger: problems a combined result of fragmentation/specialization of trades, “value” engineering, increasingly complex building design and operation requirements, lack of clear design-intent documentation and performance targets, etc.


Problems Identified in THIS Building (the PG&E Energy Center) :11 Problems Identified in THIS Building (the PG&E Energy Center) Pumping head too high: Can result in excessive throttling or pumping Doglegs in ducting (unnecessary pressure drop) Oversized economizer damper Bad outdoor air temperature sensors (reported 99.9% RH on a sunny day) Ice storage pump starters set on manual (should be auto) Poorly located ice storage temperature sensors


Case Study: Kleberg Building :12 Case Study: Kleberg Building INITIAL CONDITION - upper [red] clouds • Continuous preheat - 105F (intentional) PHASE 1 MEASURES - middle [blue] • Preheat off PHASE 2 MEASURES - lower [blue] • Preheat to 40F • Optimize cold deck temps • Reactivate economizer mode • Static pressure optimization • Night-time setback • Replaced or repaired VFD boxes • Restarted chilled water VFD • CHW pump control staging • Building stack pressure reduced • Fume hood exhaust pressure reduced IMPACTS • Chilled water: 64% reduction • Hot water: 84% reduction • $314,000 annual energy cost savings


Broken Dampers :13 Broken Dampers


Fouled Filters :14 Fouled Filters Condensation damage from DX fan coil unit due to plugged filter and low air flow. Large high school.


Faulty Controls :15 Faulty Controls Hunting of hot deck temperatures with pneumatic control due to sensor thermal mass, steam valve sizing, and controller proportional band. Older high-rise office building. Hot deck Tempered deck Temperature


Poor Coordination Among Trades :16 Poor Coordination Among Trades Inadequate cooling and excessive fan power consumption due to poor fit between light troffer diffusers and duct boot provided by a different supplier, allowing up to 25% of flow at diffuser to bypass directly into ceiling plenum. Highrise office tower.


Envelope: air leakage and moisture management :17 Envelope: air leakage and moisture management Damage to brick facade of pool building due to lack of specification for (a) sealing of air leakage paths in exterior envelope and (b) balancing to assure negative pressurization of pool area. Large newer middle school.


Design-operation Mismatch :18 Design-operation Mismatch Outside air flows as a percent of required air flow for current occupancy and ventilation standards. Twelve rooftop units at an elementary school.


Energy Consequences :19 Energy Consequences


The Value Proposition :The Value Proposition


Value Proposition - Perspectives :21 Value Proposition - Perspectives For Building Owners/Occupants Comfort/productivity; continuous occupancy Warranty enforcement Reduced construction time Occupant/tenant satisfaction Enhanced equipment life Reduced maintenance costs For Trades Improved information flow among team members Reduced call-backs or change orders Increased likelihood of client satisfaction For Utilities/”Policy People” Program success: e.g. customer acceptance Meeting and maintaining targeted savings


Value Proposition - Sources of Value :22 Value Proposition - Sources of Value Energy Savings Improved efficacy of EEMs Even “Ordinary Buildings” can get savings Securing the achievement of O&M goals Non Energy Benefits Risk Management


Value Proposition - Sources of Value :23 Value Proposition - Sources of Value Not attending to problems can cause: Discomfort --> Eroded productivity, absenteeism Indoor air quality problems Premature equipment failure Litigation Excessive energy and construction costs


Energy & Non-Energy Impacts :24 Energy & Non-Energy Impacts


Prospecting:Benchmarking to Identify Opportunities :Prospecting:Benchmarking to Identify Opportunities


Benchmarking - High-Tech Facilities :26 Benchmarking - High-Tech Facilities Energy intensity varies by orders of magnitude - suggesting opportunities


Benchmarking - Cleanrooms (1 of 2) :27 Benchmarking - Cleanrooms (1 of 2) Recirculation air costs vary by factor of 8 in similar cleanrooms


Benchmarking - Cleanrooms (2 of 2) :28 Benchmarking - Cleanrooms (2 of 2) ACH varies by factor of 6 for similar cleanrooms


Benchmarking - Laboratories :29 Benchmarking - Laboratories Energy cost intensity varies by factor of 8


Benchmarking - Data Centers :30 Benchmarking - Data Centers HVAC “effectiveness” (HVAC energy/total energy)varies by 2.5x [low value is better]


Benchmarking - Datacenters :31 Benchmarking - Datacenters Power density varies by 20x, and lower than rules-of-thumb in every case!


Cost-Effectiveness Analysis :Cost-Effectiveness Analysis


Cost-Benefit Formula :33 Cost-Benefit Formula Simple Payback Time (years) = Commissioning cost +/- Non-energy impactsAnnual Energy Savings +/- Non-energy benefits Advantages of PBT: intuitive; familiar; does not rely on discounting; does not require stipulated measure life


Ways of Thinking about Costs and Savings :34 Ways of Thinking about Costs and Savings Source: Northeast Energy Efficiency Alliance Saving energy is rarely the number-one driver or reason for embarking on a commissioning project, although energy systems often at the root of problems


Factors Effecting Project Cost :35 Factors Effecting Project Cost Scope & thoroughness Available documentation Number of systems (sampling vs 100% inspection) System complexity Number of zones Existing metering/gauges, utility history, EMS trends Measurement equipment costs (purchase/rental) Commissioning agent involvement On-site staff involvement Reporting Cleverness


Factors Effecting Project Savings :36 Factors Effecting Project Savings Savings persistence is uncertain (intrinsic to the kinds of issues requiring commissioning) Recommendations often only partly implemented at the time that evaluation often occurs Not all recommendations will necessarily be implemented Savings cannot be directly measured in new construction (lack of “baseline”)


Examples of Non Energy Impacts :37 Examples of Non Energy Impacts Altweis (2002): six projects in which change orders were reduced by 87%; contractor call backs by 90%; construction cost reduced 4-9%. Tso et al (2002): an average of 12 measures per project (new construction) and 9 measures (existing buildings) resulted in extended equipment life Sellers: Cleanroom filtration: One change-out fills a warehouse with media (disposal cost). Pre-Cx: changes made by calendar, not by need. Shift to extended-surface; pressure drop cut in half and filters lasted 2x as long. Better filters had no metal frames (cut recycling costs) [courtesy David Sellars] Sellers: 34 air handling units cycling 87,600 cycles per year (more than actuator design life; actuator replacement cost $300-$500) Replacements avoided at cost of $150-$200 in labor to diagnose and correct problem. Nelson (1999): twelve legal claims (aggregate award of $60 million) could have been avoided by proper commissioning.


Includable Cost Items :38 Includable Cost Items Cx provider's fixed costs Contractor Cost: Coordination with commissioning provider Improving design or operations Functional tests Resolution costs related to optimizing systems Costs related to ensuring other trades' contract adherence Resolution costs related to operations and maintenance Minor capital improvements to resolve deficiencies Training of on-site staff Utility rebates, grants, or other external financial incentives Travel Non-energy impacts


Excludable Cost Items :39 Excludable Cost Items "Non-billable" in-house operations staff fixed costs Contractor Cost: Contract compliance Testing and balancing (TAB) Correcting design flaws Resolution costs related to installing a system beyond project scope Major capital improvements to resolve deficiencies Research-related costs


15-minute break :15-minute break


LBNL Study :LBNL Study


LBNL Study of Cx Projects in 224 Buildings :42 LBNL Study of Cx Projects in 224 Buildings Meta-Analysis (some primary information) Focus on energy aspects, but also non-energy impacts Separate treatment of existing and newly constructed buildings Standardized analysis (definitions, normalized energy prices, inflation) Extensive statistical and correlation analyses


Methodology :43 Methodology Developed metrics to characterize performance Developed standardized language for describing Cx scope Developed standardized framework for characterizing deficiencies and measures (“Measures Matrix”) Collected data from the literature and Cx providers Reviewed data quality Performed normalizations Standardized energy prices Construction costs corrected for inflation ($2003) Commissioning costs corrected for inflation ($2003) Analysis and inter-comparisons Analyze subgroups (new/existing; building type) Identified correlations (or lack thereof) Identified data gaps


Resulting Sample Characteristics :44 Resulting Sample Characteristics 224 buildings (175 projects), of which 150 are existing buildings and 74 are new construction 18+ commissioning providers Largest sample yet compiled Diversity of building types 30.4 million square feet across 21 U.S. states Existing buildings: median 151,000 ft2 New construction: median 69,500 ft2 $17 million investment ~7000 problems identified Projects span two decades, but most done in the 1990s


Location of Projects :45 Location of Projects


Types of Buildings :46 Types of Buildings


Top-level Findings :47 Top-level Findings Existing Buildings Cx cost: $0.27/ft2 • Median NEBs: $0.18/ft2 Deficiencies: 11 per building Energy Savings: 15% Payback time: 8.5 months New Construction Cx cost: $1.00/ft2 • Median NEBs: $1.24/ft2 Deficiencies: 28 per building Payback time: 4.8 years Cost-effective over range of energy intensities, building types, sizes, locations Most successful: energy-intensive buildings Cost-effective outcomes harder in small buildings Energy savings rise with more thorough commissioning


Commissioning Scope: Existing Buildings :48 Commissioning Scope: Existing Buildings Develop or update design intent documentation Plan Utility analysis, benchmarking Trend analysis Building modeling Findings Estimate benefits from interventions Update system documentation (e.g. control sequences) O&M improvements Capital improvements (grey zone) Monitor fixes Measure impacts Systems manual/recommissioning manual Report


Slide 49:49 Scope


Savings Scale with Commissioning Scope(Existing Buildings) :50 Savings Scale with Commissioning Scope(Existing Buildings)


Commissioning Scope: New Construction :51 Commissioning Scope: New Construction Develop design intent documents Specifications Plan Design review Sequences of operation (if not already available) Review submittals Construction observation Verification checks Functional testing Issue resolution Training Review O&M manuals Systems manual/recommissioning manual Trend analysis; evaluate energy savings Report


Slide 52:52 Scope


Reasons for Commisisoning: Existing Buildings :53 Reasons for Commisisoning: Existing Buildings


Reasons for Commissioning: New Construction :54 Reasons for Commissioning: New Construction


Types of Deficiencies Discovered :55 Types of Deficiencies Discovered Existing (N=3500) New (N=3300)


Measures Matrix :56 Measures Matrix


Cost Allocation :57 Cost Allocation Existing Buildings (N=55) New Construction (N=5)


Normalized Costs :58 Normalized Costs


Outliers :59 Outliers Smaller bldgs tend to have higher Cx costs Larger bldgs tend to achieve economies of scale


Observed Non-Energy Impacts :60 Observed Non-Energy Impacts Existing Buildings (N=55) New Construction (N=5)


Non-Energy Benefits Often Offset Cost of Commissioning :61 Non-Energy Benefits Often Offset Cost of Commissioning 20 projects


New Construction: Costs range from -1% to 2%+ of total construction cost :62 New Construction: Costs range from -1% to 2%+ of total construction cost Inclusion of non-energy benefits (e.g. equipment downsizing, reduced callbacks, … significantly reduces costs


New Construction: Costs range from -1% to 2%+ of total construction cost :63 New Construction: Costs range from -1% to 2%+ of total construction cost Inclusion of non-energy benefits (e.g. equipment downsizing, reduced callbacks, … significantly reduces costs Laboratory;extensive Cx;NEBs


Up to 50% Whole-Building Energy Savings :64 Up to 50% Whole-Building Energy Savings High savings even for non-energy-intensive buildings Median: 15% Average: 18% Many are HW/CW/Steam campus systems


Energy Savings & Payback Times Independent of Pre-Cx Energy Intensities :65 Energy Savings & Payback Times Independent of Pre-Cx Energy Intensities


Payback Times: Existing Buildings :66 Payback Times: Existing Buildings Attractive payback times across a range of Cx costs Median Payback Time = 0.7 years Excluding NEI’s $/year


Payback Times: New Construction :67 Payback Times: New Construction Payback times not always attractive (if NEBs excluded) Median Payback Time = 4.8 years $/year


Payback Time Distribution by Measure :68 Payback Time Distribution by Measure N=200 measures


Payback Time Distribution by Measure :69 Payback Time Distribution by Measure Typically capital-intensive measures, e.g. install vacuum pump, replace VSD, … N=200 measures


Results vary by building type: Existing Bldgs. :70 Results vary by building type: Existing Bldgs. Key: diameter proportional to % energy savings


Results vary by building type: New const. :71 Results vary by building type: New const.


Emergence & Persistence of Energy Savings :72 Emergence & Persistence of Energy Savings


Existing Buildings vs. New Construction :73 Existing Buildings vs. New Construction Existing buildings larger greater normalized energy savings more cost-effective (excluding NEBs) New construction less comprehensive normalized costs higher larger non-energy benefits NEBs are a more important motivation for embarking on commissioning, and can go farther in offsetting the cost of commissioning more deficiencies found


National Potential; National Need :74 National Potential; National Need $18 billion annual energy savings potential (US-wide) -- plus non-energy benefits Without commissioning, many energy-efficiency projects, programs, and policies will often fall short of their goals


Best Practices :Best Practices


Best Practices for Value Maximization :76 Best Practices for Value Maximization Be thorough in the Cx process (savings likely to be higher) Catch problems at time of design (pre-construction) Fix problems as you go (to the extent possible) Do not get “dinged” for O&M, TAB, hardware upgrades, warranty-related work,… Emphasize NEBS (valued and unvalued – value not necessarily expressed in $) Meter for a reason; don’t skimp, but don’t pay for excessive accuracy. Temporary versus permanent loggers/meters Persistence enablers: design review, benchmarking, trending, system diagnostics, document sequences of operations, training Sampling (e.g. check 1 in 10 fan boxes) Quick tests: shut down bldg; wait one hour and restart (or come in AM) – you’ve step-changed almost every process [test for power recovery] Obtain and review complaint logs Limited budget: design review, design for lowest-cost O&M and future RCx, functionally test critical items, trend analysis


Recommendations :77 Recommendations No energy management program is complete without commissioning (in-house or outsourced) Invest in commissioning (existing buildings and new construction) Institutionalize the process Benchmark, track outcomes, ensure persistence, refine process


Evaluation Tool :Evaluation Tool


Cx Project Evaluation Tool :79 Cx Project Evaluation Tool A simple spreadsheet tool for cataloging, comparing, and evaluating commissioning project information Pre/post energy use, costs, savings, payback times Project characteristics Non-energy impacts Download: http://eetd.lbl.gov/emills/PUBS/Cx-Costs-Benefits.html


Cx Project Evaluation Tool :80 Cx Project Evaluation Tool TABS Instructions Main Data Sheet Measures Measures Key Building Type Key M&V Key Cost Rules Non-Energy Impacts


Cx Project Evaluation Tool :81 Cx Project Evaluation Tool


Cx Project Evaluation Tool :82 Cx Project Evaluation Tool


Cx Project Evaluation Tool :83 Cx Project Evaluation Tool


Cx Project Evaluation Tool :84 Cx Project Evaluation Tool


Cx Project Evaluation Tool :85 Cx Project Evaluation Tool


Cx Project Evaluation Tool :86 Cx Project Evaluation Tool


Resources :87 Resources PECIhttp://www.peci.org CA Commissioning Collaborative online libraryhttp://resources.cacx.org/library/ LBNL cost-benefit study(and spreadsheet download) http://eetd.lbl.gov/emills/PUBS/Cx-Costs-Benefits.html Commissioning Functional Test Guidehttp://buildings.lbl.gov/hpcbs/FTG Design Intent Toolhttp://ateam.lbl.gov/DesignIntent/home.html Energy Design Resourceshttp://energydesignresources.com Pacific Energy Center Cx workshops!


Participate in our ResearchContribute Data :Participate in our ResearchContribute Data Evan Mills Lawrence Berkeley National Laboratory 510-486-6784 • emills@lbl.gov http://eetd.lbl.gov/emills/PUBS/Cx-Costs-Benefits.html