
9c621d2609c4dee06c358c272e67790b.ppt
- Количество слайдов: 22
Retrocommissioning Presented to: Airports Council International May 4, 2008 Denver, Colorado 1
Introduction to Retrocommissioning • • • Retrocommissioning (RCx) is a systematic process that focuses on the operation of systems and controls in existing buildings that were not originally commissioned; intended to optimize how equipment operates as an integrated system Also applicable to systems not necessarily associated with buildings; for example, source de-icing glycol collection Generally concentrates on mechanical, controls, and lighting systems (energy-using equipment) Maximum opportunities for energy savings in complex buildings Uses low-cost improvements rather than expensive capitalintensive retrofit measures Highest return on capital investment opportunities for any airport property 2
The Retrocommissioning Process Planning Phase • Select project • Set project objectives and obtain support • Select RCx lead • Document current operating requirements • Perform initial site walk-through • Develop RCx plan • Assemble RCx team • Hold project kick-off meeting 3
The Retrocommissioning Process Investigation Phase • Review facility documentation • Perform diagnostic monitoring • Perform functional testing • Perform simple repairs • Develop master list of findings • Prioritize and select operational improvements Implementation Phase • Develop implementation plan • Implement selected operational improvements • Verify and document results 4
The Retrocommissioning Process Hand-Off Phase • Develop final report • Compile systems manual • Develop re-commissioning plan • Provide O&M training • Conduct close-out meeting • Implement persistence strategies 5
Cost of Retrocommissioning Cost Allocation (Existing Buildings, N=55) Verification & Persistence Tracking 2% Reporting 2% Implementation 27% 5. 2 Million ($2003) for whole Sample Investigation and Planning 69% 6
RCx Market Structure Demand-Side Market • Building Owners: owner-occupants and investor-owners, public and private sector entities, owner’s representatives, property management companies, facility or property managers, and other financial decision-makers • Most concerned with life safety issues, operating costs and/or occupant comfort Supply-Side Market • Engineering firms, design professionals, general contractors, HVAC/controls contractors, commissioning specialists, TAB contractors, energy services firms, and O&M service contractors. • May involve in-house staff of Building Owners • Building Commissioning Association (BCA) established professional standards 7
Reasons for Retrocommissioning • • • Life safety issues discovered following initial construction and turnover Problems never identified during initial building start-up, such as improper sequences of operation Systematic problems in building operation, such as simultaneous heating and cooling Environmental problems Excessive equipment run times due to changes in occupancy or space use, such as unnecessary lighting Malfunctioning equipment or sensors, such as broken dampers Control optimization issues, such as sub-optimal chilled water supply temps Excessive equipment repair and replacement costs High utility bills Indoor air quality concerns High employee absenteeism Frequent tenant turnover 8
Reasons for Retrocommissioning Number of Deficiencies Identified by Building System (Existing Buildings, N = 3, 500) Other 16% HVAC (combined heating and cooling) Cooling plant 2% 6% Heating plant 3% Air handling & distribution 20% Unknown 47% Facility-wide (e. g. EMCS or utility related) 2% 11 Deficiencies/Building Terminal units 2% Lighting 2% Plug loads 0. 1% Envelope 0. 1% 9
Airport Commissioning and Retrocommissioning • • Operation and development of commercial airports are acutely impacted by air and water quality standards Environmental impact of run-off to adjacent properties Both direct and indirect air emissions created by airport capital improvement projects must be included in a State Implementation Plan for air quality Noise no longer dominant airport environmental issue. 10
Barriers to Retrocommissioning • • • Lack of awareness of benefits of RCx Difficulty identifying qualified providers Perception that RCx is expensive with long-term paybacks Lack of confidence in the anticipated results Misunderstanding of the types of building and system performance problems that RCx can address Split incentives between owners and tenants in lease spaces Internal accounting practices in owner-occupied spaces that do not return RCx savings to those who fund the services Lack of time, short-planning horizons, and institutional inertia No established budget, procurement vehicle, internal responsibility, management system, or precedent for procuring RCx services 11
Financial Benefits of RCx • • • RCx can produce savings of 5 -20% of total building energy costs, with simple payback averaging less than 2 years A study of 100 buildings in 2004 found median energy savings of approximately $45, 000 per building and ranged as high as $1. 8 million Natural Capitalism: “It may be that managers can’t afford not to retrofit buildings to save energy, because doing so can make workers more productive. If labor productivity goes up just one percent, that will produce the same bottom-line benefit as eliminating the entire energy bill. ” 12
Building Energy Savings ($2003) Financial Benefits of RCx Median Payback = 0. 7 years 13
Non-Financial Benefits of RCx • • • Identify and correct life safety issues Extended equipment life Improved indoor air quality Reduced O&M costs Upgrade system operation reliability Improved comfort and worker productivity More knowledgeable building staff Increased net operating income and tenant retention Expose staff to different approaches for troubleshooting problems and improved staff understanding of equipment and control strategies Early detection of equipment issues 14
Case Study 1: Dallas/Fort Worth International Airport Retro-Commissioning And Facility Condition Assessment Program: Existing Terminals • Facilities approximately 35 years old • Terminals leased to airlines, which had responsibility for operations and maintenance, now reverting to DFW • Recognition of energy and occupant comfort issues • Reliability of HVAC and electrical system operation are critical • Designation as Serious Non-Containment Area imposes significant limits on emissions for central plant operation. Systems Not Associated With Buildings • Systems that involve process are prime candidates for RCx • Environmental issues can become “trigger” to initiate RCx. Program Status • Initial activities underway; benchmarking will provide basis to evaluate success • Seed funding will be supplemented by cost savings • Key element of long term asset management strategy. 15
Case Study 2: Hawaii Airports Honolulu International Airport, Terminal Modernization, New Mauka Concourse Improvement • Estimated 30% energy savings ($300, 000) Renovation of Airport Lounge, Honolulu International Airport • Estimated 15% energy savings ($562. 50) Kona International Airport, Terminal Modifications • Estimated 30% energy savings ($440, 000) Molokai Airport Aircraft Rescue Fire Fighters Station Improvements • Estimated 20% energy savings ($31, 200) 16
Case Study 2: Hawaii Airports (New Commissioning) • • Hawaii Department of Transportation Airports Division (DOTAirports) is considering a similar cold ocean-water air conditioning system for the enclosed areas of Kona International Airport DOT-Airports has made efficiency improvements in taxiway lights and airfield lighted signs at the Honolulu, Hilo, and Kalaeloa airports, and replaced the chiller plant at Kahului airport with more efficient equipment 17
Case Study 2: Peterson Air Force Base Retrocommissioning Background: • 30, 000 square foot facility in Colorado Springs, CO. • Airlift Flight Control Facility with direct access to base’s main runway • Houses offices, meeting space, classrooms, parachute repair area, storage, kitchen, airlift loading bay, and electrical and mechanical rooms Issues Discovered: • Hot water heating boiler often tripped into alarm mode. • Temperature of three classrooms on first floor determined to be consistently lower than their operational set point • Air handler heating valve was 100% open for a large portion of the day when the outside temperature was 65 degrees 18
Case Study 2: Peterson Air Force Base Retrocommissioning Recommendations: Heating Hot Water Heating System • Set boiler enable to off when outside air temperature greater than 60°F. This would keep the boiler from cycling and eliminate unnecessary usage of the boiler. • Test and rebalance hydronic heating hot water system. This would improve the efficiency and performance of the heating hot water system. Chilled Water System • Chilled water temperature should run on a linear reset parameter based on outside air temperature similar to heating hot water boiler. This would eliminate overcooling of spaces and eliminate need for unnecessary VAV terminal reheat. Air Distribution System • Test and rebalance air distribution system throughout building. This would reduce energy consumption by improving performance of the air handler and associated VAV boxes. Would also reduce excess noise at the diffusers. • Revise the operational schedule of the air handler AHU-1 within the building automation system to accurately depict the occupancy within the facility. 19
Questions? George Bourassa, PE, LEED AP, CCP Jacobs Carter Burgess george. f. bourassa@jacobs. com 312. 466. 5723 20
Sources • • 2007. White Paper: Retrocommissioning Your Building for Savings. Retrocommissioning Services & Incentives Program. http: //www. rcxprogram. com/docs/PG&E%20 RCx%20 White%20 Paper. pdf Dodds, Debby, Eric Baxter, and Steven Nadel. 2000. Retrocommissioning Programs: Current Efforts and Next Steps. Proceedings of ACEEE Summer Study on Energy Efficiency in Buildings 4: 479 -93. Washington, DC: American Council for an Energy. Efficient Economy. http: //resources. cacx. org/library/holdings/020. pdf Haasl, Tudi et al. Retrocommissioning’s Greatest Hits. Portland Energy Conservation, Inc. , http: //www. peci. org/Library/PECI_RCx. Hits 1_1002. pdf Mills, Evan et al. 2004. The Cost Effectiveness of Commercial Buildings Commissioning: A Meta-Analysis of Energy and Non-Energy Impacts in Existing Buildings and New Construction in the United States. Lawrence Berkeley National Laboratory, PECI, and Energy Systems Laboratory, Texas A&M University. http: //eetd. lbl. gov/emills/PUBS/Cx-Costs-Benefits. html State of Hawaii Department of Business, Economic Development & Tourism. 2008. Lead by Example: State of Hawaii Agencies’ Energy Initiatives FY 2006 -2007. Report to the 2008 Hawaii State Legislature. http: //hawaii. gov/dbedt/info/energy/publications/LBE-all-07. pdf Thorne, Jennifer and Steven Nadel. 2003. Retrocommissioning: Program Strategies to Capture Energy Savings in Existing Buildings. American Council for an Energy. Efficient Economy. http: //www. aceee. org/pubs/a 035 full. pdf Hawken, Lovins and Lovins. 1999. Natural Capitalism 21
Case Study 2: Peterson Air Force Base Retrocommissioning Recommendations: Domestic Hot Water Heating System • Place domestic hot water heater on time clock that follows parameters of building occupancy schedule. This would reduce energy consumption by turning off domestic hot water heater during unoccupied times of the day. Lighting Control • Place all interior lighting on time clock(s) or the building automation system. This would reduce energy consumption by turning off interior lighting during unoccupied times of the day. • Install wall switch sensors in smaller rooms such as the kitchen, storage and offices. Install combination sensors in toilet room. Install ceiling sensors in corridors and large rooms. This will greatly reduce energy consumption and reduce maintenance from replacement of lamps. System Monitoring • Long-term data logs should be created for adequate trending for monitoring each system. Once the trends are available, a user would be able quickly diagnose the facility for any problems prior to failures. This also will show any sudden changes in energy consumption. 22