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13 CHAPTER FOUR ENERGY EFFICIENCY PRACTICES: MANAGEMENT AND OPERATIONS This chapter of the report will discuss practices for improving AUTOMATION AND CONTROLS energy efficiency at airports as they relate to energy manage- ment, including automation and controls, systematic assess- Computer controls, sensors, and whole-building automation ment, special programs and operational arrangements, and are used extensively by respondents to monitor and reduce personnel and human factors. energy consumption and provide data to support future energy efficiency projects. At an in-depth level the automation discussion will highlight ideas regarding upgrade and optimization of building auto- Building Automation Systems mation systems, techniques for calibrating and adjusting inte- rior temperatures, and specific controls retrofits supported by A building automation system (BAS) or Energy Management automation. Following automation, improvements to O&M Control System (EMCS), identified as a best practice by practices in relation to both new and retrofit projects will be numerous sources, "allow the building HVAC and lighting articulated into practices addressing methods of systematic systems to react automatically to the operating environment, assessment including audits, O&M assessment, and options for adjust to meet load conditions, and help schedule or identify commissioning. Topics related to special or unique programs equipment needing maintenance or adjustment" (Turner et al. and arrangements used by airports to guide, implement, and 2007, p. 10). Small airports often have some form of BAS pro- monitor energy efficiency projects will highlight project crite- viding minimum function such as "fire safety, security, and ria, temporary settings, and O&M service contracts. Finally, indoor air quality" (Turner et al. 2007, p. 3). human factors influencing energy efficiency will be discussed. These include targeted training programs for personnel and ten- BAS Thermal Environment Calibration $ ants, communications strategies for creating a "conservation culture," and psychological effects of certain retrofit practices. A variety of indoor thermal environments exist within airport terminals, ranging from gate-hold to baggage handling. Main- taining comfortable conditions for occupants with different Box 5 Practice Metrics Key metabolic rates and clothing levels who are departing to and Following the title of each practice in chapters four and five, arriving from different climates or continually entering and icons representing cost and payback are listed. Icon values exiting the building can be a challenge for BAS and airport are as follows: operators. Standards established by ASHRAE specify con- ditions of the indoor environment for occupant comfort. Low Cost = $ ASHRAE 55-2004 can be used for new construction and retro- Med Cost = $$ fit programs to establish parameters for proposed HVAC sys- High Cost = $$$ tems and to evaluate existing thermal environments. Although 02 year Payback = not prescriptively listing thermostatic settings for buildings, 25 year Payback = the standard provides guidance for determining acceptable 510 year Payback = conditions (Olesen and Brager 2004). 10+ year Payback = Example: $$ = this improvement has a Medium A majority of survey respondents that indicated energy Cost and 5- to 10-year payback. savings were attained by adjustment of space temperature settings described variously as "temperature adjustments Notes: and equipment shut down during non-peak hours"; "pro- For a limited number of practices, payback and cost infor- grammable thermostats"; "increase cooling temperature mation was not determined. ranges"; "space energy settings of 74 to 78 degrees sum- Practices with a payback of more than 10 years are beyond mer, 70 to 74 degrees winter" (noted by Phoenix Sky Har- the scope of this report and are mentioned for informa- bor International--PHX); and the utilization of "occupied/ tion purposes only. unoccupied temperature set locks." Where percentages are noted, the value given represents a yearly reduction in energy or operations costs for that sys- tem or process. Other sources noted that the best strategy for implementing temperature settings was to reset thermostats incrementally

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14 "one degree per week" to gradually transition spaces and occu- of energy savings, with many commenting that without auto- pants and reduce complaints by tenants (CAP 2004, p. 10). mation, energy efficiency improvements would not have been identified in the first place. These systems vary in size and Cost/Payback/Savings: In a heating condition "each degree scope of control and were identified by a number of names or of thermostat offset [higher] saves approximately 2% of cool- acronyms including "Intelligent Monitoring and Control Sys- ing energy [per year]" (Lynch and O'Rourke 2008, p. 26). tem" (IMACS)--"Open Architecture Building Automation" (OABA), as well as "automated building control system" (ABCS), "Direct Digital Control (DDC)," and "computer BAS Sensor Optimization $ - controlled terminal systems" or "automatic timed controls." An often-quoted concept relating to mathematics and com- For many facilities, including at those interviewed, automa- puter science termed "garbage in-garbage out" might be kept tion has become part of all building-related capital improve- in mind when managing building automation systems. With- ment projects and/or been an ongoing (yearly) retrofit for out accurate sensor calibration, BAS can return inaccurate distinct systems or terminal areas (concourses). A larger air- data, potentially wasting energy, disrupting occupant com- port noted that "automation of building systems is standard fort, and causing unnecessary wear or replacement of system in new facilities," whereas another noted an upgrade strategy components (Turner et al. 2007, p. 10). of "replacing building control system in multi-year phases" was improving efficiency. Optimization for HVAC and BAS can offset aging mechan- ical equipment and related sensors, and detect temporary As noted in other ACRP research, "an effective BAS repair or other emergency measures that have become "per- requires well-trained personnel, ongoing maintenance, cali- manent" fixes, ultimately saving energy resources (Turner bration, and well developed control schemes" (Turner et al. et al. 2007, p. 10). 2007, p. 12). Cost/Payback/Savings: Payback for optimization of BAS/ In addition to terminal improvements for automation, air- EMCS sensors has been documented at 1 to 4 years (Turner ports noted that other automation efforts have increased effi- et al. 2007, p. 14). ciency including "networking ancillary building HVAC sys- tems" and "extensive automation of district energy plant and Box 6 Open Source Automation distribution system." Currently being implemented at MSP, Open Architecture Cost/Payback/Savings: Owing to the scale of airports and Building Automation (OABA) is an extensive program that extensive variety in automation systems, costs for new sys- replaces building controls and facility monitoring systems tems can vary. Payback for upgrades to BAS/EMCS has been with new, nonproprietary systems, allowing the mainte- documented at 6 to 10 years (Turner et al. 2007, p. 14). If nance and operations staff to competitively bid work that nondigital/pneumatic systems are being replaced, additional was previously sole sourced by the respective vendors. While savings can be found in the decommissioning of those sys- implementing OABA, extensive testing was undertaken to tems (Turner et al. 2007, p. 14). improve equipment efficiency and update building controls, and system improvements have been included as hundreds BAS Improvements Related to Lighting See Lighting in chap- of pieces of equipment have been modified for the new ter five. system. When fully implemented this system is projected to deliver $150,000 in savings over the first 3 years by allow- BAS Improvements Related to Continuous Data Acquisition ing improved controls and maintenance of equipment. This See Continuous Commissioning in the Operations and Mainte- is one of the first open architecture building control systems nance section of this chapter. in the world. Box 7 Pneumatic Control Retrofit BAS Upgrade $$ Los Angeles International Airport (LAX) Tom Bradley Inter- BAS can reduce off-line time for crucial equipment by detect- national Terminal, a 25-year old, 1 million ft2 facility is under- ing fluctuations in performance or degrading components and going extensive renovations and expansion. These improve- alerting O&M staff earlier, potentially reducing unnecessary ments include the replacement of 19 roof-mounted air energy costs and more expensive repairs. Conversely, when handlers, variable-air-volume (VAV) distribution boxes, and poorly calibrated or incorrectly installed, BAS can increase an outdated pneumatic control system. New direct digital energy consumption (Turner et al. 2007, p. 10). controls coupled with other practices are predicted to reduce energy use by 10% annually. A number of respondents and interviewees noted imple- (Illia 2008; Seidenman and Spanovich 2008: Mawson 2009;) menting various levels of building automation as a key aspect