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15 Motor Controls In conjunction with building automation and systems mon- itoring, electric motors within many existing air-handling, pumping, and conveyance equipment can be outfitted with computer controls or variable frequency drives (VFDs) that sense real-time load or demand and automatically adjust to optimal efficiency (Turner et al. 2007, p. 13). These controls provide more precise feedback to operations staff, allowing adjustment and fine-tuning of settings to accommodate airport schedules and occupancy. Multiple respondents indicated uti- lization of motor controls on a variety of equipment. Smaller airports used VFD fans, whereas larger airports also used VFD pumps and cooling tower fans. Fans--Variable Speed Drives $ - Application or replacement of VFD controls to fans through a BAS was identified as an energy saving action by a majority of airports surveyed. Respondents indicated payback dura- tions of between 0 and 5 years and low cost, which correlates with other findings by Turner of 3 to 7 years for simple pay- back (Turner et al. 2007, p. 14). Pumps--Variable Speed Drives $ - $$ FIGURE 3 Motor controls. Variable frequency drives for Motor controls for pumps were used by various sized airports condenser water pumps save energy at MSP Airport. (Courtesy: Michaud Cooley, Erickson Engineers.) and were noted to have a payback time of 2 to 5 years and low to medium cost (see Figure 3). sure considered" (Turner et al. 2007, p. 10). Reasons given for this assertion consider the low cost of O&M measures, ability Fans--Cooling Tower $ - $$ of in-house staff to implement improvements, and immediate payback of O&M actions (Turner et al. 2007, p. 10). In addi- Retrofit of cooling tower fans with variable drive was identi- tion, these improvements "rarely require the design time, bid fied by larger airports as an energy efficiency strategy with paybacks ranging from 2 to 5 years and low to medium cost. preparation, evaluation, and response compared to capital pro- jects that can take up to a year to implement" (Sullivan et al. 2004, p. 2.3). OPERATIONS AND MAINTENANCE This report generally agrees with this assertion, but cau- Respondent airports and literature sources noted that evalua- tions that for many small airports, limited staff resources and tion of on-going engineering programs and system evaluations outside facility management contracts may increase imple- such as energy audits and commissioning can significantly mentation cost and payback time. improve energy efficiency in airport terminals. Earlier studies noted that all airports should prioritize the "development a Respondents suggest that small airports identify a party to comprehensive energy-related O&M program with clearly manage the implementation of specific energy-related O&M defined goals and benefits" as a way of improving energy effi- practices. This position at a small airport may be best per- ciency (Turner et al. 2007, p. 10). Further, it was stated that it formed by a specialist with previous experience in perform- was important that these programs "set aggressive goals and ing commissioning at the facility. secure funding and senior management support [and main- tain] implement and monitor benchmarked results" (Turner et al. 2007, p. 10). Systematic Evaluation It is the opinion of some experts that "while effective . . . Influenced by "record high energy prices, an increased num- capital upgrades [like equipment replacement] are not always ber of building re-commissioning agents, and the increased the most cost-effective solution" and "that low-cost/no-cost awareness of airport executives and the public of the direct O&M measures . . . should be the first energy savings mea- link between energy and the environment," evaluation and

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16 maintenance of existing systems will continue to be an acces- Energy Assessment $$ - sible, effective, and valuable method of improving energy efficiency (Turner et al. 2007, p. 5). Energy assessments offer a combined evaluation of equipment and operations and are often performed by external experts. More than half of the survey respondents have initiated As such, these reports that identify "potentially beneficial energy audits, assessments, or other intensive energy studies. equipment upgrades, needed equipment repairs, and benefi- Building commissioning, periodic re-commissioning, or cial changes in operating procedures" can represent the most on-going commissioning for existing facilities through build- objective opinion of what is needed to reduce costs and there- ing automation was noted as providing additional savings fore be very useful in support of energy efficiency programs in energy costs by a number of respondents. Phoenix Sky (Turner et al. 2007, p. 11). Turner indicated that comprehen- Harbor International Airport noted that its first commis- sive assessments be undertaken every five years. sioning attempt was recently undertaken. Re-Commissioning and Optimization $ Energy Audits $ Re-commissioning and optimization for existing buildings or systems will return those systems to design specifications while Energy audits can take on various forms and scopes, but all accommodating facility or tenant operating requirements. types focus on evaluation of the energy used by existing equip- These actions can apply to single systems in a "Value Re- ment over a period of time. Traditional audits result in techno- Commissioning" approach or include comprehensive building logical solutions to save energy. Energy bills are often reviewed evaluation to support extensive retrofit/remodeling (Sullivan for inconsistency with monitoring equipment and errors as et al. 2004, p. 7.2). Because of its temporal nature, re- well as trends in an effort to identify efficiency opportunities. commissioning is most effective for buildings or tenant spaces lacking consistent maintenance. A change in tenant or use As part of an equipment replacement process (investment within a space offers an opportunity to re-commission sys- grade) energy audits are often a financing requirement that tems serving that space. serves to provide assurance that the "investment is financially sound" (PECI 1999b, pp. 45). Specific optimization actions cited by respondents included "chiller controller reprogramming through a BCS/EMS Cost/Payback/Savings: Energy audits are often performed [energy management system] system"; "monitoring of chiller for free by the local utility. plants to avoid peak demand charges"; and shut down of hot water boilers in the summer months." Other optimiza- WEBLINK--Energy Efficiency Handbooks tion actions noted by Sullivan et al. include: These handbooks by the California Energy Commission include comparisons of different types of energy audits and Adjust reset and set-back temperatures and temperature settings--Settings are often adjusted over time based on per- information on identifying energy efficiency projects. sonal preferences, to compensate for inadequate system opera- http://www.energy.ca.gov/reports/efficiency_handbooks/ tion, or to achieve energy savings. In addition, sensors require periodic recalibration. Staging/sequencing of boilers, chillers, and air handling units-- Equipment should be operated in the most efficient combina- O&M Assessment $ - $$ - tion of chillers, boilers, and fans at varying load conditions. Adjust and repair dampers and economizers--Malfunctioning An O&M assessment seeks to reduce operating costs and or poorly tuned dampers (including seals, actuators, and link- improve efficiency by recommending "low-cost changes in ages) and economizers result in (1) increased supply air fan energy in the closed position or require additional air heating O&M practices that can improve building operation" (PECI and cooling when open too much, (2) undesired building oper- 1999b, pp. 45). They can be performed before or concurrent ating conditions owing to lack of outside air, and (3) prema- with energy audits and may aid in reducing the payback time ture equipment degradation and replacement. for capital improvements identified in the energy audit because Modify control strategies for standard hours of operation-- Motors, pumps, fans, and air handlers often operate on a 24/7 of low-cost operations improvements (PECI 1999b, pp. 45). schedule even though not required by either the building tenants By utilizing assessment in preparation for an audit, their com- or the building operating plan. plementary nature may be exploited to identify additional or Eliminate simultaneous heating and cooling--Heating and cooling systems for the same space can compete against each more precise areas of investigation in the audit. other owing to improper setpoints. Air and water distribution balancing and adjustments-- Cost/Payback/Savings: Costs for O&M assessments are Systems require rebalancing due to drift and changing building/ workspace mission and/or tenant requirements. typically equivalent or sometimes more than energy audits; Verify controls and control sequencing including enabling and however, implementation costs are small relative to large cap- re-enabling automatic controls for setpoints, weekends, and hol- ital improvements (PECI 1999b, pp. 45). PECI reports that idays. Verify that overrides are released (Sullivan et al. 2004). "managers can consider most O&M assessments outside of typical corporate hurdle rates, because the risk of not realizing These optimization strategies can often return both energy effi- savings is so low" (PECI 1999b, pp. 45). ciency savings and O&M improvements if they are performed

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17 by staff and will raise awareness of energy savings potential. However, consultation with a skilled agent may be necessary for complex improvements. By targeting specific systems or components of a system through value re-commissioning data "can be used to demonstrate benefits of larger, more aggres- sive existing building commissioning program" (Sullivan et al. 2004, p. 7.2). Cost/Payback/Savings: Optimization efforts typically have a payback of less than two years (Sullivan et al. 2004). Other benefits of optimization for mechanical systems can include longer equipment life and a reduced chance of equipment failure. Box 8 Programmatic Assessment Programmatic assessments are especially useful when plan- FIGURE 4 Data gathering for commissioning. A variety of tools ning for renovation or retrofit. Evaluate occupancy patterns and sensors are used to measure airflow speed and pressure, and space uses to determine if original design and mechanical/ component and air temperature, electrical power and voltage. lighting specifications are still in place or if changes to space From Top Left--Counter Clockwise: Fluke 87 Multimeter: Used for general measurement of electrical voltage, current, and mean changes to system settings. frequency. Dranetz PowerXplorer: Used to measure and data "Have occupancy patterns or space layouts changed? Are log very small fluctuations of electrical voltage, current, and frequency. Primarily used when testing data center electrical HVAC and lighting still zoned to efficiently serve the spaces?" systems. Shortridge Instruments-AIRDATA Multimeter-- ADM-860: Used to measure airflow, velocity, pressure, and (PECI 1999c, p. 4) temperature. Vaisala Temperature/Humidity Meter: Used to measure data log temperature and humidity. (Center) Raytek Infrared temperature Gun: Used to measure surface temperatures. (Image and descriptions courtesy Michaud Basic Commissioning $ - $$$ - Cooley Erickson Engineers.) Basic commissioning, as a part of O&M best practices, is cited multiple times in the literature (Liu 2002; Sullivan et al. 2004; Lighting sweeps or day-lighting controls Commonwealth of Pennsylvania n.d.) as a primary method for Energy management systems and control strategies improving performance and efficiency of building systems. Variable speed drives in motors Ventilation air and control Basic commissioning for a new or retrofit system or build- Building pressurization control ing ensures that equipment is installed and operating prop- Refrigeration improvements erly. When taking possession of a building or system that Capacity controls for heating and cooling plant equip- has undergone commissioning, owners gain assurance that ment (PECI 1998, p. 55). equipment is operating within design parameters and specifi- cations (Sullivan et al. 2004, p. 7.2). In addition, the training implemented for staff as well as data and documentation col- Cost/Payback/Savings: Costs and payback time will vary lected will ensure optimal operations and support future re- owing to scale and scope of the commissioning of project. commissioning (see Figure 4). WEBLINK--Commissioning Resources It is suggested that commissioning be initiated early in the Portland Energy Conservation, Inc. provides an design process to achieve the greatest benefit (Potter et al. in depth list of on-line commissioning resources: 2002). http://www.peci.org/cx_resources.html Specific projects that warrant commissioning as identified by the PECI include: Continuous CommissioningTM $$$ - All projects that include controls Continuous CommissioningTM describes a commissioning Pneumatic equipment practice that is integrated into the day-to-day O&M program Integrated systems at a facility. Data compilation, calibration, and other activi- HVAC-related plant equipment and air distribution ties are performed on a regular (often daily) basis. This con- systems trasts to other commissioning events, which are distinct and

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18 temporal in nature. The approach was developed by the Special Programs and Operational Arrangements Energy Sciences Laboratory at Texas A&M University and is made possible by the integration of utility systems and some A number of airports noted the creation of special programs building systems to allow centralized monitoring and data to guide, implement, and monitor energy efficiency projects. acquisition (Liu 2002). These and other operational strategies that are infrequent or one-of-a-kind as identified by respondents are noted in this The Continuous CommissioningTM process or any similar section. ongoing monitoring program allows staff to discover prob- lems within systems immediately and for those problems to be Maintenance Agreements NO-$ addressed as they occur. This rapid assessment serves to main- tain optimal efficiency for systems and increase preventive One aspect of operations that can assist in achieving reductions maintenance to increase the life of the system. Further, because in energy costs at small airport terminals concerns agents data are constant, energy savings are continuous and ongoing. hired to perform periodic service at their cost on mechanical and electrical equipment and facilities. O&M contracts for low-cost and quick payback measures can include require- Specific actions and operating strategy modifications imple- ments and incentives for energy savings (Sullivan et al. 2004, mented through the Continuous CommissioningTM process at p. 3.6; PECI 1999a, p. 13). Quite often these incentives will DFW included equipment staging, temperature and pressure cause contractors to utilize re-commissioning measures to reset, and modified operating schedules. secure incentives. Cost/Payback/Savings: Because Continuous Commis- Tampa International Airport (TPA) and DFW noted using sioningTM is dependent on both BAS and advanced metering maintenance agreements to aid in the implementation of energy technologies, as well as requiring significant staff support, it efficiency practices. Data did not indicate if these agreements is mentioned for information and not as a low-cost strategy. were with energy service companies. Energy efficiency benefits resulting from continuous com- missioning were reported to be significant with more than Cost/Payback/Savings: This action was identified as a $3 million in measured and verified energy savings over a no-cost improvement with immediate payback. 5-year period by DFW. In studies of this assessment method outside the DFW facility, it was reported that following imple- Preventive Maintenance Programs NO-$ mentation, "the average measured utility savings are about 20%, with simple paybacks often in less than two years" (Liu Survey respondents and literature reported the implementa- 2002, p. 1.1). A 2006 DOE study indicates savings of up to tion of various programs within operations to improve energy 45% yearly energy costs from an "ongoing commissioning efficiency and reduce costs. program" (Sullivan et al 2007, p. 8.3). Document O&M procedures--The documentation of "O&M procedures in a centralized manual reduces dependence on individual specialized knowledge or Box 9 An Important Part of Continuous Commissioning: expertise regarding airport systems" (Turner et al. Baseline Models 2007, p. 10). Once the commissioning scope has been defined and a Whole system maintenance such as light fixture clean- preliminary audit is performed, it is necessary to document ing and bulk re-lamping or window cleaning. existing conditions or create what is known as a performance Seasonal review of O&M strategies and schedules to baseline model in order to determine energy savings follow- fit climatic variations (PECI 1999c, p. 4). ing commissioning. Cost/Payback/Savings: Because these programs are already Baseline models can be developed data gathered over variable part of the operations budget, no additional cost is incurred. periods of time including "short term measured data obtained Payback information varies, however, as noted elsewhere, from data loggers or the EMCS system" and "Long-term operational improvements initiated by staff often have a pay- hourly or 15-minute whole-building energy data, such as back of less than 1 year. whole-building electricity, cooling and heating consumption, and/or utility bills for electricity, gas and/or chilled or hot water" (Liu 2002, p. 1.6). Box 10 Energy Service Company Contract Collecting short-term data for a baseline is usually more eco- nomical than collecting long-term data; however, "long-term Energy service companies (ESCOs) provide performance data often produce additional savings, making them the pre- based services with compensation relating directly to energy ferred data type." (Liu 2002, p. 1.7) saved. See chapter two for more information on ESCOs.

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19 Temporary Settings/Mothballing $ Box 11 MSP Metropolitan Airports Commission When airport facilities are underused or unoccupied, plans STAR Program can be in place to shut down or mothball nonessential sys- At Minneapolis/Saint Paul International Airport (MSP), the tems to reduce energy use. One survey respondent reported Metropolitan Airports Commission (MAC) has implemented that "due to flight reductions we have closed off one con- a comprehensive sustainability program entitled Stewards of course to reduce heating, cooling and lighting." Others noted Tomorrows Airport Resources (STAR) (see Figure 5). Energy "semi-mothballing unoccupied or under-occupied facilities"; efficiency components of the program, noted as "MAC and "baggage and security system temporary shutdown when ACTION" have included the following: activity is reduced." By shutting down boilers during the summer months, Montgomery Regional Airport (MGM), Installed ground power and pre-conditioned air at gates Montgomery, Alabama, indicated that natural gas expenses Implemented annual energy conservation projects dropped 50%. Installed energy-efficient lighting Implemented day-lighting window design Literature described setup and setback strategies for build- Implemented automatic lighting controls ing temperature settings during nighttime operations that Utilized automatic HVAC settings and controls sets high and low limits for cooling and heating systems to Upgraded both hot and chilled water central plants. reduce HVAC cycling when spaces are unoccupied (PECI (Metropolitan Airports Commission 2009) 1999c, p. 23). Costs/Payback/Savings: The cost of shut down or moth- balling spaces can be quite low if BAS control is used. Pay- Interviewees noted that this comprehensive program, which back for nighttime temperature settings is often less than one addresses aspects of energy conservation and renewable energy year (PECI 1999c p. 23). as well as eight other categories has been essential in promot- ing a "culture of sustainability" begun by the MAC Energy Conservation Program in 1998. Energy Efficiency Specific Project Criteria $ - $$ Many survey respondents indicated that design and construc- tion standards at their facility include aspects of energy effi- ciency. Others noted the used of payback or return on invest- ment (ROI) criteria for any efficiency-oriented improvements. One benefit of implementing nationally recognized stan- dards is that staff or consultant time is saved by not having to develop standards; however, national scale programs have limitations when applied to unique climatic conditions such as temperature extremes or programmatic requirements of airport terminals and often have rigorous documentation requirements. Standards are referenced in chapter two. Cost/Payback/Savings: If standards exist, no cost. If national rating systems are referenced, again costs can be low. Airport Sustainability Programs $ - $$ - Fostering an operations culture that supports energy efficiency will garner long-term commitment to improvements from staff and airport users alike. In 2007, MSP instituted a comprehensive, airport-wide program to promote sustainability and stewardship of airport resources. This program notes in its vision statement that "being good stewards means operating and developing our FIGURE 5 Culture of sustainability. An informational document airports in ways that meet the needs of the present without for Minneapolis/St. Paul International Airport sustainability compromising the ability of future generations to meet their program: Stewards of Tomorrows Airport Resources. own needs" (Metropolitan Airports Commission 2009). (Courtesy: MSP Metropolitan Airports Commission.)

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20 Personnel/Human Factors Box 12 Communications: Cultivating a Culture A major aspect of making effective changes to operations prac- of Conservation tices for energy cost reduction involves personnel and their Communication is an important tool on multiple levels: attitudes toward energy efficiency. As noted earlier in the spe- Intranets, newsletters, and other means of disseminating cial programs section, creating a "culture of sustainability" information among airport staff, airlines, and other tenants within the airport operations department and across airport and are very useful in educating the people that inhabit the air- tenant staff will ensure that programs and practices are imple- port on a daily basis about the benefits of energy efficiency mented and followed. Indeed, DFW noted that after multiple programs, and the impact that their individual actions can presentations about the airports' energy conservation program have on energy efficiency and other environmental pro- to tenants and staff ideas for improving energy efficiency are grams. Some airports reported success expanding commu- now being generated outside of operations. nication efforts into related programs, including employee carpooling at DFW, and alternative work schedules at The Hawthorne Effect NO-$ Tampa International Airport (TPA), where some employ- ees work four 10-hour days, decreasing their commuting The Hawthorne Effect references an early 20th century study costs by 20%. of workers at the Hawthorne Plant of the Western Electric Company in Cicero, Illinois. Findings from that study indicated that the behavior of workers may be altered in a positive direc- sonnel and stakeholders. This communication can take many tion when they are aware of the study. forms and use multiple channels within airport operations and public-use areas. It can also be as simple as a sticker on As energy efficiency improvements are initiated (espe- a light switch suggesting that lights be switched off when cially ones that increase monitoring of energy use such as sub- exiting the room (CAP 2004). metering) small gains in efficiency can be expected when personnel are aware of the improvement, owing to the Information sharing in the form of a monthly newsletter Hawthorne Effect (Clark 1999). was used at one large airport interviewed. This communica- tion strategy has proven to raise awareness about energy effi- Training $ ciency issues and provide savings through vigilance on the part of O&M staff. At another airport, energy efficiency pro- A number of airports have implemented "energy awareness" gram staff has made numerous presentations to stakeholder training programs for staff and tenants to raise awareness groups including tenants and are seeing gradual but positive about energy efficiency measures. A limited number have changes in attitudes towards energy efficiency. mandated staff work practices to reduce energy use. Although mandated practices may result in some savings, literature rec- Department of the Interior strategies for raising awareness ommends that management actively "track and measure the suggest "providing mandatory and voluntary training opportu- success of energy-efficiency strategies [and] share energy nities on smart energy practices [and] holding annual energy accounting info with O&M staff to help identify problems fairs before seasonal changes to provide additional informa- and track successful strategies" (PECI 1999a, p. 7). tion for employees about how to manage energy use in the work place and in their homes" (DOI 2006). In addition to awareness training, operations training for O&M staff and day-to-day users of airport equipment, from Additional communications methods include periodic noti- simple thermostats to energy management control systems, fications about turning off lights (see Figure 6), printers, and is crucial to the successful utilization of those energy manage- computers; designating space for energy efficiency informa- ment tools. An example given in a PECI report notes the tion within staff common areas; or drafting monthly or quar- importance of returning controls to original settings. terly informational e-mails about planning, improvements, energy data, or other areas of operations that can affect energy Because many parties, perhaps even tenants, often have access to lighting and HVAC controls, schedule changes to meet special efficiency. needs or unusual conditions may not get returned to their original settings. Over time, these schedules become further and further Communicating about energy efficiency with tenants is removed from matching actual needs (PECI 1999c, p. 21). also important and, as noted in the next chapter with regard to metering data, can be effective in reducing adversarial Communications $ relationships. One interviewee noted the positive effects brought about by communicating to tenants that some air- For the Hawthorne Effect to take place, information about port fees had not increased for five years because of energy energy cost-reduction practices must be distributed to per- efficiency projects.

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21 Upgrade and optimize building automation systems to ensure performance within specifications Calibrate and adjust interior temperatures for optimal occupant, staff, and tenant comfort Utilize building automation systems with motor con- trols for heating, cooling, and conveyance systems. Identify improvements to O&M practices by using sys- tematic assessment for both new and retrofit projects Methods of systematic assessment include energy audits and O&M assessment Multiple forms of commissioning can be used depend- ing on project type and scope. A variety of programs and arrangements are used by airports to guide, implement, and monitor energy efficiency Highlight energy efficiency within new project criteria Utilize temporary settings for underused systems FIGURE 6 Communication with building occupants. Light switch and spaces stickers used to encourage energy conservation at a student Include energy efficiency requirements within O&M dormitory. (Courtesy: Office of Sustainability--Temple University.) service contracts. Human factors can affect the success of energy efficiency Chapter Summary programs Provide targeted training programs for personnel and From the data collected, the following practices were discussed tenants for reducing energy cost and improving energy efficiency Identify communications strategies for creating a within building management and operations at airport terminal "conservation culture" buildings (see Table 1). Psychological effects can provide small savings. TABLE 1 ENERGY EFFICIENCY PRACTICES--BUILDING MANAGEMENT AND OPERATIONS Notes: 1. Payback--time indicated refers to years required for improvement to return cost savings equivalent to project costs. 2. Cost information is based on energy rates for 2009 at respondent airport locations. 3. Cost can be defined as total project cost and not cost per square foot. 4. Percentage--value given represents a yearly reduction in energy or operations costs for that system or process.