Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports (2019)

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60 In this chapter, 15 airport case studies are presented. The case studies appear in alphabetical order by city name. The airports selected for the case studies were chosen to encompass a broad range of sizes, geographic locations, and climate zones, as ambient temperatures have been identified as a significant contributing factor in the use or non-use of electric PCA systems at airports. Figure 17 depicts a U.S. climate zone map (boundaries shown are by state and county), as described in the American National Standards Institute (ANSI)/American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 169-2013 Climatic Data for Building Design Standards. To demonstrate the climatic differences between zones, the graph in Figure 18 displays the annual heating and cooling degree days per climate zone. A degree day is defined as “the difference in temperature between the outdoor mean temperature over a 24-hour period and a given base temperature.” For example, the higher the number of cooling degree days (CDD), the warmer the climate is in that zone. The higher the number of heating degree days (HDD) the colder the climate zone, on average. Generally, a higher number of degree days means that there are more opportunities to condition aircraft air to a comfortable temperature for customers. In these zones, utilization of gate electrification systems is suggested to avoid APU use. 6.1 Hartsfield–Jackson Atlanta International Airport (ATL), Atlanta, Georgia Background Hartsfield–Jackson Atlanta International Airport (ATL) is the busiest airport in the U.S., serving more than 103 million total (enplaned and deplaned) passengers in 2017 (Figures 19 and 19A). Hartsfield–Jackson Atlanta was one of the first airports to develop a sustainable management plan under FAA’s Sustainable Master Plan Pilot Program in 2011. The airport’s original sustainable management plan notes that PCA and ground power connections at air- craft parking positions provide an environmentally friendly alternative to running aircraft APUs. At the time the sustainable management plan was written, the airport had equipped 90 percent of their gates with electric PCA and 400 Hz ground power. Currently, 100 percent of the gates are equipped. The airport has both central and point-of-use PCA equipment. Although utilization is not currently tracked, and the gates are not individually metered, the airport is working to identify possible tracking solutions. While there are almost 30 passenger airlines serving the airport, the majority of market share is accounted for by Delta Air Lines, with almost 74 percent of total passengers (according to the airport’s 2017 December passenger traffic report). Southwest Airlines has the second-highest number of passengers, at just under 10 percent. Gates are leased to the airlines. Although the gate electrification systems are owned by the airport, the airlines are responsible for funding the maintenance, as per the lease terms. C H A P T E R 6 Airport Case Studies

Figure 17. ASHRAE climate zones for U.S. counties (Source: Appendix B, ANSI/ASHRAE Standard 169-2013).

62 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 18. Thermal climate zones as a function of HDD (heating degree days) and CDD (cooling degree days). The colors and numbers in the graph depicted above correspond to the climate zone colors and numbers in the map depicted in Figure 17 (Source: ANSI/ASHRAE Standard 169-2013). Drivers for Installation • Decisions on installation are driven by executive staff and airline needs. • Environmental stewardship is a key driver for installation. Finance Strategy • Finance strategy is set by executive staff. • Gate electrification equipment at Hartsfield–Jackson Atlanta has not historically been funded with VALE grants. Planning and Policy • The Atlanta Department of Aviation consulted with airlines to determine specifications for equipment. • Design and installation of the equipment was a collaborative effort between the Atlanta Department of Aviation, the airlines, and gate electrification equipment manufacturers. • Maintenance of gate electrification systems is handled by a combination of airport staff, air- line staff, third-party service providers, and equipment manufacturers.

Airport Case Studies 63 Figure 19. Hartsfield–Jackson Atlanta International Airport aerial view. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 2A, Hot/Humid Large hub, primary, commercial • Passengers (total): 103,934,417 • Passenger growth (2016–2017): -0.23% • Cargo weight: 691,269 metric tons • Cargo growth: 6.58% • Number of passenger airlines serving: 29 2017 data provided by the airport • There are 194 operational gates, all airport owned. • All gates are equipped with electric PCA and 400 Hz ground power. • The airport has both central and point-of-use systems. • There are some airline-owned mobile diesel units. • There are four hardstands that are not in use as of 2018. • Utilization rate is not tracked (electricity use included in concourse power feed). Major Tenants Regulatory Issues • Passenger airlines: Delta Air Lines, Southwest Airlines, and ExpressJet • Cargo: FedEx, United Parcel Service (UPS), and Delta Air Lines Carriers with greatest market share listed • VALE status: Eligible • Current NAAQS status: Maintenance zone for PM2.5 and moderate zone for ozone (8-hour) • VALE participation: VALE grants for compressed natural gas vehicle projects (2012, 2013, and 2014). No gate electrification system components funded through VALE. Figure 19A. Hartsfield–Jackson Atlanta International Airport specifications (PM2.5 refers to particulate matter). • The airlines are responsible for disseminating any company policies with regard to electric PCA and ground power use to their employees. • No formal tracking system is in place for tracking maintenance work orders or job prioritization. Tracking and Data Collection on Utilization • No utilization data collection system is in place, but the airport is considering options to implement one. • Gates are not individually metered. • The Atlanta Department of Aviation has no policies requiring or encouraging the use of gate electrification equipment.

64 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Lessons Learned and Best Practices • Maintenance staff and ground handling crews are trained on proper equipment use by the equipment manufacturers. • The building management system is occasionally used to notify carrier and airport staff about equipment outage or failure. • The majority of gates are leased to one airline, which reduces the variability in ground crew training regimens and airline policies. 6.2 Boston Logan International Airport (BOS), Boston, Massachusetts Background At Boston Logan International Airport, all of the 94 operational gates are equipped with electric ground power units, and 87 out of 94 gates are equipped with electric PCA (Figures 20 and 20A). There are a number of remote hardstands in use for both passenger boarding and overnight aircraft parking, which are serviced by gas and diesel powered mobile PCA and ground power units. While airlines and airport staff report observing high PCA and GPU usage, the weather and climate at Boston Logan create some utilization challenges for PCA systems. Due to the extreme cold in the winter, airlines report that the PCA systems are unable to provide sufficient heat for cabins of certain aircraft models when the outside temperature is below 20°F. In these condi- tions, the pilots turn on the APUs to maintain passenger comfort. Utilization at Boston Logan can also be impacted by high wind events. During these conditions, operators do not connect to PCA systems and instead use APUs because PCA hoses may become unsecured and lead to safety issues on the apron. Heat during summer months in Boston was not identified as a significant challenge to the use of PCA; however, one airline identified difficulty in maintaining comfort- able cabin temperature during summer months for a specific aircraft type due to the location of the air intake. In general, airline and airport staff reported that electric PCA and GPU utilization is high, despite not having equipment in place to conduct systematic monitoring and tracking (with the exception of VALE-funded equipment, which is monitored to estimate emissions reductions). Utilization seems to be more consistent when airlines have exclusive use of the gate(s) and use in-house maintenance staff. The importance of proper education and training of ground crews, as well as preventative maintenance, was emphasized. Drivers for Installation • While regional air quality has improved, consistent community focus on air quality helps drive continuous improvement by Massport and stakeholders. • In public environmental documents, Massport regularly reports on the air quality benefits of the use of gate electrification systems. • Emissions reductions realized from installation and use of electric PCA and GPU can eliminate—or reduce—the need to offset emissions of construction projects to comply with the Massachusetts State Implementation Plan for air quality. • The use of electric PCA and GPU results in reduced fuel use and maintenance costs associated with reduced APU cycles, which helps justify the cost of installation.

Airport Case Studies 65 Figure 20. Aerial view of Boston Logan International Airport. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 5A, Cool/Humid Large hub, primary, commercial • Passengers: 38,412,419 • Passenger growth: 5.9% • Cargo weight: 679,407,977 lbs. • Cargo growth: 10.10% • Growth: 2.6% in total operations • About 40 airlines serve the airport. Statistics reflect 2017 data reported by Massport. • There are 94 operational gates. • There are 87 gates equipped with electric PCA. • There are 94 gates equipped with electric GPU. • Hardstand operations are serviced by mobile diesel- and gasoline-powered PCA and GPUs. • VALE-funded equipment is tracked for estimating emissions reductions; however, utilization rate is not systematically tracked. • Equipment ownership is mixed. Major Tenants Regulatory Issues • Passenger airlines: JetBlue Airlines, American Airlines, Delta Air Lines, United Airlines, Southwest Airlines, Air Canada, Alaska Airlines, British Airways, and Lufthansa • Cargo: FedEx, Quantem, Swissport, UPS, and Worldwide Flight Services • Current NAAQS status: Maintenance zone for CO • VALE participation: $2,000,000 (FY 2013) for PCA and ground power units for eight gates and $2,000,000 (FY 2018) for 50 electric charging stations for electric ground support equipment. Also received $5,974,017 for 18 CNG and 36 electric/diesel hybrid buses in FY 2010. • Massport voluntarily publishes annual emissions inventories for criteria pollutants and greenhouse gases. Figure 20A. Boston Logan International Airport specifications (CNG = compressed natural gas).

66 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Finance Strategy • Gate electrification equipment ownership is mixed. Some components are owned and financed by the airport; others by the airlines. • Massport funded the purchase and installation of PCA and GPU equipment for eight gates with a VALE grant. Remaining systems were obtained through a combination of airport capital program funding and airline funding. • One airline noted that investment in new systems is tied to oil prices, and when fuel prices are high it is easier to justify installation of PCA and GPU equipment. Planning and Policy • Massport does not have a formal policy requiring airlines to use gate electrification equipment. • Airlines that participated in the case study interview reported having their own policies that require the use of gate electrification systems when available (though pilots ultimately have control over when to use the aircraft APU). Tracking and Data Collection on Utilization • Due to use of equipment in older buildings without submetering, utilization data for electric PCA and GPU are not systematically tracked; however, annual use data (hours of run time) for electric PCA and GPU equipment purchased with VALE grant funds must be recorded so that emissions reductions can be estimated. • Some gates are equipped with an electric meter, and Massport plans to install meters when replacing or building new gates. However, there are no plans to retrofit existing gates with meters. • Some airlines pay for electricity use based on actual use; others pay as part of rates and charges. • One airline noted that they have an internal reporting requirement with regard to APU fuel use compared to fuel targets. When targets are not met, airline management investigates the contributing factors. • Some airlines track all maintenance calls via a SharePoint site for each of their gates. The information is evaluated and tracked to determine if the maintenance issue is with the equipment or the aircraft. Lessons Learned and Best Practices • One airline reported using LED sensors to measure the temperature of air from the PCA hose output to monitor performance. • Preventative maintenance and quality control for gate electrification systems and components are useful to address problems before they cause equipment to malfunction. • Training and communication on equipment operation are critical to combat equipment damage from misuse, particularly related to proper disconnection procedures. – When fuel prices were higher, the training and education focus was on quick and correct connection of PCA and GPU, with less focus on proper disconnection. • Simple technology solutions can address common problems that cause damage and sub- sequent unavailability of equipment. For example, the use of locking and hooking procedures to secure power cables can help prevent cables and PCA hose reels from being run over. • Anecdotal evidence suggests that utilization rates are higher on gates that are leased exclusively to one airline. There appears to be an opportunity to increase gate electrification system utilization through development of best management practices and standard operating procedure manuals where gates are not for exclusive use, as in Terminal E.

Airport Case Studies 67 • Collaboration and coordination between airlines and airports is important in: – System design, funding, grant applications, and acquisition decisions; – Development of team approaches to operating and maintaining equipment; – Reporting on performance and outcomes to address issues, solve problems, and establish new best practices. 6.3 Burlington International Airport (BTV), Burlington, Vermont Background Burlington International Airport in Burlington, Vermont, is classified by FAA as a small hub airport, with just under 600,000 enplaned passengers per year (Figures 21 and 21A). There are 11 operational gates, which are owned by the airport, with preferential-use leases for tenants. Nine jet bridges are equipped with electric ground power, but only five are equipped with electric point-of-use PCA units (four are airport owned; one is airline owned). The airport- owned ground power and PCA units are not individually metered and, therefore, utilization is not tracked. There are also two remote, remain-overnight parking positions that are served by airline-owned mobile diesel- or gasoline-powered PCA and GPUs. Burlington International is located in ASHRAE Climate Zone 6A (primarily cold and humid). According to the National Weather Service Forecast office, the city of Burlington has a mean average January temperature of 18.7°F and a mean average temperature for July of 70.6°F. Over- all, the airport reports minimal challenges to utilization presented by extremely cold winter weather, but there are some considerations. For example, airlines serving Burlington Interna- tional face some challenges with regard to APU use in the winter months, particularly overnight when heating demands of the aircraft can exceed gate electrification equipment capabilities. Also reported to occur periodically, the airport-owned jet bridge wheels get stuck in the snow or on ice on the apron. To address this issue, maintenance staff have implemented a best practice of using covers to protect gate electrification assets and certain parts of the motors from weather. Other best practices include the use of equipment that keeps the PCA hose off the ground while it is being rolled up, which prevents the hose from freezing to the ground in the winter. Keeping the hose off the ramp also slows the loss of heated air (in the winter) and the loss of cooled air (in the spring and summer) to the ramp. Preventative maintenance and routine maintenance calls are handled internally by airport staff for the airport-owned gate electrification equipment. The PCA equipment is serviced by a third party contracted by the airport. The airline-owned gate is also serviced by a contractor. Due to the age of the systems, spare parts availability is an issue, and there is often a long lead time for replacement parts. In some cases, the original manufacturer no longer makes spare components for the type of units in place, leading to delays in system repair and impacting utilization rates. In general, the airport reports that their maintenance budget is sufficient to maintain systems without stresses on resources. Communication between the airport and airlines with regard to the status and availability of equipment is somewhat informal but effective. Airlines are required to notify airport operations staff of any issues with the equipment. A work order is then created, and maintenance staff is notified. Once the system is fixed and operational, the airport electricians or third-party contrac- tor will notify airport operations and airlines. The airport strives to communicate the status of equipment directly to airline station managers. The most common reasons cited for aircraft APU use include when the gate electrification equipment is inoperable, when there is a miscommunication between the airline crew and

68 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 21. Aircraft takeoff at Burlington International Airport. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 6A, Cold/Humid Small hub, primary, commercial • Enplaned passengers: 591,558 • Passenger growth: -2.15% • Number of passenger airlines serving: 6 • There are 11 operational gates. • Gates are assigned through preferential-use leases. • Nine jet bridges are equipped with electric GPU. • Five jet bridges are equipped with both electric PCA and electric GPU. • Four PCA units are airport owned; one PCA unit is airline owned. • Diesel-powered mobile PCA carts are used for gates without electric PCA and for two remain- overnight parking positions. • Gate electrification system utilization is not tracked by the airport. Major Tenants Regulatory Issues • Passenger airlines: American Airlines, Delta Air Lines, Frontier, JetBlue Airlines, Porter, and United Airlines • Cargo: Wiggins Airways and FedEx • Fixed-base operators: Heritage Aviation • VALE status: Not eligible • Current NAAQS status: In attainment Figure 21A. Burlington International Airport specifications.

Airport Case Studies 69 ground crew about equipment availability, and when such miscommunication occurs when systems are connected to the aircraft. An example of this miscommunication includes when a ground crew member connects the PCA and GPU but the pilot leaves the APU running, even if the PCA is sufficient to heat or cool the aircraft. Drivers for Installation • Airlines were supportive of new gates being equipped with electric PCA and GPU when the terminal was built. • Community is environmentally aware and was supportive of gate electrification system investments. Finance Strategy • Cost of gate electrification equipment was part of the capital project when the terminal was built. • Most airlines do not pay for electricity based on specific usage, as PCA and GPU equipment is not individually metered. Electricity fees are built into rates and charges. – One airline is billed for electricity usage for their own PCA and GPU at one gate. – Airlines receive a bill for fuel usage of mobile units. • As older jet bridges are replaced, they will include both electric PCA and GPUs. However, financing has not yet been determined for the end-of-life replacements. Planning and Policy • Airport plans to equip future jet bridges with electrification systems as older ones are replaced. • One airline reported a company policy that requires the use of electric PCA and ground power, when available, at their gate in place of aircraft APUs. This airline’s policy also requires that aircraft be connected to external ground power within a certain maximum time frame after parking at a gate and that external ground power not be disconnected prematurely prior to aircraft departure. Tracking and Data Collection on Utilization • Airport-owned equipment is not metered, and utilization data for electric PCA and GPU are not systematically tracked by airport. • Airline-owned gate equipment is metered. – Electricity usage is tracked by monthly kilowatt hours and average kilowatt hours used per day for both the PCA and GPU. – Airline reports tracking spikes in electricity usage on extremely hot or extremely cold days or when power is needed overnight. – Airlines receive bills for diesel fuel for mobile PCA and GPUs and track total fuel use. • One airline reported receiving an APU utilization report weekly. The airline aims for a certain maximum amount of time of APU use per aircraft when parked. The airline investigates cases where APU use is higher than expected. • The airport tracks diesel fuel used in portable units. They have individual bills for diesel and for unleaded fuel purchased from fixed-base operators. Lessons Learned and Best Practices • Accurate historical maintenance data on all systems are useful for ensuring that spare parts are on hand, for determining which system components need repair more frequently, and for understanding the expected life span of equipment better.

70 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports • If airport electricians cannot identify the cause of a broken GPU, the crew will check whether the system is operable for the next aircraft to verify whether it is an issue with the GPU or if the problem originated at the aircraft connection. If the latter, the airport notifies the airline. • The ground crews are generally well trained and experience low turnover. • Airlines perform daily equipment inspection with a checklist, and staff will tag any equip- ment that is out of service to allow for easy visual identification of equipment status. 6.4 Dallas–Fort Worth International Airport (DFW), Dallas, Texas Background Dallas–Fort Worth International Airport is the fourth busiest airport in the U.S. (based on 2017 passenger numbers), with 28 passenger airlines serving more than 67 million pas- sengers, the majority of which were carried by American Airlines (more than 85 percent) (Figures 22 and 22A). The airport has 165 gates, of which 111 are owned by the airport and the remainder are airline owned. All gates have electric PCA and ground power equipment (both central and point-of-use) (Figure 23). A number of gates were equipped with elec- tric PCA and ground power with the assistance of VALE grants. In addition to having very comprehensive environmental and sustainability goals, the airport is located in a NAAQS nonattainment zone for ozone and is motivated to reduce both local air-pollutant emissions, as well as greenhouse gases. Despite achieving 100 percent equipage of gates, only the newest gates are individually metered with electrical meters. The airport does not have a formal utilization tracking process in place. However, hours of run time are tracked for VALE-funded equipment. Airport staff observations indicate that utilization is generally high, but the airport experiences some challenges with gate electrification system utilization. First, some gates have equipment that is at the end of its useful life, thus, requiring more maintenance and resulting in decreased reliability. Second, some PCA units are not right-sized, which means that they do not have sufficient capacity to condition the aircraft size presently operating at the terminal gate, particularly the Boeing 777. Another challenge occurs when the central PCA system transitions from the heating season to the cooling season or vice versa. During the shoulder seasons, there are days when actual temperatures create the need for either continued heating or cooling (i.e., the opposite need of that which the system has been configured for that month). This condition may occur multiple times during an operational day or for multiple days during the transition from one season to another. Whenever this type of condition exists, airlines rely on APU utilization to address the cooling or heating needs of the aircraft, as appropriate. Finally, there are some hardstand positions (not connected to the terminal) that are used for regular passenger loading and unloading. These positions are not equipped with electric PCA or electric ground power, which results in aircraft using APUs or airlines using mobile, diesel- powered units for heating, cooling, and power. The airport and airline staff interviewed during the research considered the cost of installing electrical power at a hardstand to be prohibitively high. However, when considering these costs the financial model should take into account the longer life span associated with electrical infrastructure and wiring as opposed to the shorter useful life of mobile PCA and ground power equipment. One airline is performing a study on current PCA and GPU utilization and the operational condition of each unit at Dallas–Fort Worth International. The airline intends to identify and address maintenance issues with regard to each PCA and GPU unit, including their capacity and

Airport Case Studies 71 Figure 22. Dallas–Fort Worth International Airport aerial view. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 3A, Warm/Humid Large hub, primary, commercial • Total passengers: 67,092,224 • Passenger growth: 2.30% • Cargo weight: 894,204.1 U.S. tons • Cargo growth: 7.80% • Number of passenger airlines serving: 28 2017 data provided by the airport. • There are 165 operational gates. • There are 111 gates owned by the airport, all equipped with electric PCA and electric GPU. • There are 54 gates owned by airlines, all equipped with electric PCA and electric GPU. • PCA includes point-of-use and central systems. • 24 airport-owned, diesel, mobile GPU and/or PCA units are used for corporate aviation and when electric units fail. Additional mobile units are owned by airlines to service remote hardstands, which are not equipped with electric PCA or ground power. • Utilization rate is not systematically tracked, though newer gates are individually metered. Major Tenants Regulatory Issues • Passenger airlines: American Airlines, Delta Air Lines, Spirit, and United Airlines • Cargo: Federal, United Postal Service, and DHL Carriers with greatest market share listed. • VALE status: Eligible • Current NAAQS status: Moderate nonattainment for ozone • VALE participation: $3,065,946 (FY 2016) for ground power at 23 gates and PCA for five gates; $2,000,000 (FY 2014) for ground power and PCA at 12 gates Figure 22A. Dallas–Fort Worth International Airport specifications. reliability, as well as the condition of various components, such as air handlers, hoses, and power cables. The intention is to identify gates suitable for parking Boeing 787s. Drivers for Installation • To demonstrate industry leadership and to help meet environmental goals • Air quality regulatory concerns and state and local regulatory considerations • To satisfy customer service standards and expectations • By request from airlines or tenants • Availability of grant funding

72 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Finance Strategy • Utilize FAA VALE grants. • Leverage capital improvement program funds. • Seek airline investment. Planning and Policy • Preventative maintenance program ensures maintenance is performed in advance to maintain system availability (i.e., functionality throughout the operating day). • Dallas–Fort Worth International encourages airlines to use electric PCA and ground power at gates (Dallas–Fort Worth International Airport 2018). • The airport charges airlines for electricity through terminal rents; not actual usage. Tracking and Data Collection on Utilization • Jet bridges are not individually metered, but newer gates are equipped with individual electric meters. • To increase utilization, the airport is considering implementing a system to provide visual notification to pilots when their aircraft is connected to PCA. Lack of visual indicators that denote when aircraft are connected to the PCA can result in pilots continuing to run the APU. However, there are visual indicators when aircraft are connected to ground power. • Informal observation-based utilization tracking has resulted in findings that indicate that— while utilization rates are high overall—there are a number of challenges. – Older equipment on some gates is unreliable, requiring frequent maintenance. – Equipment not right-sized for all aircraft results in aircraft using APUs. For example, PCA hoses and GPU power cables are not the correct length, or PCA units are not powerful enough for larger aircraft, particularly when ambient temperatures are very high. – Centralized PCA systems are programmed to switch from heating to cooling with seasonal changes rather than being readjusted daily, resulting in aircraft running APUs during shoulder seasons when the PCA temperature is either too warm or too cool to effectively condition the aircraft cabin based on ambient temperatures. – Ground crew misuse of equipment causes damage to component parts, which results in out-of-service equipment. • Aircraft must use APUs or mobile, diesel-powered PCA and GPUs when parked at hardstands or maintenance facilities. Figure 23. Aircraft connected to electric PCA and 400 Hz ground power ( left) and PCA hose and basket (right) (Source: Katherine Preston, Harris Miller Miller & Hanson, Inc.).

Airport Case Studies 73 Lessons Learned and Best Practices • Maintenance personnel are responsible for a variety of systems, including PCA, ground power, jet bridges, and baggage-handling systems. Often, when there are competing mainte- nance demands, jet bridges and baggage systems will receive priority, which results in longer outages for the PCA and ground power systems. Insufficient resources and/or prioritization of maintenance of these systems can result in extended critical system outages and aircraft utilizing APUs more frequently. • In addition, maintenance personnel who also maintain IT systems place a higher priority on ensuring that critical ramp systems, such as ADP Safegate SafeDock, are available, particularly during periods of electrical storm activity. • Newer aircraft, particularly Boeing 787s, require additional power due to advanced avionics. Such technology requires the replacement of existing serviceable, but undersized, gate electrification equipment to match system capabilities with the type of aircraft being serviced. • The implementation of one-time digital combination locks on equipment allows the airport to keep track of individual ground crew members’ use of gate electrification equipment; thus, providing accountability if damage occurs. • Ribbed hoses are effective at preventing hose kinks, and insulated PCA hoses are more effec- tive at keeping the air cool (or warm) as it is delivered to the aircraft. • Hose reels and hose extension bins assist the ground crew in dispensing the proper length of PCA hose. • Development of clear reporting responsibilities, as well as visually tagging items when equipment is out of service, is important for prompt response and elimination of redundant maintenance action requests. • Consistent and adequate training of ground crew on proper operation and use of gate electrification equipment can be difficult because of high staff turnover. • Companies that provide contracted ramp services to multiple airlines must comply with multiple standard operating procedures, which creates training challenges. 6.5 Denver International Airport (DEN), Denver, Colorado Background The Denver International Airport is a large hub airport, and—with its opening in 1995—one of the newest airports built in the U.S. (Figure 24). The airport currently has 116 gates with jet bridges, and six ground-load gates (Figure 24A). All are equipped with electric PCA and 400 Hz ground power, and it is standard operating procedure at Denver International to have gate electrification systems available at all gates. While utilization of these systems is not formally tracked, airport staff report that airlines consistently hook aircraft up to the equipment almost immediately upon arrival at the gates. Thirty-nine new gates are planned to accommodate projected airport growth, and there is an active gate replacement program in place for older equipment. Power requirements are assessed for both new and replacement gates to meet the needs of newer aircraft, such as the Boeing 787. This assessment ensures adequate electrical load to heat, cool, and power larger aircraft and those with more advanced onboard avionics systems. Of the 39 new gates, four are planned to accommodate wide-body aircraft (e.g., Boeing 747s), and the remaining 35 are planned to accommodate narrow-body aircraft (e.g., Airbus 321s and Boeing 737s). The airport has a lim- ited number of gates equipped with 28-volt power for smaller regional jets. Equipment that was purchased with VALE grant funds are equipped with hour meters to track emissions reductions. These hour meters track the amount of time the equipment is in use but

74 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 24. Denver International Airport terminals. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 5B, Cool/Dry Large hub, primary, commercial • Total passengers (2017): 61,379,396 • Passenger growth: 5.30% • Number of passenger airlines serving: 23 Data from airport’s 2017 Passenger Traffic Report • There are 116 gates with electric PCA and GPU, all owned by the airport. • There are six ground-load gates for narrow-body aircraft equipped with electric PCA and ground power. • There are 20 hardstands for remain-overnight positions served by airline-owned, mobile, diesel-powered PCA and GPUs. o A few remain-overnight positions have electricity available but no electric PCA or ground power provided. • Both centralized and point-of-use PCA systems are in place. • Individual PCA units are equipped with hour meters for tracking hours of use to estimate emissions reductions. • PCA and ground power systems are not equipped with individual electrical meters. However, all new and replacement gates will have electrical meters. • Utilization of gate electrification equipment as a function of actual use versus total possible use is not systematically tracked. Equipment at 39 future gates will be individually metered. Major Tenants Regulatory Issues • Airlines with greatest market share: United Airlines, Southwest Airlines, and Frontier • Cargo carriers: World Port Cargo Support, DHL, FedEx, UPS, and United Airlines Cargo • Current NAAQS status: Moderate nonattainment for ozone (8-hour), Maintenance zone for CO and PM10 • VALE participation: Total of $1,889,674 in VALE grants awarded for PCA and GPU equipment in FY 2014 and 2018 (16 PCA units and 32 GPUs were funded with VALE grants). Figure 24A. Denver International Airport specifications.

Airport Case Studies 75 not electricity consumption. While the airport does track use of VALE-funded equipment and calculates estimated emissions savings from these data, the airport does not systematically track utilization of their gate electrification systems (i.e., the amount of time the equipment is in use compared to the amount of time the equipment could potentially be in use). The airport has recently adopted new design standards that require all new and replacement gates to be equipped with individual electrical meters. A motivation for this change was to receive additional Leadership in Energy and Environmental Design, or LEED, credits for these future projects. The airport utilizes the Honeywell Enterprise Building Integrator platform as an energy management system. Currently, the platform is primarily used to monitor the HVAC system. But in the future, the airport plans to integrate other systems as additional submeters are installed. Airport staff maintains the gate electrification systems. They use a system known as mainte- nance control for airlines to report any equipment outages or failures, enabling round-the-clock maintenance coverage of the system. Occasionally, third-party service providers are brought in for major issues, but in-house staff are normally equipped to repair any problems. Maintenance staff will coordinate with airport operations staff and the airlines. The airport also keeps backup ground power and PCA units in stock to install during systematic maintenance. Reliability is ensured via a preventative maintenance program, which is completed by a specialized team at night or during off-peak hours so that daytime operations are not disrupted. The airport attributes the high (observed) utilization rate to universal equipage of gates, a reliable in-house maintenance and replacement program for jet bridges and gate electrification equipment, proper training and communications protocols, and airline policies. Drivers for Installation • Initial equipage was undertaken as a standard operating procedure to provide a service to the airlines and to demonstrate proactive environmental management and industry leadership and positive community. • Bridge replacement is conducted based on changes in fleet composition (i.e., size and type of aircraft) and passenger volumes. • Airlines are supportive of the airport’s efforts to fund some of the equipment with VALE grants. Finance Strategy • Electric PCA and ground power systems were included in the initial construction of the air- port, and the electrical system was designed for growth (i.e., the electrical system can handle the additional capacity of new gates and electric PCA and ground power). • Subsequent equipment installation leveraged FAA VALE grants in 2014 and 2018. • Electricity costs are built into airline rates and charges. Individual pieces of equipment are not metered and, therefore, it is not possible at this time to break out airlines’ actual electrical use. Operation, Maintenance, and Training • The airport owns and maintains all the PCA and ground power equipment to ensure avail- ability, reliability, and consistency. – Airport maintenance and electrical staff stock spare PCA and ground power units to keep equipment available when units need to be removed for repair or replacement. – Preventative maintenance on jet bridges and components is conducted by teams at night and during off hours to minimize time out of service. – Airport staff normally have capacity to repair units during the operational day.

76 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports • Maintenance budgets and staffing levels are sufficient to maintain equipment and to quickly repair damaged units. The airport has an active, well-planned jet bridge replacement pro- gram for equipment that has reached end-of-useful life (i.e., average three to four replace- ments per year). • Airport staff will train one to two staff from each airline on the proper operation of gate electrification equipment or arrange for a manufacturer to provide training. The airlines are then responsible for training their own ground crews. This process results in a well-trained ground crew. Planning and Policy • Airport standard operating procedure is to supply PCA and ground power at all gates and ensure that the equipment is reliable and in good working order. • No official language exists in airline leases that requires the use of PCA and GPU, but the airport noted that all carriers have their own policies concerning PCA and ground power use. • Active jet bridge replacement program: – Equipment generally has a 20-year life span. – Station managers are involved in the phasing schedule for installing and replacing new units to ensure minimal downtime. – Airlines are involved with developing the replacement schedule. Early coordination is key to establishing proper timelines and planning gate use during construction periods. Tracking and Data Collection on Utilization • Utilization is not formally tracked, and equipment is not metered. However, new design stan- dards require individual metering, and meters will come standard on 39 new gates. • The airport uses a building energy management control system, primarily for managing HVAC systems. The airport plans to incorporate other systems over time but is not yet at the point of integrating PCA or ground power systems. • Informally, airport staff have observed a high utilization rate, and airlines plug in immediately upon arrival at gates. Lessons Learned and Best Practices • Some PCA units are too large to serve the aircraft. If the aircraft only has one portal but the PCA unit has two ducts, connection may not be viable. • Airports should consider new aircraft models coming online—such as the Boeing 737 series— to ensure that they can handle the electrical demand of large aircraft. • Occasionally, equipment is damaged by ground crews pre-staging the power cables or PCA hoses in anticipation of an aircraft’s arrival at a gate. 6.6 Kansas City International Airport (MCI), Kansas City, Missouri Background Kansas City International Airport is a medium hub airport located in a mixed climate zone (i.e., warm summers and cool winters) (Figures 25 and 25A). The airport currently consists of two separate terminals (B and C), while construction of a new, unified terminal is under way at the site of the previous Terminal A. When complete, the new terminal will replace the exist- ing terminals. Currently, all gates at Kansas City International have jet bridges that are each

Airport Case Studies 77 Figure 25. Aerial view of Kansas City International Airport terminals. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 4A, Mixed/Humid Medium hub, primary, commercial, reliever, military • Total passengers: 11,503,936 • Passenger growth: 4.19% • Cargo weight: 198,491,890 lbs. • Cargo growth: -2.63% • Number of airlines serving: 11 2017 data provided by the airport. • There are 35 operational gates, which are owned by airport and leased on exclusive-use basis to airlines. • All gates are equipped with electric PCA and 400 Hz ground power; all are point of use. • A few gates have 28-volt power. • Airlines own mobile, diesel-powered PCA and GPUs to provide air and power to aircraft at remain- overnight parking positions or if PCA and ground power is out of service. • Gates and equipment are not individually metered, and utilization rates are not tracked. • Proactive maintenance practices ensure high reliability. Major Tenants Regulatory Issues • Passenger airlines: Southwest Airlines, Delta Air Lines, American Airlines, and United Airlines • Cargo: FedEx and UPS Passenger and cargo carriers with greatest market share listed • VALE status: Not eligible • Current NAAQS status: Attainment Figure 25A. Kansas City International Airport specifications. equipped with 30-ton ambient air PCA units (480V Jetaire) and 400 Hz ground power. The airport’s proactive maintenance program ensures that jet bridges and gate electrification equip- ment are highly reliable with minimal downtime. The airport owns and maintains—through the on-site, third-party contractor ABM—all of the jet bridges, including the gate electrification equipment (Figure 26). The airport and their maintenance contractor have found that preplanning for maintenance is critical to maintaining a high level of availability of gate electrification equipment, and they provide sufficient budgets to facilitate this. Because the terminals are not connected, and airlines have exclusive-use lease agreements for gates, gates are not interchangeable if a jet bridge is down. In the event gate

78 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports equipment is out of service, the airlines have to adjust operations as needed within their own gates. For this reason, it is crucial for maintenance to have sufficient staff, budget, and spare parts to maintain systems and complete repairs to quickly return to normal operations. The airport has a CMMS that tracks all repairs, services, equipment, and components, includ- ing historical data for a 5-year time period. The CMMS also provides information about equip- ment age, which can be used to determine when and which components need to be replaced. Maintenance and technician history is held in the CMMS, and equipment audits can be obtained. To return equipment to service as soon as possible, the airport stocks spare PCA, ground power units, and key parts—such as preprogrammed motherboards—to repair or replace out-of-service equip- ment as quickly as possible. ABM monitors manufacturers’ warranties of PCA and ground power spare parts to compare the cost effectiveness of using new versus reconditioned parts. Another maintenance best practice includes checking aircraft 400 Hz receptacle functionality and alerting the airline if a problem is found. Finally, a five-person overnight crew handles most significant jet bridge maintenance to ensure that these systems are available at the start of the next operational day. The airport does not use hardstands for passenger loading, but there are many remain- overnight parking positions in use for airlines that pre-stage their aircraft for early morning flights. Airlines service remotely parked aircraft with mobile, diesel-powered PCA and GPUs, as remain-overnight positions are not equipped with electric PCA or ground power. The mobile units are also used if gate electrification equipment is out of service. The airport stresses that frequent communication between parties is key to smooth operations. They hold a full maintenance crew weekly meeting to discuss all ongoing repairs and strat- egize priorities for the week ahead. Based on demand and needs, the meetings may include site-specific safety training, corporate safety training, or other trainings to enhance knowledge of the equipment. Often, the maintenance contractor will work with airline ground crew staff to provide training on equipment operations to reduce maintenance costs and ensure that systems run efficiently. All parties share the same goal of customer satisfaction, so they work to enhance communications between all parties and bring people together to achieve this goal. This effort has been effective in ensuring a well-trained ground crew. Drivers for Installation • Build stakeholder relations, and be a good neighbor. • Demonstrate industry leadership and environmental proactivity. Finance Strategy • Gates were equipped with gate electrification equipment as part of a prior terminal renovation project. • Jet bridges and gate electrification equipment is replaced as needed, and the oldest are currently approximately 16 years old. • The jet bridge replacement program is included in the airport’s capital program budget. • The airport is not eligible for VALE funding. • Gates are leased to airlines on an exclusive basis (airlines do not share gates). And electricity costs are built into lease terms (gates are not individually metered, but airlines are charged by square footage and number of jet bridges). Planning and Policy • An informal communications system between airport operations, maintenance staff, and the airlines is in place. Maintenance meets with airline station managers every few weeks to

Airport Case Studies 79 discuss concerns or problems. If a problem arises, airlines call a duty phone, and a response is provided within 15 minutes. • Airport maintenance communicates with pilots, encouraging PCA use instead of APUs even during hot weather. Tracking and Data Collection on Utilization • PCA and ground power equipment have hour meters that track time in use, but the meters are not tied into the airport’s CMMS, and data must be retrieved manually. • Anecdotal observations from airport and maintenance staff show that airlines nearly always plug into equipment when available unless they have a very quick turn time. • Maintenance staff record run-time data during quarterly preventative maintenance checks but do not track utilization of the equipment in any other manner. • Airlines track APU usage per aircraft but do not regularly maintain records of which gates a particular aircraft has used. Airline station managers generally track fuel use per day by APUs in aggregate. Lessons Learned and Best Practices • Maintenance staff keep critical system spare parts on hand to ensure a quick return to service. • A five-person overnight maintenance crew ensures that heavy maintenance and preventative maintenance do not occur during the operational day, whenever possible. • The airport employs a dedicated maintenance team to service all gate electrification systems to ensure consistency and reliability. Figure 26. Clockwise from top left: 400 Hz ground power unit, aircraft connected to the PCA unit, 30-ton PCA unit, and aircraft connected to the 400 Hz ground power unit (Source: Jerome Cowart, ABM).

80 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports • Focus on training staff to prevent equipment misuse and to ensure that PCA and ground power units are shut down properly by ground crew, reiterating that it is crucial to use proper shut-down procedures and only use the emergency shut-down button in the event of a fire or a real emergency. – In general, the airport has observed that airline-employed, in-house ground crews are more reliable than contracted third-party ground crews. • Safeguards employed for reducing equipment wear and tear include the following: – Pre-position hoses and cables. – Purchase power cable heads that are sturdy and designed to withstand being run over by aircraft once or twice without being damaged (cables currently supplied by JBM Aviation). – Use clips to prevent PCA hose from laying on the ground. – Utilize safety switches on jet bridges that prevent them from moving until the power cable is properly connected or stored. • Airport maintenance staff report that the most common cause of ground power malfunction is damaged cable head pins, which prevent connection. There may also be damage on the aircraft receptor for ground power cable. Aircraft receptors can be tested with a hand-held gauge to determine if there is damage that would prevent a connection. 6.7 Memphis International Airport (MEM), Memphis, Tennessee Background Memphis International Airport is undergoing a concourse modernization project through 2021 to allow for consolidation of airline operations, retail, and general updates to the facility, which are all to be located in a redeveloped Concourse B (Figures 27 and 27A). Currently, airlines are operating out of gates in Concourses A and C. After the project is complete, all airlines will operate out of the 23 new gates in Concourse B, providing equiva- lent function, more flexibility in gate allocation, and no future incremental costs associated with equipping gates with gate electrification equipment, since this is a component of the modernization project. Currently, maintenance of the gate electrification systems is handled by a mix of airport staff, airline staff, and third-party service providers. Airport-owned gate equipment is maintained by staff. Airlines generally provide operations and maintenance on their own gate equipment using airline staff and third-party support. Some critical parts, including compressors, are available on site, but there is not a large inventory of spare parts maintained on site. Parts are ordered and shipped as needed, which can cause delays in repairing systems. Maintenance communications include regular meetings between the airport and airlines to systematically discuss issues. Training is provided for ground service handlers, but due to high turnover training is not as effective in molding behavior. Communication between airport and airlines is key to efficiently report, respond to, and resolve equipment outages. Airport staff collaborates with airline station managers and ramp staff. Regular maintenance staff are not available after hours or on weekends, which can present a challenge to utilization if repairs are needed during these times. Outside of normal working hours, the airlines contact airport dispatch to radio after-hours staff. One major challenge for Memphis International is ensuring that the electric PCA is utilized during hot weather periods over the summer months. To combat the heat, the airport has upsized all PCA units from 30 tons to 50 tons. If it is too hot onboard the aircraft, some pilots will keep APUs running. The airport does not collect information from airlines with regard to

Airport Case Studies 81 Figure 27. Aerial view of Memphis International Airport. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 3A, Warm/Humid Large hub, primary, commercial, military • Passengers: 4,196,259 • Passenger growth: 4.88% • Cargo weight: 9,562,537,748 lbs. • Cargo growth: 0.34% 2017 data provided by the airport. • There are 26 operational gates. Terminal B is currently closed for construction. • 11 gates equipped with electric PCA, owned by the airport • 11 gates equipped with electric GPU, owned by the airport • All PCA units are portable, and three mobile units are diesel powered. No central units are in service. • VALE-funded units are tracked by hour meters to calculate emissions reductions. • No electrical meters are on equipment, and systemwide utilization rates are not tracked. Major Tenants Regulatory Issues • Passenger airlines: American Airlines, Allegiant Air, Delta Air Lines, Frontier, Southwest Airlines, and United Airlines • Cargo: FedEx and UPS • VALE status: Eligible • Current NAAQS status: Maintenance zone for CO and ozone (8-hour) nonattainment areas (lead nonattainment or maintenance not confirmed) • VALE participation: $2,446,731 for 11 GPUs and 11 PCA for 11 gates (FY 2016) Figure 27A. Memphis International Airport specifications. APU use, and protocols vary by airline. One airline has a best practice to turn off the APU at every turnaround. Another challenge is related to how hoses are stored and used. The effectiveness of hoses are decreased when ground handlers do not remove kinks. Airport staff have observed that hose equip- ment needs may also vary by plane size. Longer hoses are needed for larger planes but, in other cases, the length is not necessary. To address this challenge, one airline has implemented a rack system to keep hoses off the ground, minimize wear, and provide predictable hose length. Another option is retractable hose equipment that enables the hose to stay off the pavement and prevent heat transfer. The convenience of rack systems and retractable hose use will still vary based on aircraft type.

82 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Drivers for Installation • Ongoing modernization project will move all gates to Concourse B, where they will all be equipped with gate electrification systems. • Both airport and airlines consider installation of gate electrification systems a sound business decision, enabling them to meet shared business goals. • No state or local regulatory pressure currently exists. Finance Strategy • New gates will be included as a component of the Memphis International Airport Modernization project. • The airport plans to apply for another VALE grant to support additional gates. Planning and Policy • No formal airport policy exists that requires airline use of electric PCA and ground power. • Airlines train their own ramp staff annually on equipment use. • Airlines have preventative maintenance programs to maintain equipment in a standardized manner. Tracking and Data Collection on Utilization • Equipment purchased with VALE grants is equipped with hour meters to track use for estimating emissions reductions. However, the airport does not formally track PCA and ground power utilization as a percentage of time the equipment is in use when available. • Gates are only metered with hour meters; not with electrical meters. Therefore, electricity use of the equipment is not tracked on a gate-by-gate basis. • The airport must log hours of run time for the VALE-funded units, as per grant requirements. • Airlines use some hardstand operations while the airport is undergoing construction. Hard- stands are serviced by mobile, diesel-powered PCA and GPUs, or aircraft run the APUs. Lessons Learned and Best Practices • Three airlines provided written assurances in the airport’s VALE grant application that they intend to use the VALE-funded electric PCA and ground power equipment. • Maintaining aging equipment and availability of spare parts presents maintenance issues, causing delays in bringing equipment back in service. • Communication with equipment manufacturers with regard to maintenance needs and pre- planning is important. • Airport and airlines identified a need for additional training for equipment users on the proper operation of the equipment to prevent damage. 6.8 Phoenix Sky Harbor International Airport (PHX), Phoenix, Arizona Background The City of Phoenix owns and operates Phoenix Sky Harbor International Airport (Figure 28). Due to the extremely hot and dry climate, electric PCA and 400 Hz ground power have historically been important components of the airport’s infrastructure to support operations

Airport Case Studies 83 Figure 28. Phoenix Sky Harbor International Airport. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 2B, Hot/Dry Large hub, primary, commercial • Passengers: 43,921,670 • Passenger growth: 1.20% • Cargo weight: 375,260 tons • Cargo growth: 5.70% • Number of airlines serving: 16 2017 data provided by the airport. • There are 97 operational gates, with a mix of owned by the city (airport) and owned by airline. • All 97 gates equipped with 400 Hz ground power. • All 37 city-owned gates are equipped with electric PCA. Most, but not all, airline-owned gates have electric PCA. • Combination of central system and point of use • One central system is owned by the airport, which serves six gates. And three central systems are owned by American Airlines. • Four regional jet hardstands • Electric ground power at multiple FedEx cargo stands • Utilization rate not systematically tracked Major Tenants Regulatory Issues • Passenger airlines: American Airlines, Southwest Airlines, Delta Air Lines, and United Airlines • Cargo: UPS, FedEx, Air Transport International, and DHS–Atlas Air Passenger and cargo carriers with greatest market share listed • VALE status: Eligible • Current NAAQS status: Maintenance zone for CO, Moderate for ozone (8-hour), and Serious for PM10. • VALE participation: Grant received in FY 2015 for electric ground support equipment charging stations but not for gate electrification equipment Figure 28A. Phoenix Sky Harbor International Airport specifications. and to ensure customer safety and comfort. The gates are a mix of city owned (airport) and air- line owned (Figure 28A). All 97 gates have 400 Hz ground power, all 37 city-owned gates are equipped with electric PCA, and the majority of the 60 airline-owned gates have electric PCA. The PCA systems are designed and sized appropriately to handle the extreme Arizona heat and can effectively cool aircraft cabins to comfortable conditions even when ambient tempera- tures are up to 120°F. The jet bridges have two air-handling units: one to cool the aircraft and one to cool the jet bridge. Otherwise, jet bridges will have a separate air-conditioning unit on the roof. Conditioning the jet bridges helps to keep passengers comfortable during the loading and unloading process and prevents the jet bridge from drawing cool air from the aircraft cabin when the door is open. Maintenance responsibilities are shared by the airport and airlines. Some airlines have inter- nal maintenance staff and others have contracted staff. Airport maintenance staff maintain a small inventory of spare parts and three portable units for both PCA and ground power in case

84 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports gate equipment is down for an extended period or if there are emergency landings. When main- tenance issues arise with the central plant systems, the repair of these systems takes priority since they serve multiple gates. The airport has a maintenance plan, which includes replacing equip- ment 2 to 3 years ahead of standard expected useful life, depending on reliability of equipment. This plan helps to maximize system availability. Drivers for Installation • Equipment was originally installed in the late 1990s to address airlines’ needs, passenger comfort, and air quality issues. • International concourse central PCA system was installed, since aircraft APUs do not suffice during the hottest months. Finance Strategy • Airline paid for acquisition and installation of equipment on their gates through capital programs budget (no VALE grant funding). • Airlines funded the development of central plant and for equipment on the gates they own. • Airlines are charged for electricity use based on their gate lease terms. Planning and Policy • The airport facilitates coordination and collaboration with airlines concerning airline and airport facility needs. • There are no requirements or guidelines from the airport to airlines that dictate use of gate electrification equipment. Tracking and Data Collection on Utilization • Utilization of electric PCA and 400 Hz ground power is not tracked. • The centralized plant on the international concourse has an electrical meter. • The city is not permitted to charge airlines directly for electricity, so fees are included in rates and charges. Lessons Learned and Best Practices • Although the airport does not formally track utilization, airport staff note that utilization rates are high as airlines want to save fuel and keep passengers comfortable (weather can get too hot in Phoenix for APUs to effectively cool aircraft cabins). • Preventative maintenance plan—The airport has 5- and 10-year maintenance plans: – For standard expected useful life of equipment, the airport aims to be ahead of standard by 2 to 3 years, depending on reliability (i.e., not waiting until equipment is at the very end of useful life to replace). • Situations that result in airlines using APUs (anecdotal observation from airport staff) include: – Quick turnarounds; – Operator error, particularly with regard to the order of connecting power cables to aircraft where two are needed; – Operator error in system start-up and shut down; and – Older aircraft can sometimes trip the ground power equipment. • Established procedural systems to track and manage maintenance of electric PCA and ground power equipment help minimize time out of service.

Airport Case Studies 85 6.9 Pittsburgh International Airport (PIT), Pittsburgh, Pennsylvania Background The existing terminal building at Pittsburgh International Airport opened in 1992 (Figure 29). It is equipped with electric PCA and 400 Hz ground power on 68 jet bridges (Figure 29A). The decision was driven in large part by US Airways’ desire for gate electrification due to the airline’s presence as the dominant carrier at Pittsburgh International during that time. Figure 29. Pittsburgh International Airport aerial view. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 5A, Cool/Humid Medium hub, small, primary, commercial, reliever, military • Passengers: 8,988,016 • Passenger growth: 8.2% • Operations growth: 5% • Cargo weight: 148,342,856 (lbs.) • Cargo growth: -1.30% • Number of airlines serving: 14 2017 data provided by the airport. • There are 76 operational gates, 68 with jet bridges. • All 68 jet bridges are equipped with electric PCA and 400 Hz ground power. • Six exclusive-use gates are equipped with electric 28 VDC ground power, acquired by the airline and installed and maintained by the airport. • PCA is provided by a central system along with auxiliary heater units. • All gates are airport owned and leased to airlines on both an exclusive-use and common-use basis. • Airlines use mobile PCA and GPUs to service aircraft at gates without electric PCA or 400 Hz ground power. Major Tenants Regulatory Issues • Passenger airlines: Southwest Airlines, American Airlines, Delta Air Lines, United Airlines, JetBlue Airlines, and Allegiant • Cargo: FedEx, UPS, and Qatar Airways Cargo Passenger and cargo carriers listed by greatest market share • VALE status: Eligible but has not participated • Current NAAQS status: Maintenance zone for CO and PM2.5 and Marginal ozone (8-hour) Figure 29A. Pittsburgh International Airport specifications.

86 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports The airport recently announced plans to modernize the terminal, updating how the airport looks and operates. The modernization project includes updates to both the gates and jet bridges. The airport owns and maintains the electric PCA and ground power systems, leasing gates to airlines on either an exclusive-use or a common-use basis. In light of the impending upgrades, airport staff are tasked with maintaining the functionality of existing systems and equipment until the modernization plan is complete. The airport has a unique central air-chilling system for the PCA, which is designed to provide comfortable conditions in any season. This central plant opened in 1992, along with the terminal building. The system as a whole is now 25 years old (though individual components have been replaced), and maintenance presents an ongoing challenge. The central chiller system provides air to the PCA units and has a unique design in which water is used for cooling in conjunction with electricity; there are no outside cooling towers. There are two separate systems that allow for summer cooling and winter heating with the assistance of auxiliary heater units. Therefore, determining the system switch-over date presents a challenge. The PCA temperature can be adjusted somewhat, depending on weather conditions, but this often presents challenges during months when daily temperatures fluctuate (fall and spring). Operational costs for electric PCA and ground power are paid by the carriers through direct charges or as built-into leases. Airlines with exclusive-use gates are charged for electricity con- sumption per gate (tracked through electrical meters at the gates). These data are gathered auto- matically and billed to the airlines each month. Tenants at common-use gates are billed a set fee, which includes electricity costs but is not based on actual usage. This arrangement is referred to as a “per-turn fee” for common use gates. The airport maintains all gate electrification equipment and upholds a high level of system availability, despite the challenge of aging equipment. The airport has a number of best practices in place to maximize system availability. These include dedicated maintenance personnel for the jet bridges and gate electrification equipment; 24-hour coverage of maintenance staff; and regu- lar communications about operational status of equipment between airport operations staff, maintenance staff, and airline staff. When problems arise, the airport works with the airlines to identify and resolve the problem. For example, in winter 2017–2018, the air temperature from the PCA equipment at one gate was too warm, prompting pilots using that gate to routinely dis- connect from the PCA and utilize APUs to maintain a comfortable cabin temperature. Airport maintenance staff investigated the source of the problem and determined it to be caused by a faulty valve, which was consequently fixed. Drivers for Installation • Acquisition and installation of the original equipment was driven by airline interest. At the time, Pittsburgh International was a hub for US Airways. • The airport did not identify any regulatory drivers for the installation of gate electrification equipment. • The airport has a number of environmental initiatives and goals, but there has not been any specific community pressure concerning air quality. Finance Strategy • Installation was initially financed in 1992 as part of the capital project for the existing terminal. • Upgrades to the gates and jet bridges are planned for the current modernization project and will be financed as part of that capital project. • The airport has not utilized VALE funding in the past, but it may consider it in the future.

Airport Case Studies 87 Planning and Policy • Original installation was driven by US Airways, but all airlines are supportive. The airport is working in collaboration with airlines on system and equipment needs for the modernization project. • The airport routinely reviews a 3-year maintenance history to gauge system needs and to appropriately plan for system operations and maintenance budget. • Repair costs are absorbed by the airport, but there are mechanisms in place for charging carriers and operators if damage to equipment occurs from negligence or extreme circumstances. • The airport’s vice president of Terminal Operations works with air carriers concerning large or recurring issues to collaborate on solutions. Tracking and Data Collection on Utilization • The airport does not track PCA and ground power utilization, but anecdotal observations pro- vide evidence that utilization rates are very high where equipment is available and operable. • Electricity consumption is tracked at gates with individual meters, and airlines are conse- quently billed for their use. • The airport tracks complaints concerning when equipment is out of service or in need of maintenance. Lessons Learned and Best Practices • Airport staff observe that the following conditions result in aircraft using APUs: – Ground crew misuse of equipment, – PCA hose kinks and damaged power cable heads and pins, – High ambient temperatures render PCA ineffective (though the air temperature of PCA can be adjusted), – Other weather hazards prevent ground crew from connecting aircraft, and – Worn PCA valves prevent PCA system from effectively conditioning aircraft. • Maintenance best practices include: – Constant real-time communication between airport operations, maintenance staff, and airline staff in the event of equipment outage to enable quick repairs and notification when equipment is back in service; – Employ round-the-clock maintenance staff, including electricians, and a dedicated jet bridge maintenance crew to minimize repair time due to staff expertise; – Maintain comprehensive maintenance records to enable staff to identify issues that result from misuse of the gate electrification equipment in comparison to equipment failure (e.g., due to age); – Maintain an on-site spare parts inventory to decrease maintenance delays as a result of ordering equipment from off-site manufacturers; and – Preserve additional gate capacity to provide some flexibility if a jet bridge goes out of service. 6.10 Portland International Airport (PDX), Portland, Oregon Background Portland International Airport (Figure 30) is focused on enhancing the quality of life for the communities it serves and, as stated in the Port of Portland Environmental Report 2016/17 (2017), “integrat[ing] environmental stewardship into our daily operations.” Portland International has

88 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports a number of environmental goals, including minimizing the impact of operations on air quality. In addition, Portland International community stakeholders are active, engaged on environ- mental initiatives, and broadly concerned with air toxics in their local environments. The instal- lation of electric PCA and 400 Hz ground power units contributes to meeting the airport’s air quality and greenhouse gas emissions reduction goals. In 2016, the airport was awarded a $5.7 million VALE grant from FAA, enabling the purchase and installation of 26 electric PCA units (Figure 30A). Use of the newly installed equipment—in combination with electric GPU use—is expected to result in substantial emissions reductions at the airport. Over 13 years, Portland International estimates that the units will “reduce fuel Figure 30. Portland International Airport aerial view. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 4C Mixed/Marine Large hub, primary, commercial • Passengers: 19,080,494 • Passenger growth: 4.0% • Cargo weight: 246,917 tons • Cargo growth: 6.8% • Number of airlines serving: 16 2017 data provided by the airport. • There are 53 operational gates: 42 gates have jet bridges, and 12 have hardstand gates. • 41 of the passenger boarding bridges are equipped with electric PCA (31 are airport owned, and nine are airline owned), all point of use. • 45 gates are equipped with electric GPUs that are owned by the airport. • Hardstands and unequipped passenger boarding bridge gates are served by airline-owned, mobile, diesel-powered PCA and ground power units. • VALE-funded equipment use is tracked to estimate emissions reductions, but utilization rates are not systematically tracked. Major Tenants Regulatory Issues • Passenger airlines: Alaska, Southwest Airlines, United Airlines, Delta Air Lines, Horizon Air, and American Airlines • Cargo: FedEx and UPS Passenger and cargo carriers with greatest market share listed • VALE status: Eligible • NAAQS status: Formerly maintenance area for CO. In attainment for all. • VALE participation: FY 2016: $5,700,600 for 26 PCA units for 26 gates Figure 30A. Portland International Airport specifications.

Airport Case Studies 89 consumption by approximately 6 million gallons, carbon monoxide emissions by 122 tons, and carbon dioxide by 62,000 tons” (Port of Portland 2017). The remaining 15 passenger boarding bridges have electric PCA and 400 Hz ground power units that were purchased and installed by the airport. To maintain VALE grant compliance, the airport tracks hours of use, as well as energy use data for the VALE-funded PCA units. This information is collected quarterly. The airport plans to install hour meters on the remaining PCA units (i.e., those that were not funded with VALE grants) in the future to account for energy use and factor it into their greenhouse gas inventories. The airport also foresees investing in upgrades to the remaining passenger boarding bridges in the future, with a plan to invest in units that have electric PCA, 400 Hz ground power, and indi- vidual metering as standard components. The ownership structure of the gates is mixed. The airport owns 31 of the passenger boarding bridge gates, and airlines own nine. The gates are leased to the airlines, with some common use and others exclusive use. The maintenance of the electric PCA and ground power units are handled by in-house airport maintenance staff and managed through a maintenance operations center. The ground handling crew for airlines includes both air- line staff and contracted employees. Maintenance requests or issues are handled through informal communication between airport staff and carrier staff. PCA units receive quar- terly maintenance while GPUs receive both quarterly and annual comprehensive preventa- tive maintenance procedures. In addition, Portland International maintains round-the-clock maintenance coverage for the 400 Hz ground power units. Finally, airport maintenance staff have a spare parts inventory to facilitate quick repairs as needed, though the Port’s ability to maintain a comprehensive spare parts inventory is a challenge because of lack of equipment standardization. Drivers for Installation • Air quality regulatory considerations are currently in attainment for CO but were previously in maintenance. • VALE grant and airline support are available. • Airlines have historically pursued installation of electric PCA and ground power, in part, due to lower fuel costs and, in part, motivated by decreased maintenance costs associated with APU use. • The Port of Portland has a 14001-certified Environmental Management System under which objectives and targets are established, including a target to assist airlines in meet- ing their industry environmental and carbon reduction goals. Electric PCA greatly reduces aircraft greenhouse gases, criteria pollutants, and air toxics, as well as reduces fuel consumption. Finance Strategy • Capital comes from airport, airlines, and external funding. • The FAA VALE grant was leveraged for funding 26 point-of-use systems in 2016. Planning and Policy • Stakeholders involved in the planning and acquisition of electric PCA include many airport departments, such as finance, operations, maintenance, and engineering. • The jet bridge replacement plan includes investment in bridges that have electric PCA and 400 Hz ground power, as well as individual meters as standard components on the new equipment.

90 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports • An Operational and Maintenance Plan is in place. • Preventative maintenance includes quarterly maintenance and annual maintenance of the units. • Airline policies improve utilization. Tracking and Data Collection on Utilization • The airport tracks hours of use and energy use information for equipment purchased with VALE grants as part of grant compliance. • The airport does not track utilization of units not funded with VALE grants, though it plans to do so in the future. • Due to the cost and complexity associated with metering, Portland International plans to utilize a single meter on future jet bridges to save costs associated with additional submeter- ing of components. Lessons Learned and Best Practices • Standardization of PCA and ground power equipment and units is key for decreasing main- tenance labor and cost. This results in: – Reduced training complexity and – Spare part compatibility. • Retrofitting jet bridges leads to greater complexity and cost than purchasing jet bridges already outfitted with PCA, GPU, and metering. • The airport would like to have equipment capable of automatically uploading information from PCA and ground power into its CMMS. • Anecdotal observations by airport staff identify the following reasons for non-use of electric PCA and/or ground power: – Operator error in connecting the power cable or PCA hose kinks; – Operator failure to properly turn on equipment; and – Operator damage to power cable pins, power cables, or PCA hoses (i.e., not stored properly or being run over by ground service equipment vehicles). • Insufficient training for ground crew inhibits utilization, which may be affected by high turnover of ground crew. 6.11 Sacramento International Airport (SMF), Sacramento, California Background Sacramento International Airport was one of the first airports in the U.S. with 100 percent of jet bridges equipped with electric PCA and 400 Hz ground power units (Figure 31). The airport is located in a valley with poor air quality, providing a strong incentive for measures to reduce air pollutant emissions. Sacramento County and the other surrounding counties do not meet EPA NAAQS for 8-hour ozone or PM 2.5. The airport owns and maintains all of the equipment and funded the acquisition, installation, operation, and maintenance of all PCA and ground power equip- ment (Figure 31A). It has a rigorous maintenance program that results in very minimal down time, which has resulted in a high system utilization rate (i.e., >95%, exclusive of regional jets), according to a study conducted in 2011 (B. Taylor, personal communication, Nov. 18, 2011). The biggest challenge to the use of these systems (or conversely, a reduction in the use of APUs at the gates) is related to weather. When ambient temperatures are above 100°F, the PCA

Airport Case Studies 91 Figure 31. Sacramento International Airport aerial. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 3B, Warm/Dry Medium hub, primary, commercial • Passengers: 10,912,080 • Passenger growth: 7.8% • Cargo weight: 148,885,057 lbs. • Cargo growth: 7.2% • Number of airlines serving: 17 2017 data provided by the airport. • The airport has 31 operational gates, all equipped with electric PCA and ground power. • Seven gates have both 400 Hz and 28 VDC. • Three gates have two 400 Hz ground power units to accommodate wide-body aircraft. • All gates are owned and maintained by the airport. • Diesel-powered mobile units are used for hardstand operations. • Utilization rate is not systematically tracked, but a limited study was completed in 2011 that showed high utilization (>95%) of gate electrification equipment. Major Tenants Regulatory Issues • Passenger airlines: AeroMexico, Alaska, American Airlines, Delta Air Lines, Horizon, JetBlue Airlines, Southwest Airlines, Skywest/Compass, and United Airlines • Cargo: FedEx and U.S. Postal Service Express Mail • VALE status: Eligible, though VALE grants are not used. • Current NAAQS status: Moderate zone for PM2.5 and Severe zone for ozone (8-hour) Figure 31A. Sacramento International Airport specifications. equipment has difficulty cooling the aircraft, and pilots tend to leave APUs running. Although both the airport and airlines feel that the equipment is right-sized, there may be opportunities to address the heat-related challenges with some component modifications that keep PCA hoses off the hot pavement, for example. Drivers for Installation • Poor regional air quality was the primary motivation for the airport to install gate electrification equipment.

92 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports • The secondary motivation was to provide attractive service to air carriers due to understood fuel and maintenance cost of running the APU. • An unforeseen co-benefit has been reduced congestion of the ramp area, resulting in more efficient and safer ground operations. Finance Strategy • Equipment installed on the original Terminal B jet bridges was funded with the operating budget. • All Terminal A and new Terminal B equipment was funded with the Capital project budget. Terminal A opened in 1998, and the new Terminal B opened in 2011. • The airport leadership was committed to installing PCA and ground power equipment at each gate because of regional air quality concerns. – The airport is eligible for VALE grants but has not utilized federal grants for the acquisition or installation of the equipment. – Airlines are not charged directly for electricity; it is included in rates and charges. • Airlines have their own internal cost calculations and have found that there is a benefit to using PCA and ground power instead of APUs. Operation, Maintenance, and Training • Airport staff maintains the equipment, and jet bridges (including PCA systems) are given priority, especially during summer months. • Both corrective and preventative maintenance are performed on system components to mini- mize down time. • Some airlines have in-house ground crews and conduct their own training on gate electrification equipment use. Other airlines use a third-party ground handling company, primarily GAT Airline Ground Support, Inc. Planning and Policy • Monthly station managers meetings are conducted so that airport staff and airlines can coordinate on issues, including those related to gate electrification equipment. • Airport maintenance staff regularly communicate with airline and ground crews on the status of equipment when there is a maintenance issue. • There is no airport requirement for airlines to use equipment, but all airlines reported having corporate policies to this effect. – Other related policies include airlines requesting passengers to lower window shades or precooling aircraft before arriving at gate. Tracking and Data Collection on Utilization • Airport conducted a survey of PCA and 400 Hz ground power use by airlines in 2011. This involved staff observing airline operations over 24 hours. • The airport found a utilization rate of ground crew connecting aircraft to gate electrification equipment of greater than 95 percent (less than 5 percent of the time the aircraft were not connected to equipment). • One airline representative reported monitoring daily APU fuel burn via a dashboard to reduce costs. • Both the airport and airlines reported the most significant challenge to utilization of PCA is hot weather. PCA equipment cannot effectively cool aircraft when temperatures get extremely hot.

Airport Case Studies 93 Lessons Learned and Best Practices • When ambient temperatures are above 100°F to 105°F, the PCA has difficulty cooling aircraft. • Pavement heat transfers to hoses, even with insulation. PCA air temperature increases over 30°F to 40°F from the time it leaves the PCA unit to the time it gets to aircraft. The airline sees the problem but cannot alter equipment—such as attach the PCA hose to the bridge— because it is owned by the airport. • Short turns of 24 minutes or less are not possible to cool down the cabin with PCA. • Terminal A gates are submetered. However, these data are not tracked or used. Terminal B gate meters include all electricity use and cannot break out PCA and ground power use. • Data are currently not available for calculating the cost benefit of highly utilized gate equipment. • 28 volt cables are not being used because the cables are not long enough to reach where the aircraft (i.e., DH8s) park. • Several factors seem to influence the high utilization rate at Sacramento International: – Universal equipment availability, – Reliable and prompt maintenance (and the airport’s reputation with air carriers for having available, working equipment), – Good two-way communication between airport staff and airlines on the status of equip- ment through daily communication and weekly station manager meetings, – Airport ownership and control of all equipment, – Right-sized equipment for fleet, and – Strong motivation with regards to poor regional air quality. 6.12 San Diego International Airport (SAN), San Diego, California Background The San Diego International Airport, owned and operated by the San Diego County Regional Airport Authority, is a large hub airport located in Southern California, which has both current and historical air quality challenges (Figure 32). Because of these challenges, the airport has aggressive air quality and environmental goals and has voluntarily developed an air quality management plan and entered into a memorandum of understanding (MOU) with the Attorney General for the State of California in 2008 for the reduction of greenhouse gases. One measure specifically listed in both the MOU and the air quality management plan is the installation of electric PCA and 400 Hz ground power on all new or refurbished gates. Now, all gates are equipped with both electric PCA and 400 Hz ground power (Figure 32A). The airport has installed the equipment in multiple phases and, as a result, not all of the equip- ment is the same on each gate. The reliability of the equipment is high and is well maintained by the third-party contractor (Siemens), but the inconsistency in equipment and meter type makes data collection challenging. The equipment-use information must be collected manually and does not automatically upload into the airport’s automated information management and monitoring system (AIMMS). The airport tracks use of PCA and ground power equipment, as required by VALE (hours of use), and has undertaken informal observational studies, which demonstrate anecdotally that utilization is high and aircraft are plugging in quickly upon arrival at the gate. As the mainte- nance provider, Siemens also tracks usage of equipment but does not systematically report it or provide the data to the airport unless asked. The airport has attempted to track utilization of gate electrification equipment in a more detailed, systematic manner, but it does not currently have a

94 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 32. Aerial view of San Diego International Airport (Source: San Diego International Airport). Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 3B, Warm/Dry Large hub, primary, commercial • Passengers: 22,173,493 • Passenger growth: 7.00% • Cargo weight: 166,135.2 (tons) • Cargo growth: -1.30% • Number of airlines serving: 17 2017 data provided by the airport. • There are 51 operational gates, with 40 owned by the airport and 11 owned by the airline (mixed ownership structure). • All gates are equipped with electric PCA and 400 Hz ground power and all point-of-use systems. • Hardstands are used for overnight parking only. • 56 diesel-powered mobile PCA and GPU units service the aircraft when gate electrification equipment is out, at hardstands, or for business aviation jets (airline and fixed-base operator owned). • Utilization rate is tracked through hour meters and through electric meters on some gates. Major Tenants Regulatory Issues • Passenger airlines: American Airlines, Alaska, Delta Air Lines, Southwest Airlines, and United Airlines • Cargo: DHL Express, FedEx, and UPS Passenger and cargo carriers with greatest market share listed • VALE status: Eligible • Air quality status: Federal nonattainment (moderate) for ozone 8-hour and state nonattainment for ozone 8-hour, ozone 1-hour, PM 2.5, and PM 10 • VALE participation: FY 2013 grant for PCA at 18 existing gates, FY 2011 grant for PCA at 10 existing gates, and PCA and ground power at 10 new gates as part of terminal expansion project Figure 32A. San Diego International Airport specifications. satisfactory method of obtaining airline daily schedule information or APU-use information. The airport is exploring using gate utilization software programs to obtain more granular insights into the types of aircraft using each gate and the duration at each gate. Drivers for Installation • The airport’s MOU with the California Attorney General is designed to reduce greenhouse gases. • Airlines support fuel savings, efficiency, and safety. • Availability of grants was less of a driver but helpful.

Airport Case Studies 95 Finance Strategy • Southwest Airlines purchased their own PCA and ground power equipment for their 11 gates. • The airport funded the electrification of their 40 airport-owned gates through the capital projects budget as part of the modernization project and received VALE grants for the remaining gates in FY 2011 and FY 2013. Planning and Policy • Some airlines report that plugging into PCA and ground power is one of the first items on their operations checklist (Figure 33). • While use of PCA and 400 Hz ground power is not required by the airport, the MOU language is included in the lease agreements to encourage use. • The airport conducted early coordination with airlines during the VALE application process to ensure their support. Tracking and Data Collection on Utilization • Electricity is included in airlines’ rates and charges. Airlines are not charged directly based on electricity use, even though some jet bridges are individually metered. • Some individual jet bridges are metered. However, since the gate electrification equipment was purchased in two phases, the equipment and meters are not consistent. The information from the meters can be challenging to gather and, historically, has not integrated automatically into the AIMMS. But the San Diego County Regional Airport Authority has initiated a project to better incorporate jet bridge data into AIMMS. • The airport has conducted informal utilization observations and reports high rates of utiliza- tion with quick connection times. However, the observational study did not evaluate whether aircraft APUs were still running. Lessons Learned and Best Practices • The airport is currently integrating all metering data into the AIMMS. • The airport is in the process of procuring gate utilization software to get more granular insight into types of aircraft and duration at gates. It expects the software to be fully operational in 2019. Figure 33. PCA and GPU connection at SAN jet bridge (Source: San Diego International Airport).

96 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports 6.13 Seattle–Tacoma International Airport (SEA), Seattle, Washington Background The Seattle–Tacoma International Airport (Figure 34) is one of the fastest-growing airports in the U.S., with more than 43 percent growth in passenger traffic since 2012 (Nordstrom 2018). As such, the airport is undergoing expansion and construction. All gates with jet bridges have electric PCA and 400 Hz ground power; the exact number varies depending on construction, but there are currently approximately 70 jet bridges (Figure 34A). The gates and PCA units started operation in a phased approach in 2013. The airport also has a hardstand terminal that serves six gates, which are not equipped with electric PCA or 400 Hz ground power. The airport has a unique centralized PCA system that was designed to accommodate 72 gates, with the capacity to accommodate up to 90 gates (Figure 35). The PCA system has a central chilled water plant and five central hot water plants (Figure 36). Seattle–Tacoma considers the PCA system as HVAC equipment and has integrated them into the airport’s building automa- tion system. The airport worked with the PCA equipment supplier through the procurement process to install Siemens’ compact controllers in each PCA unit. The controllers are com- patible with the airport’s building automation system, which enables direct communication between the PCA and the building automation system. The airport built graphics, informa- tion, and a programming interface into the building automation system to control the PCA systems. The building automation system allows the airport to monitor a variety of the PCA’s dimensions, including: • Notification when the Auto-lock/Auto-level is engaged on a jet bridge, indicating that an aircraft has arrived; • Whether the PCA fan blower is turned on; • The size of the aircraft based on the position of the variable frequency drive selector switch, which controls the speed of the fan to accommodate smaller and larger aircraft, as necessary; • Outside ambient temperature and temperature gauges to measure aircraft cabin temperature, which helps the airport determine what temperature the air in the PCA systems should be; • Temperature of air leaving the PCA through a PCA outlet temperature gauge to determine whether the cooling and heating settings are sufficient or to possibly indicate if there is a problem with the PCA hose; and • The chilled water valve and the hot water valve. The system does not provide information on whether the APU is running, since the APU is not connected to the system. In some cases, pilots will leave APUs running even when aircraft are connected to the PCA. It is not always known why, but some pilots have claimed that leaving APUs running when aircraft are connected to the PCA is to better circulate air on hot days. In addition to monitoring the variables listed above, Seattle–Tacoma tracks hours of PCA use, as per VALE grant requirements. Maintenance on the PCA and 400 Hz ground power systems is handled through Seattle– Tacoma’s operations center. The Operations Communication Center is monitored round the clock, 365 days a year, and handles all calls from airlines. The most common maintenance issues are the result of PCA hose mishandling and damage to the connectors. The mainte- nance team stocks extra hoses in case of equipment failure. In addition to equipment mis- handling, other causes for less-than-optimal utilization include the unwillingness of some carriers to connect to the PCA system. These carriers—particularly Asian carriers with short turn times—prefer to keep the APU running. Carriers that regularly use the hardstands also use APUs or mobile diesel units.

Airport Case Studies 97 Figure 34. Aerial view of Seattle–Tacoma International Airport. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 4C, Mixed/Marine Large hub, primary, commercial • Passengers: 46,934,619 • Passenger growth: 2.6% • Cargo weight: 425,856 metric tons • Cargo growth: 16.22% • Number of airlines serving: 34 2017 data provided by the airport. • There are 66 to 72 operational gates with jet bridges (fluctuation due to construction), and all gates are owned by the airport. • All jet bridges are equipped with electric PCA from one central cooling–heating plant and 400 Hz ground power. Additional natural gas–powered heating plants provide warm air, as well. • A hardstand terminal with six gates is not equipped with electric PCA and 400 Hz ground power. • There are a few portable PCA and diesel-powered GPU that are only used in emergency situations. Major Tenants Regulatory Issues • Passenger airlines: Alaska Airlines, Delta Air Lines, Southwest Airlines, and United Airlines • Cargo: ABX Air, Alaska Airlines, FedEx, and Air Transport International Passenger and cargo carriers with greatest market share listed • VALE status: Currently in attainment and not eligible. However, the airport was eligible in the past. • Current NAAQS status: Attainment • VALE participation: FY 2010 and FY 2011, $18.3 million and $3.6 million, respectively, to purchase PCA system. Figure 34A. Seattle–Tacoma International Airport specifications. Drivers for Installation • Protect air quality through a project expected to prevent emissions of 2,900 tons of nitrogen oxides throughout the equipment’s useful life (FAA 2017). • Reduce airport carbon footprint: The PCA system prevents 40,000 tons of CO2 emissions annually when fully utilized (Port of Seattle 2017). • Conserve fuel: The PCA system saves 5 million gallons of fuel each year (Port of Seattle 2017). • Enhance passenger comfort. • Foster community support and interest in Port of Seattle environmental management. • Decrease noise pollution from parked aircraft (Port of Seattle 2017).

98 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Finance Strategy • Leverage VALE grants. • The Port of Seattle conducted a cost–benefit analysis and determined that the PCA system saves $15 million annually in fuel costs for airlines, with a 2-year return on investment (Port of Seattle 2017). • Costs are included in rates and charges that the airport charges the airlines. Planning and Policy • The airport worked with the airlines to get support for VALE grant. • Some airlines have corporate policies to plug into PCA as soon as possible. These airlines track APU use and determine reasons for use. Tracking and Data Collection on Utilization • The building automation system monitors the PCA system and allows the airport to make adjustments for optimal performance (i.e., temperature of air, aircraft cabins, and when the PCA is on or off). Figure 35. Clockwise from top left: Ice storage in central plant, central plant pumps, kinked PCA hose, and aircraft connected to PCA and ground power (Source: Port of Seattle).

Figure 36. Central plant monitoring software display.

100 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports • Challenges related to aligning data from the building automation system with the actual time the aircraft remain at the gates and the inability to track APU use limits overall utilization calculations. • The SafeDock system exists at six gates, expanding use to additional gates to provide data on when airlines are at gates. Lessons Learned and Best Practices • Use of building automation system to monitor the PCA system is feasible because of the cen- tral system, and it allows the airport to better adjust the PCA to meet operating conditions and the needs of aircraft. • Operator error is the largest challenge inhibiting better utilization. Many issues stem from PCA hoses being improperly laid out and connected to the aircraft or pilots leaving APUs running on short turn times. • Consistent training is key. • The gates are able to accommodate various sizes of aircraft by varying the speed of the variable frequency drive on the fan motor, (i.e., adjusting the air flow rate to match the requirements of both narrow- and wide-body aircraft. Therefore, hoses must be long enough to accommodate both types of aircraft. While the variable frequency drive on the fan motor provides flexibility in use of the gates, it aggravates the issues with hoses noted above. 6.14 Tallahassee International Airport (TLH), Tallahassee, Florida Background Located in Florida’s capital city, the Tallahassee International Airport has a hot and humid climate, and properly conditioned aircraft cabins and jet bridges are essential at the airport. The airlines serving Tallahassee International strongly support the use of electric PCA and ground power to ensure passenger comfort and have backup diesel-powered mobile units to use when the PCA and ground power units are out of service. The airport has eight gates with jet bridges, and all are equipped with electric PCA (point-of-use units) and 400 Hz ground power (Figure 37). The equipment was originally installed around 2005. Reliability of the equipment is mixed, with equipment from certain manufacturers requiring more maintenance than other models. For example, vents on top of some of the ground power units let in water during precipitation events, which are frequent in North Florida, and the water causes the transformers to break. The airport is currently planning to replace all eight jet bridges, including the electric PCA and 400 Hz ground power equipment. This project will be funded through a state grant from the Florida Department of Transportation and passenger facility charges and will occur over several years. The airport is considering submetering for newly installed equipment. Maintenance of the systems is handled in house by Tallahassee International staff. The depart- ment has staff on site during normal business hours and on call during nighttime hours and on weekends. Airport maintenance staff use a tracking system to document historical replacement of spare parts and corrective actions taken to maintain systems. As a best practice, maintenance keeps a stock of spare parts on site as spare parts can take time to obtain. The maintenance budget is generally sufficient to handle the needed repairs; although, at times, the airport reports that staff are overloaded with work orders. The utilization of electric PCA and 400 Hz ground power is not tracked by the airport (Figure 37A). But staff observe that when gate electrification equipment is in service, the aircraft connect. (When gate electrification equipment is out of order, airlines use diesel-powered mobile units.)

Airport Case Studies 101 Figure 37. Aerial view of Tallahassee International Airport. Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 2A, Hot/Humid Non-hub, primary, commercial • Passengers: 732,235 • Passenger growth: 2.56% • Number of airlines serving: Three 2017 data provided by the airport. • There are eight operational gates with jet bridges, all owned by the airport. • All gates are equipped with electric PCA and 400 Hz ground power. • The airport owns one combination 28 V and 400 Hz ground power diesel-powered mobile unit; airlines own diesel-powered mobile units. • Utilization rate is not systematically tracked. Major Tenants Regulatory Issues • Passenger airlines: American Airlines, Delta Air Lines, and Silver Airways • Cargo: FedEx • VALE status: Not eligible • Current NAAQS status: Attainment Figure 37A. Tallahassee International Airport specifications. The airlines have a mix of in-house employees servicing aircraft and third-party contracted ground crews. Anecdotally, airport staff have observed that third-party contractors perform better than airline staff. Challenges to utilization include equipment mishandling by ground crews that results in the PCA or ground power equipment being out of service; for example, when PCA hoses or ground power cables are damaged from being dragged across the pavement or run over with jet bridges. The airport has a mechanism to charge airlines for the repair or replacement of equipment that has been damaged from improper use, as opposed to normal wear. In addition, the jet bridges are not air conditioned. This lack of air conditioning causes cool air from the aircraft to flow into the jet bridge, which inhibits the ability of PCA to cool the aircraft. The airport is considering this factor in the jet bridge replacement project. Drivers for Installation • The airport considers electric PCA and ground power to be a best practice and has airline support.

102 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Finance Strategy • The state will fund new jet bridges through the Florida Department of Transportation and passenger facility charges. Planning and Policy • Jet bridges and equipment are nearing the end of useful life, and a replacement project is planned. • The airport charges airlines for repairs, which provides an incentive to maintain equipment. Tracking and Data Collection on Utilization • Newly installed jet bridges will have equipment for tracking hours of use. • Flights that are diverted through the airport may run APUs. Lessons Learned and Best Practices • Maintain stock of spare parts on site to avoid delays. • Certain PCA and ground power equipment models are less reliable and require more maintenance. 6.15 Zurich International Airport (ZRH), Zurich, Switzerland Background Zurich International Airport in Switzerland is the only non-U.S. airport included as a case study and provides an interesting contrast in the types of equipment, utilization tracking proce- dures, and APU use restrictions in place. Switzerland has stringent environmental regulations, but there are several locations on the airport’s property that do not meet national air quality standards for NO2, PM, and ozone (Fleuti and Ruf 2018). The airport has had air quality mitigation measures in place since the early 1990s and considers the provision of electrical PCA and 400 Hz ground power to be a critical compo- nent of their environmental management efforts (Figure 38). In addition, the airport requires airlines to use the electric PCA and 400 Hz ground power systems as long as they are available and in good working order—or, alternatively, the mobile units—and only rely on APUs in cases when neither is an option (Fleuti and Ruf 2018) (Figure 38A). Airport regulations stipulate that aircraft APUs only be used to start the aircraft engine and be turned on no earlier than 10 min- utes before departure from the gate. Zurich International Airport has both a central chiller plant for the PCA system and central 400 Hz transformers for ground power with point-of-use hookups at the gates (Figure 39). The heating supply for PCA in colder months is provided by the airport’s heating plant. Many gates have equipment necessary to service different sizes of aircraft and can, therefore, be flexible. The airport routinely reports achieving a 99.7 percent serviceability rate (meaning that systems are available and are in an operational and usable state), with high attainment, and that ground crews have consistent ability to connect the aircraft to ground power within 30 to 40 seconds of the aircraft parking (Figure 40). This achievement is due, in part, to the airport’s plant system, which includes a monitoring and control system and a dashboard to monitor the status of the entire system. The dashboard is used by technical staff to identify system perfor- mance, use, and direct maintenance activities. Staff can see when equipment is in use or when a failure has occurred. Ambient and aircraft cabin temperatures are also monitored so that air

Airport Case Studies 103 Figure 38. PCA hoses at Zurich International Airport (Source: Zurich International Airport). Airport Size and Geography Equipment and Utilization ASHRAE Climate Zone: 5A, Cool/Humid • Passengers: 29,396,094 • Passenger growth: 6.3% • Cargo weight: 490,452 tons • Cargo growth: 13.1% • Number of airlines serving: 68 2017 data provided by the airport. • There are 53 pier stands (terminal-connected jet bridges). • All 53 pier stands are equipped with electric PCA and 400 Hz ground power. • There are 15 open stands (i.e., remote aircraft parking positions) with electric 400 Hz ground power. • Flughafen Zurich AG, the airport owner and operator, owns and maintains equipment. • There are 45 mobile, diesel-powered GPU units, and approximately four mobile PCA units are available. Major Tenants Regulatory Issues • Passenger airlines: Swiss International Air Lines, Edelweiss Air, Air Berlin, Eurowings, and easyJet • Cargo: dnata Switzerland and Cargologic • Various locations on airport property exceed Switzerland air quality standards for NO2, PM10, and ozone. • Zurich International mandates that airlines use PCA and 400 Hz ground power when available and serviceable. Figure 38A. Zurich International Airport specifications. temperature can be adjusted accordingly (Figure 41). Maintenance crews can deploy quickly to ramps that are not using the system to determine the cause, (i.e., kinked hose, aircraft cannot accept 400Hz, and so on). The airport has created a variety of resources for airline personnel to reference, including brochures, flyers, and checklists. Brochures cover aircraft ground energy systems at the air- port; flyers provide similar information designed for pilots and airline headquarters staff; and a checklist is intended for cockpit crew members, who are responsible for properly connecting the aircraft itself. In addition, the airline has held workshops with airlines to exchange information and determine the best ways to improve services and systems. The airport also communicates directly with ground crew on the proper use of the gate electrification equipment. To support other airports, Zurich International contributed to the development of AGES–S, available through Airports Council International–World. The Excel-based tool

104 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 39. Aircraft connected to PCA hose and ground power cable at gate (Source: Zurich International Airport). Figure 40. Ground crew plugging in power cable (Source: Zurich International Airport). allows airports to assess the economic and environmental benefits of using electric PCA and 400 Hz ground power instead of aircraft APU under various scenarios. Airports can input their own information—including cost savings and emissions reductions—so that the tool will provide tailored outputs. The tool is useful for conducting cost–benefit analyses but does not assist with utilization tracking. Drivers for Installation • The main motivating factor was the desire to protect local air quality and reduce criteria pollutants and greenhouse gas emissions. • The stringent regulatory environment in Switzerland, combined with the anticipation that ultrafine PM regulation is on the horizon in Europe, add to motivation for gate electrification. • Reduction in noise on the apron from minimizing APU usage is an additional benefit.

Airport Case Studies 105 Figure 41. Initial position of temperature sensor on jet bridge ( left ) and its position in the aircraft cabin (right ) (Source: Zurich International Airport). Finance Strategy • Flughafen Zurich AG funded the system acquisition and installation of the equipment. • The airport owns, operates, and maintains the system. • Airlines are charged for use of 400 Hz ground power and PCA use based on aircraft type and length of time connected to PCA and ground power systems. Rates are both hourly and 2-hour flat rates. – Although the use of electric PCA and 400 Hz ground power saves airlines money on fuel, there is sometimes a disinclination on the part of airline station managers to use the gate electrification equipment because the fees for its use come out of the station budget, as opposed to the corporate fuel budget. Planning and Policy • Airport policy requires that all aircraft connect to PCA and ground power systems if they are available and in service. If these systems are not in service, then mobile units should be used. If mobile units are unavailable, then APUs can be used. There are a few limited exceptions to this rule. • There are mechanisms in place for the airport to further investigate noncompliance with the airport’s APU use policy, including communicating with chief pilots and reporting noncompliance to Swiss regulators. Tracking and Data Collection on Utilization • The airport has an APU violation report form and logs all incidents of noncompliance, which normally occur only a few times annually. • The airport’s building information management system captures information on equipment use (e.g., time, electricity, and natural gas consumed), as well as maintenance records. • The equipment is in service and available over 99 percent of the time.

106 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Lessons Learned and Best Practices • The airport provides support to airlines, including brochures on aircraft ground energy systems at Zurich International, flyers distributed to pilots and airline headquarters staff, and a one-page checklist for cockpit crews concerning connection to systems and on APU restrictions. • A spare parts inventory of components most likely to need replacement—such as PCA hoses, segments, and connections—is useful, since PCA hose damage is the largest maintenance issue. • Airport staff provide training, including workshops, to ground handlers to reinforce proper procedures for using PCA and 400 Hz ground power equipment. • The storage of 400 Hz ground power cables in underground pits helps prevent cable damage and declutters the ramp.