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38 CHAPTER EIGHT NEW TECHNOLOGIES, INNOVATION, AND LONG-TERM PAYBACK This chapter discusses emerging technologies, innovative large, underutilized roof areas within the established electrical project delivery, and policy trends that will impact energy effi- grid and uses them for electrical production (Coughlin 2009). ciency at airports in the future. Unique or innovative practices and those with long-term payback included solar PV, wind With large roof areas on terminal buildings, hangers, and energy systems, and high-performance windows. parking structures, and very little shade from surrounding buildings, airport terminal roof tops are often prime can- didates for large-scale PV installations--especially as panel EMERGING TECHNOLOGIES efficiencies increase and costs decrease (Seidenman and Solar Thermal and Photovoltaics Spanovich 2008). As identified more than 20 years ago in the Bruntland report, Quoting California Public Utilities Commission Commis- the technology for solar thermal and solar electric technolo- sioner John A. Bohn, "Unlike other generation resources, these gies is constantly improving and "it is likely that their con- projects can get built quickly and without the need for expen- tribution [to energy production] will increase substantially" sive new transmission lines. And since they are built on exist- (Bruntland 1987, p. 144). ing structures, these projects are extremely benign from an environmental standpoint, with [limited] land use, water, The need for a steady transition to a broader and more sustainable [and] air emission impacts" (California Public Utilities Com- mix of energy sources is beginning to become accepted. Renew- mission 2009, p. 2). able energy sources could contribute substantially to this, partic- ularly with new and improved technologies, but their development will depend in the short run on the reduction or removal of certain Because a private investment group and solar developer economic and institutional constraints to their use (Bruntland pay for installation, all up-front capital costs are avoided; how- 1987, p. 145). ever, agreements are legally complicated and usually require an agreement to purchase power at a fixed rate for 20 years Airport terminals possess distinct advantages that position or more (Coughlin 2009). them well for implementation of solar technologies in the future including large roof areas and limited shading from vegetation. Geothermal or Ground-Source Heat Pumps FresnoYosemite and Phoenix Airports have installed large, Ground-source heat pump (GSHP) is the name for "a broad greater than 1 MW, projects. category of space conditioning systems that employ a geother- mal resource--the ground, groundwater, or surface water-- Although prices for electricity from photovoltaics may not become widely competitive with wholesale prices for electricity from con- as both a heat source and sink. GSHPs use a reversible refrig- ventional generating technologies within the next 25 years, they eration cycle to provide either heating or cooling" (DOE 2007). may be competitive with high retail electricity prices in sunny By replacing old or inefficient direct expansion mechanical regions (EIA and DOE 2009). systems with GSHP, significant savings and additional flexi- bility within the system can be achieved. Power Purchase Agreements for Photovoltaic Systems Very limited use was noted in the survey with only one major airport providing cost data. These data indicated a 2- to In addition to owner-installed and managed roof-top PV instal- 5-year payback and medium level of investment. Other sources lations, alternative leasing models are being tested across the indicated longer payback terms of 4 to 13 years and savings country, with one of the largest being initiated by the utility, of 25% to 30% on energy consumption (Turner et al. 2007, Southern California Edison and their Solar Roofs Program. p. 14; DOE 2008). Southern California Edison or a private corporation will "own, install, operate and maintain" rooftop systems on existing Ongoing improvements at the JNU airport include the addi- commercial or public rooftops, leasing space from and sell- tion of GSHP systems and envelope retrofits. Although the ing power to building owners through contracts known as $1 million cost of the GSHP system is close to 20% of the power purchase agreements. This strategy takes advantage of annual operations budget, a combination of grants, legisla-

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39 tive appropriations, and facility fees coupled with expected savings of at least $80,000 per year in energy costs, mean an expected payback of just over 6 years (Martin 2009). Geo- thermal ice and snow melt systems in exterior pavements are expected to bring additional savings owing to reduced equip- ment maintenance costs, labor, and ice removal chemical expenses (Martin 2009). Box 17 Implementing Geothermal Space Conditioning Juneau International Airport ( JNU) and the surrounding community typically heat with diesel fuel owing to the land- locked geography and therefore are very sensitive to fuel prices. When the airport began evaluating a terminal reha- bilitation and expansion, fuel prices were rising, which made operating costs a determining factor in the decision to install a ground source heat pump or geo-thermal system, one of the first systems in the area. With this system coming on line in the late fall of 2009, the airport is already looking ahead to future improvements. Another geothermal system, this one a horizontal loop field, was installed for a future main- tenance building as the building site was disturbed during a separate earthwork project (see Figures 12 and 13). Bemidji Regional Airport (BJI), located in northern Min- nesota, is taking a similar approach, and utilizing large land areas that airports have available to plan for a geother- mal system. This system will be a vertical well-field installed FIGURE 13 Geothermal system installation. adjacent to taxiways to serve an expanded terminal build- ing, as well as a renovated Aircraft Rescue and Fire Fighting (ARFF) facility. other airports, including Toronto, which built a "three turbine cogeneration plant" (Schwartz 2009). Cogeneration of Heat and Electricity The "use of cogeneration is not a simple decision because of fluctuating natural gas and electric prices and high capital The survey found no use of cogeneration technology by sur- costs" (Turner et al. 2007, p. 6). vey respondents. Literature sources indicated utilization at Micro Wind Turbines Small-scale wind turbine installation, such as PV installation, has been considered as a supplemental energy source for air- port terminals. Currently, their implementation is challenged by low electricity rates, which can significantly extend pay- back periods. As a test case, on-site, parapet-mounted wind turbines were recently installed at MSP Airport. Although long-term data are not yet available, payback periods of greater than 10 years are expected at this time (see Figure 14). Peak Shifting Thermal Storage To avoid paying peak demand charges for energy during FIGURE 12 Geothermal well field. Well fields installed the most intensive months and days of the year, some airport below existing pavements at Juneau International Airport respondents utilize peak-shifting thermal storage. This prac- (Courtesy: JNU). tice takes energy at off-peak times to heat or cool a material