Cover Image

Not for Sale

View/Hide Left Panel
Click for next page ( 29

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 28
28 agencies optimize vehicle movements to reduce delay and Almost all agencies pursuing these strategies are aware fuel usage. Traffic signal preemption and queue jump lanes that they can reduce GHG emissions. More than two- for transit vehicles also reduce idling (46 ). Additional strate- thirds responded that reducing GHG emissions is a factor gies cited by survey respondents include the following: in their agency's decision to pursue fuel-efficiency strate- gies. Ten agencies indicated that GHG emissions are a RTD has an intelligent shifting program for buses, principal factor in their agencies' decisions to pursue fuel- specific to different topographical conditions, to maxi- efficiency improvement strategies for their existing transit mize engine efficiency. fleet (BART, Community Transit, Hampton Roads Transit, The Sunshine Bus Company in St. Johns County, LACMTA, Lee County Transit, Montgomery County DOT, Florida, is switching to smaller vehicles to reduce Sarasota County Area Transit, Sound Transit, Southwest energy consumption. Ohio Regional Transit Authority, and TransLink). A few Chicago Transit Authority is developing a model to agencies noted that reducing operating costs and complying measure and help minimize bus fleet operating costs with environmental regulations are key factors in pursuing and emissions. these strategies. Sound Transit has a midday bus storage program; buses are stored close to the central business district between the morning and afternoon commutes to reduce dead- STRATEGIES TO REDUCE EMISSIONS FROM CONSTRUCTION AND MAINTENANCE head mileage. This program reduces bus fuel consump- tion without changing the amount of service provided. Construction of facilities and infrastructure, as well as main- Agencies may be able to reduce GHG emissions through tenance of facilities, infrastructure, and transit vehicles, is a specific measures targeted at non-CO2 gases. For example, source of GHG emissions. While these activities probably fugitive emissions of CH4 from CNG buses and of HFCs represent a small share of transit agencies' total emissions, from air-conditioning systems also contribute to global they can nonetheless be improved to shrink agencies' GHG warming. Adjusting maintenance procedures may reduce emissions. The strategies discussed in this section apply gen- such emissions from transit vehicles. erally to any industry that provides infrastructure services. There has been little research to date on how these strategies Almost all agencies surveyed are pursuing some strategies apply to transit agencies specifically. Still, a number of agen- that reduce emissions from existing transit vehicles. Table cies are implementing or planning these types of strategies. 8 summarizes survey responses. Nearly three-quarters of agencies surveyed are improving the fuel efficiency of their Agencies can reduce GHG emissions from construction existing transit fleet by implementing anti-idling policies and maintenance in three primary ways: or technologies and by implementing vehicle maintenance programs. Nearly two-thirds are planning or implementing Reduce emissions embodied in any materials used -- driver education programs. Almost half of the agencies sur- This strategy typically involves changing the types of veyed are planning or implementing vehicle engine retro- materials used or the source of materials used. Often, fits to improve the fuel efficiency of their transit fleet. More recycled construction materials have lower embodied agencies are in the implementation phase rather than the emissions, because the energy required to reprocess planning phase of these strategies. waste materials is less than that required to process vir- gin materials. For example, both BART and NYMTA TABLE 8 are planning to use rail ties made from recycled materi- AGENCIES PURSUING VEHICLE OPERATION AND als in future construction and maintenance. Recycled MAINTENANCE STRATEGIES (% of 41 respondents) plastic can be incorporated in bus shelters, benches, Planning or and signposts. Fly ash can be substituted for a portion Strategy Types Planning Implementing Implementing of the portland cement that typically goes into concrete Anti-idling policies to reduce GHG emissions. Materials drawn from local 29% 63% 73% or technologies sources require less energy to transport than materials Vehicle mainte- drawn from farther away. Transit agencies can contrib- 22% 66% 76% ute to lowering overall GHG emissions from the con- nance programs Vehicle engine struction industry by recycling waste from their own 24% 24% 44% construction activities. retrofits Driver education 27% 44% 61% Reduce emissions from on-road transportation of materials, construction workers, and waste --Any Other strategies 17% 20% 29% measures that reduce the amount of materials and 90% waste transported will reduce GHG emissions. Use of Any strategies (37 agencies) biofuels in heavy-duty vehicles that transport materials

OCR for page 28
29 and waste also can reduce GHG emissions. Emissions Almost three-quarters of agencies surveyed are planning from transportation of construction workers can be or implementing strategies to reduce energy consumption reduced by implementing carpooling plans or encour- or GHG emissions from construction and maintenance (see aging workers to use transit. Table 9). Nearly two-thirds of agencies surveyed are tak- Reduce emissions from construction and maintenance ing steps to recycle construction waste. Half are taking steps equipment--Construction equipment and maintenance to use alternative construction materials. About one-third vehicles also typically burn fossil fuels that release of agencies surveyed are investing in changes to their con- GHG emissions. The same types of strategies that can struction equipment, vehicles, or fuels. More than a quarter reduce emissions for transit vehicles, including using are using locally sourced materials. One agency, the Utah biofuels and reducing idling, also can reduce GHG Transit Authority, is developing a sustainability design stan- emissions from construction and maintenance equip- dards program to maximize use of recycled materials in ment. If transit agencies use contractors for construc- construction. tion and maintenance work, these types of strategies may be more difficult to control. TABLE 9 AGENCIES PURSUING CONSTRUCTION AND Portland's TriMet has instituted a number of sustainable MAINTENANCE STRATEGIES (% of 41 respondents) construction practices for a light-rail extension, the Inter- Planning or state MAX Yellow Line. These practices will help reduce Strategy Types Planning Implementing Implementing GHG emissions, and many also save money for the agency. Use of alternative Practices include the following: fuels/technologies 20% 29% 44% in non-revenue Plastic railroad ties --TriMet installed 6,000 plastic vehicles ties made of recycled automobile gas tanks, instead of Changes to con- steel (see Figure 13). struction equipment, 20% 17% 32% vehicles, or fuels Plastic bollards --Interstate MAX is the first light-rail line to use recycled plastic bollards, instead of rein- Changes to con- 0% 0% 0% forced metal stanchions, in the paved trackway. The struction materials recycled bollards saved $100,000 in purchasing costs Use of alternative over steel, and saved an additional $150,000 in instal- construction 27% 29% 49% materials lation costs. Using existing materials--TriMet pioneered an inno- Recycling con- 29% 39% 61% vative practice of using the existing road-base con- struction waste crete and adding a new layer of asphalt. This reduced Sourcing materials 10% 17% 27% demolition, trucking, and disposal fees by nearly $2.4 locally million. Changes to con- Recycling pavement and track--Where the existing struction equip- 0% 0% 0% road base could not be reused, TriMet used recycled ment/vehicles or fuels asphalt and concrete as base materials, recycling enough material to cover a 50-ft wide strip, 5 mi long Other strategies 5% 5% 7% and 1.5 ft deep. These measures resulted in savings of 73% Any strategies $186,000 by buying recycled materials instead of new (30 agencies) materials. All of the agencies planning or implementing these mea- sures are aware that they can reduce GHG emissions. More than two-thirds noted that reducing GHG emissions is a factor in their agency's decision to pursue these strategies. Almost one-third of agencies indicated that reducing GHG emissions was a principal factor in their decision (Southwest Ohio Regional Transit Authority, Jacksonville Transporta- tion Authority, Community Transit, TransLink, Sound Tran- sit, LACMTA, Hampton Roads Transit, Sarasota County Area Transit, Foothill Transit, and TriMet). Sacramento Regional Transit District noted that reducing life-cycle costs FIGURE 13 Recycled plastic railroad ties used in construction was the primary driver of its construction and maintenance of TriMet's Interstate MAX Yellow Line. strategies.