Transportation's Role in Reducing U.S. Greenhouse Gas Emissions ...

Transportation’s Role in Reducing U.S. Greenhouse Gas Emissions: Volume 2
same fuel technologies, 0.17 mmt CO 2 could be saved annually. 40
be greater with the use of less carbon-intensive alternative fuels.
Future reductions could
The potential for GHG reduction from transportation agency buildings is not well
understood due to a lack of data on energy efficiency implementation in buildings. It is
estimated, however, that if 100 percent of State DOT buildings implemented energy
efficiency measures contributing to the LEED Silver rating, resulting in a 33 percent
energy savings in buildings, GHG could be reduced by 1.7 mmt CO 2 annually (Cambridge
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Systematics, 2009b). The rate at which these benefits could be achieved will depend
upon the renewal of building stock as well as measures to retrofit existing buildings.
The combined GHG reduction estimates from the construction, fleet vehicle, and energy
efficient building practices described above are about 2.2 mmt CO 2e annually in 2030. The
GHG reduction from work zone management is extremely difficult to quantify because of
the large variation in the amount of traffic created in work zones and the effectiveness of
work zone management techniques on this traffic. Comprehensive national estimates
have not been produced.
Cost-Effectiveness
The cost-effectiveness of alternative fuels is discussed in detail in Section 5.0. According
to a 2009 McKinsey and Company report the cost-effectiveness of a “new building
efficiency package” for commercial buildings is about $13 savings per metric tonne CO 2e
reduced. The McKinsey report also examines retrofitting existing buildings with new
HVAC, water heaters, lighting, appliances, and building envelopes. The cost-effectiveness
of these retrofitting measures range from +$60 to -$120 per metric tonne CO 2e reduced
(McKinsey and Company, 2009).
The cost-effectiveness of construction emission reduction practices has not been estimated.
The cost-effectiveness of work zone management is difficult to quantify due to varying
benefits depending on the severity of the traffic congestion created by the work zone, and
no comprehensive estimates have been developed.
Cobenefits
Construction emission reduction practices have primary been implemented in order to
reduce emissions of criteria pollutants and improve air quality in the vicinity of
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The estimate assumes continuation of the existing mix of alternative fuel vehicles, which includes
about 70 percent ethanol (E85) vehicles with most of the remainder compressed or liquefied
natural gas.
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The LEED standard does not specifically require energy efficiency measures, although most
buildings subject to certification include such measures. Data from Turner and Frankel (2008)
suggest that LEED certified buildings have about 33 percent lower energy use than uncertified
buildings.
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