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

Transportation’s Role in Reducing U.S. Greenhouse Gas Emissions: Volume 2
sequestration, biomass reforming, or nuclear power sources. Net GHG and other
emissions vary substantially depending on hydrogen production pathways, as well as
hydrogen delivery and storage approaches and may even increase emissions relative to
conventional vehicles under worst case conditions; because HFCVs are more than twice as
efficient as gasoline internal combustion vehicles, however, the overall well-to-wheels
GHG emissions can be significantly lower than other options. For example, estimates
suggest the potential for a 51 percent reduction per vehicle in 2030 and 80 percent in 2050,
assuming that increasingly cleaner sources of energy are utilized for hydrogen production.
Although market penetration estimates and production pathways are highly uncertain,
illustrative GHG reductions are estimated at 52 to 74 mmt CO2e annually in the medium
term (2.3 to 3.2 percent of transportation emissions in 2030) assuming 18 percent
penetration of the light-duty vehicle market and production through natural gas
reformation, and 390 to 470 mmt CO2e annually in the long term (18 to 22 percent of
transportation emissions in 2050) assuming 60 percent market penetration and advanced,
low carbon production pathways by this time.
While the vehicles themselves have the potential to provide excellent performance,
substantial uncertainties exist regarding their long-term fuel storage capacity, fuel cell
stack life, and commercialized cost. At high production volumes incremental HFCV costs
could be between $1,500 and $5,000 compared to conventional vehicles, although nearterm
costs are estimated to be $10,000 or more (see Section 2.8). Cost for fuel cell vehicles
have dropped significantly between 2002 and 2008 and future year hydrogen fuel costs
could even be lower than gasoline, on a cents per-mile traveled basis. However,
development of a widespread, cost-effective fuel production and distribution
infrastructure will be challenging, most likely requiring the development of entirely new
centralized production facilities and dedicated pipelines for transport. No other vehicle
technology/fuel combination evaluated in this study must overcome such significant
barriers in vehicle technology, fuel production, and distribution simultaneously.
Accordingly, the transition costs associated with widescale deployment of hydrogen
within the transportation sector may be higher than most other options.
The government costs for both vehicle and infrastructure have been estimated to be
roughly $1 to $6 billion per year, or $55 billion over 15 years to enable HFCVs to be
competitive in the 2023 timeframe (Greene et al., 2008; NRC, 2008). Regardless of cost,
there remains controversy over the likelihood of overcoming the challenges to widespread
deployment of HFCVs, including hydrogen production, delivery, storage, and fuel cell
performance. Even under aggressive development and deployment scenarios, HFCVs are
unlikely to have a significant impact on GHG emissions for the next decade in the United
States, and other technologies are expected to be more prevalent during that period
(Meyer and Winebrake, 2009). National policies to restrict GHG emissions and encourage
the development of fuel-cell vehicles and hydrogen production and infrastructure will be
necessary to achieve significant market penetration, even in the long term.
Electricity is available for use as a transportation fuel, but the associated vehicle
technology has not advanced enough for battery electric vehicles (BEV) to become
commercially competitive at this time. The GHG benefits of these vehicles are strongly
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