Petroleum use, greenhouse gas emissions of U.S. automobiles could drop 80 percent by 2050

development all face serious technical challenges.

When hydrogen is used as a fuel cell in electric vehicles, the only vehicle emission is water. Varying amounts of greenhouse gases are emitted during hydrogen production, however, and the low-greenhouse gas methods of making hydrogen are more expensive and will need further development to become competitive. 

Hydrogen fuel cell vehicles could become less costly than the advanced internal combustion engine vehicles of 2050.  Fuel cell vehicles are not subject to the limitations of battery vehicles, but developing a hydrogen infrastructure in concert with a growing number of fuel cell vehicles will be difficult and expensive, the report says.

The technology advances required to meet the 2050 goals are challenging and not assured.  Nevertheless, the committee considers that dramatic cost reduction and overall performance enhancement is possible without unpredictable technology breakthroughs.  Achieving these goals requires that the improved technology focus on reducing fuel use rather than adding greater power or weight, the report says.

It is impossible to know which technologies will ultimately succeed, the report says, because all involve uncertainty.  The best approach, therefore, is to promote a portfolio of vehicle and fuel research and development, supported by both government and industry, designed to solve the critical challenges in each major candidate technology.  Such primary research efforts need continuing evaluation of progress against performance goals to determine which technologies, fuels, designs, and production methods are emerging as the most promising and cost-effective.

Overcoming the barriers to advanced vehicles and fuels will require a rigorous policy framework that is more stringent than the proposed fuel economy standards for 2025.  This policy intervention could include high and increasing fuel economy standards, R&D support, subsidies, and public information programs aimed at improving consumers’ familiarity with the new fuels and powertrains.  Because of the high level of uncertainty in the pace and scale of technology advances, this framework should be modified as technologies develop and as conditions change.

It is essential that policies promoting particular technologies to the public are not introduced before these new fuels and vehicle technologies are close to market readiness, and consumer behavior toward them is well understood.  The report warns that forcing a technology into the market should be undertaken only when the benefits of the proposed support justify its costs.

The study was sponsored by the U.S. Department of Energy’s Office of Efficiency and Renewable Energy. 

— Read more in Transitions to Alternative Vehicles and Fuels (National Academies Press, 2013)