Hydrogen economy still decades away, concludes National Academy of Sciences
11 February 2004
A transition to hydrogen as a major fuel in the next 50 years could significantly change the US energy economy, but technical, economic, and infrastructure barriers need to be overcome, says a new report from the National Academies’ National Academy of Engineering and National Research Council. The report, while not disqualifying hydrogen as a future fuel option, is less optimistic, notably in regards to the timing of the hydrogen transition, than the Bush administration. In the best case scenario, the transition to a hydrogen economy would take many decades, and any reductions in oil imports and carbon dioxide emissions are likely to be minor during the next 25 years, said the committee that wrote the report.
“Our study suggests that while hydrogen is a potential long-term energy approach for the nation, the government should keep a balanced portfolio of research and development efforts to enhance US energy efficiency and develop alternative energy sources,” said committee chair Michael Ramage.
President Bush has announced a $1.2 billion hydrogen fuel initiative which, combined with the existing FreedomCAR program at the US Department of Energy, aims to make it practical and cost-effective to use clean, hydrogen-powered vehicles by 2020. But the new initiative has technological and economic challenges to overcome, and concerns about cost, environmental impact, and safety need to be addressed, the committee said.
Hydrogen can be produced using fossil fuels such as natural gas and coal; renewable energy sources such as wind, organic matter, and sun; or nuclear energy. Currently hydrogen is produced in large quantities at reasonable cost by breaking down natural gas into hydrogen and carbon dioxide. To achieve widespread use of hydrogen, it must be produced cost-effectively either in large plants or in smaller facilities at or near vehicle fueling stations. If the hydrogen is produced in large plants, infrastructure must be put in place to distribute it to fueling stations. And hydrogen storage technologies must be developed for vehicles that will give consumers the range between refuelings that they expect, the committee said.
The report points out that 10% of the natural gas used in the US today is imported and that significantly more will be in the future. Thus, while the most cost-effective source of hydrogen for the long run is probably natural gas, its long-term use as a source of hydrogen would not increase US energy independence, the report says.
While fuel cells are one of the most promising power sources for hydrogen-fueled transportation, their cost must be significantly reduced and their reliability increased, the report says. Fuel cells still have a short lifespan and cost at least 10 times too much to present a cost-effective option in the consumer market. The driving range of a fuel cell car is still only about 50% compared to a conventional vehicle.
Still other barriers are related to new safety systems that must be developed before hydrogen, a flammable and explosive gas, can be used in customer settings.
Producing hydrogen from fossil fuels or using fossil-fuel derived energy results in emissions of carbon dioxide into the atmosphere. To reduce these emissions, large-scale production of hydrogen from fossil fuels, e.g., from coal, would need to incorporate capturing and storing carbon, the report says.
The committee also noted that there will be a lengthy transition period during which fuel cell vehicles would not be competitive with internal combustion engine vehicles. According to an optimistic scenario, assuming hydrogen fuel cell cars hit the US market around 2015, hydrogen cars would claim only a 25% market share around 2027. After first hydrogen cars enter the showrooms, “it will take at least 25 years before it will have any big impact,” said Michael Ramage. Hydrogen cars—which could take over new car showrooms by 2040—might be too late to provide the necessary degree of energy security and to reduce fossil-fuel emissions in time to prevent climate change.
The study was sponsored by the US Department of Energy.
NRC Press release | Full report (online pre-publication version)