MoreEarlier this year, President Bush singled out hydrogen development as his chief energy priority and, ever since, the fuel has been the new mantra of energy circles. However, in a recent report published by the Journal Science, researchers at the California Institute of Technology caution that widespread use of hydrogen could contribute to damage of the ozone layer.
Congress plans to allocate potentially billions of dollars to hydrogen research, and Secretary of Energy Spencer Abraham recently turned the spotlight on hydrogen as the key to securing the energy supply of Western economies. _At the same time Abraham has been calling for international cooperation in advanced research and development to further the deployment of hydrogen energy technologies. Caltech researchers urge that more work must be done to assess possible environmental risks.
“We have an unprecedented opportunity this time to understand what we’re getting into before we even switch to the new technology,” said Caltech physics research scientist and lead author of the science report Tracey Tromp. If hydrogen were to replace fossil fuel entirely, agree Tromp and other researchers, an estimated 60 to 120 trillion grams of hydrogen would be released each year into the atmosphere, assuming a 10 to 20-percent loss rate due to leakage from pipelines, processing and power plants and fuel cells in cars. This is four to eight times the amount of hydrogen currently being released, possibly resulting in doubling or tripling of hydrogen inputs to the atmosphere from all sources, natural or human.
Ideally, however, a hydrogen fuel cell vehicle presents no environmental threat, the researchers add. Combining hydrogen with oxygen pulled from the atmosphere produces energy, and the tailpipe emission is water. The hydrogen fuel could come from a number of sources (for example, Iceland recently started pulling it out of the ground). Nuclear power could be used to generate the electricity needed to split water, and in principle, the electricity needed could also be derived from renewable sources such as solar power or wind.
The question of whether hydrogen is bad for the environment hinges on whether the planet has the ability to consume excess anthropogenic hydrogen. “If hydrogen emissions present an environmental hazard, then recognizing that hazard now can help guide investments in technologies to favor designs that minimize leakage,” Tromp says.
“On the other hand, if hydrogen is shown to be environmentally friendly in every respect, then designers could pursue the most cost-effective technologies and potentially save billions in needless safeguards.” See www.gps.caltech._edu/news/news.html and www.eere._energy.gov.
View Pollution Engineering's popular 
