USA: New technology could bridge gap between petrol internal combustion and fuel cell engines
ArvinMeritor has developed technology it says could bridge the gap between today's internal combustion engines and the promising future of fuel cells, accelerating by many years immense benefits in fuel economy.
ArvinMeritor's new plasma fuel reformer was initially designed as a regenerator for cleaning oxides of nitrogen (NOx) traps found in commercial vehicle diesel emissions systems. However, because the reformer is so efficient at self-generating onboard hydrogen, the technology can also be developed as a bridge technology to fuel cells, as a significant, alternate fuel source for internal combustion engines.
"Gasoline engine combustion can be enhanced to significantly reduce fuel consumption and exhaust emissions, without sacrificing engine performance," a spokesman said. "A combination of the increasingly popular hybrids with hydrogen enhanced combustion engine technology can significantly help approach the fuel efficiency levels of fuel cells sooner.
"In researching and developing vast improvements in emissions technology, [we] found that reliable, on-demand, onboard hydrogen generation is not only a key enabler to enhance engine combustion and improve emissions after-treatment, but it can also help transition the industry to the hydrogen economy."
US standards for the commercial vehicle industry call for the reduction of particulate matter (PM) and NOx emissions from diesel-powered vehicles by 90% or more from current levels, in stages between 2007 and 2010. Similarly strict European standards take affect in 2005 and 2008.
Aimed at heavy truck, light truck and passenger car applications in North America, Europe and Asia, technologies under development include effective applications to meet upcoming near-term diesel exhaust emission regulations. The technologies also include innovative solutions for the increasingly stringent standards mandated for the future.
The plasma fuel reformer technology is being developed in partnership with the Massachusetts Institute of Technology (MIT) and Purdue University. The partnership with Purdue is funded through a $US1.7 million grant from the Indiana 21st century research and development fund.
Applied to emissions systems, the fuel reformer is used to enable NOx traps, which have active coatings within the trap to absorb NOx and prevent it from passing into the atmosphere. To maintain its efficiency, however, the trap must be regenerated regularly by introducing hydrocarbons or hydrogen to the trap's active reagents. In conventional NOx traps, diesel fuel is introduced as the hydrocarbon source, but this approach has considerable disadvantages. Those disadvantages include the difficulty of successful regeneration at low temperatures, a significant diesel fuel consumption penalty and the possibility of unburned diesel fuel passing through to the atmosphere, a phenomenon called diesel "slip."
With the reformer, a hydrogen-rich gas is generated onboard and on-demand, using the vehicle's diesel fuel as a source, and supplied directly to the NOx trap, as required. According to laboratory and field tests, the hydrogen-rich gas has proven to be an outstandingly efficient regenerator of the trap.