The Australian reports that West Australian Planning and Infrastructure Minister Alannah MacTiernan is visiting the Oak Ridge National Laboratory (ORNL) in Tennessee this week. The reason Minister MacTiernan is visiting ORNL is that she is apparently less than enthusiastic about Australia’s gradual switch to diesel fuel or ethanol as a petrol extender. She is concerned about diesel particulate emissions and says crop-based ethanol is expensive and not necessarily the answer to reducing dependence on fossil fuels. The fact that ORNL are researching the possibility of using metal nanoparticles as a fuel for the future has obviously attracted the Minister’s attention.
David Beach, leader of the Materials Chemistry Group in ORNL’s Chemical Sciences Division, believes metallic nanoparticles may be even more promising candidates than hydrogen as a long-term solution to the rising cost of transportation fuels.
He predicts that a car with a modified engine powered by boron powders could drive three times as far as today’s gasoline-powered internal combustion engine. Metal fuels, he adds, also offer great potential for unmanned vehicles and battlefield power sources for military uses.
Like hydrogen, a metal fuel is an energy carrier and burns cleanly. But unlike hydrogen, metal fuels—such as iron, aluminum, and boron—possess a higher energy content per unit volume, can be stored and transported at ambient temperatures and pressures, reach combustion at high efficiency in a heat engine, and avoid the high costs of fuel cells.
Beach says that the exhaust gas of metal fuels in a heat engine, such as a gas turbine or Stirling engine, is very clean.
We take the oxygen out of the air, leaving nearly pure nitrogen. We recover most of the heat using a recuperator and get much closer to the highest efficiency theoretically achievable in an engine.
An even better energy carrier would be boron, but only if boron nanoparticles could be made at a reasonable cost. Boron is three times better than gasoline in terms of heat per unit weight and heat per unit volume.
Filed under: Alternative fuel |