The key to the speed of the reactions is the small droplets. Existing processes for converting volatile fuels, such as ethanol or biodiesel, into hydrogen are slower because the fuels are inside pipes, and it takes up to a second for heat to transfer to them. In Schmidt’s process, the droplets heat up instantaneously–in just a few milliseconds–and the system can be faster, cheaper, and smaller, he says. The speed makes it possible to produce more fuel from a smaller reactor, reducing capital costs and potentially making it practical for a farmer to use a small system on the farm.
Schmidt says the process could probably be adapted to work with other biomass, such as slurries or powders made from grass or wood, which are now difficult to convert into practical fuels for electricity generation or transportation because of their high cellulose content. The ability to create hydrogen and syngas directly from cellulosic sources would dramatically increase the amount of fuel that could be made from waste biomass because it would be possible, for example, to use the whole cornstalk, rather than just glucose derived from corn kernels, for fuel. Other researchers are attempting to genetically engineer organisms to convert grass and cornstalks into liquid fuels such as ethanol (see “Redesigning Life to Make Ethanol”).
Such fuels could help reduce the United States’ dependence on foreign oil and provide a renewable source of fuel that produces no net increase of carbon dioxide in the atmosphere, since the carbon released when the fuel is burned is recaptured by the biomass as it grows.
Krause says that initial applications of Schmidt’s current process will likely be in producing distributed power in small amounts, since utility-scale production will be a challenge. For example, controlling the size of the droplets and the temperature of the system to keep the reactions uniform and to avoid damaging the catalysts will be harder in large systems.
Schmidt says he’s not focusing on commercializing the current technique. His next goal is to develop the system to work with sources of waste biomass. Someday it could be possible to use such a system to generate electricity from lawn clippings.