Early tests suggest that this can be done without fouling the boiler, reducing the flame temperature or lowering the ratings of the boiler. The challenge here, of course, is that the biological fuels need to compete directly with the delivered cost of coal this is possible only when fuel is free or inexpensive and transport costs are low. These engines, which draw in part on America's long investment in advanced aircraft engines, are highly reliable and relatively inexpensive. The high technology equipment will, however, require a gas cleaned of particulates and other contaminants. In the longer term, it may be possible to use fuel cells as a conversion device.
Fuel cells have the potential for very low cost, high reliability, and high efficiency.
Moreover, they can be built economically in a variety of size ranges. The optimum size for biomass powered liquid fuel or electric generation is still a matter of intense research. Demonstrations A number of small demonstrations are now underway to test both the technology of producing and converting biomass and the kinds of contractual relationships that can provide a stable market for both producers and consumers of biomass materials. The National Renewable Energy Lab is investigating partnerships with a variety of private firms to commercialize its ethanol production facility. These include a Niagara Mohawk experiment using willows to co-fire an existing coal plant, the Iowa project using switchgrass, the Minnesota Valley Alfalfa Producers project.