"Energy Crops" of super-fast-growing trees, grasses or shrubs could provide a third or more of the world's supply of electricity and car fuel within 30 years, scientists reported.
The idea that wood chips, agricultural waste and specially grown crops can take a major load off the world's energy demand _ and drastically cut use of fossil fuels _ is undergoing a resurgence, researchers said, thanks to a rapid advance in ways to efficiently convert plant material into fuel.
Such notions enjoyed wide popularity in the mid-1970s, but fell out of favor as oil prices steadily dropped and processing techniques failed to pan out.
But Monday at the annual meeting of the American Association for the Advancement of Science, researchers from a wide variety of disciplines described the rapid growth of new ideas and a blossoming of pilot programs.
One program is a joint Swedish-Finnish wood-chip-consumingplant, scheduled to start operation in 1993. The wood will be treated with high-temperature steam and air to transform most of its organic content into a flammable gas that will be fed into a turbine to produce electricity.
A similar advanced-biofuel operation is under construction in northeastern Brazil, to run on wood chips from trees grown on previously deforested land.
In northwestern Oregon, 10,000 acres belonging to the James River Corp. are covered in hybrid poplar trees, provided by a federally financed program at Oak Ridge National Laboratories in a search for economical biofuels. The trees are growing at a rate twice that of natural tree stands.
Proponents of biofuels concede that a lot of land will be needed. Replacing all the transportation fuel used by the United States with biofuel would probably require more than 250-million acres of land.
U.S. farmers already till about the same amount of land for food, fiber and other crops.