Assessment of Conversion Technologies for Bioalcohol Fuel ...

including expansion of conventional grain-based biofuel production (from corn and
soybeans) as well as production from cellulosic wastes and residues and new energy
crops like perennial grasses and trees.
The Bilion Ton Study’s findings, summarized in Figure 4, exceeded its own
expectations, estimating over 1.3 bilion tons of biomass resource potential by “mid-
21 st century” from agricultural and forestry sources. The study did not attempt an
overall assessment of municipal solid wastes, but it did include (among forestry
materials) an estimate of urban wood residues. The study deems urban wood waste
to be the MSW fraction most amenable to bioenergy applications, even though such
material represents only about 13 million of the estimated 230 million tons per year of
MSW generated.
The largest source of waste biomass (nearly one billion tons) is from the agriculture
sector. This agriculture waste is comprised of crop residues (43%); perennial crops
(38%); grains (9%); and animal manures, food processing residues, and other
miscellaneous feedstocks (11%).
Forest materials comprise the remaining 27% of the study’s estimated national
biomass resource potential. About 48% of the 368 million tons of forest biomass
would come directly from so-caled forest “treatment” –thinning and removal of excess
material from forests, reducing the risk of catastrophic forest fires. About 39% would
be secondarily derived from the forest products industry. And the remaining 13%
would be comprised of urban wood wastes.
Figure 4 - Annual Biomass Resource Potential from Forest and
Agricultural Resources (Perlack et al. 2006)
46