Assessment of Conversion Technologies for Bioalcohol Fuel ...

For all of the biomass resource categories covered, the Billion Ton Study incorporates
growth factor assumptions on top of present-day resource inventories, along with other
assumptions intended to result in a single realistic estimate of producible biomass.
The authors suggest that this estimated national biomass resource potential “can be
produced with relatively modest changes in land use, and agricultural and forestry
practices. This potential, however, should not be thought of as an upper limit. It is just
a scenario based on a set ofreasonable assumptions.”
California’s Biomass Resources
California’s biomass resource potential has been the subject of a series of studies
conducted by the CEC and other organizations since the early 1990s (Tiangco, et al.,
1994). The 1999 CEC inventory was intended to quantify the gross amounts of
biomass produced in the state annually, not what could realistically be expected to be
collected and delivered for bioenergy production or other beneficial uses (Blackburn,
1999). Thus the 50 plus million tons per year overall estimate was conditioned with
the statement that “the actual amount of residues available wil be significantly lower
once economic, technological and institutional factors are considered.” The CEC
inventory did not attempt to project potential future growth in the estimated biomass
resources, but suggested that some categories of biomass wastes and residues would
be expected to increase while others might decrease.
More recently, in 2004, the California Biomass Collaborative (CBC), under
sponsorship of the CEC, conducted An Assessment of Biomass Resources in
California (Jenkins et al., 2005). CBC also provided an update of this work to support
the Commission’s 2005 Integrated Energy Policy Report (Jenkins, 2005). TheCBC’s
assessments represent the most detailed inventory of the state’s biomass wastes and
residues to date, with the most specific sub-categorization of these biomass resources
and including a county level resource distribution. The CBC 2005 biomass resource
estimate is summarized in Table 6. The gross resource estimate is said to have an
uncertainty factor of about 10 percent.
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