Ministry of Agriculture, Livestock and Food Supply - Embrapa

matter). Thus, the final residue is more appropriate for use as organic fertilizer
because the nitrogen is mineralized and some nutrients are partially solubilized
(SCHERER et al., 1996).
Agroforestry residues
A sizable proportion of the electric power produced from biomass in
Brazil comes from agricultural, forestry and agro-industrial residues. According
to the 2004 National Energy Balance, 2.86% of the electric power in the national
energy matrix comes from biomass: 1.69% from sugarcane bagasse and
1.17% from wood and various agricultural and forestry residues.
The maximum generation potential of the wood and rice sectors is much
smaller and has been estimated at 594 MW for wood and 200 MW for rice, on
average. If only 50% of this potential were used due to economic reasons or
transportation difficulties, about 300 MW and 100 MW would be generated,
respectively. After subtracting the installed capacity – 142 MW for wood residues
and 9 MW for rice hulls – the remaining wood and rice biomass would produce
approximately 160 MW and 90 MW, respectively, in the short term.
Although the identified power generation potential in the wood and rice
industries is rather unimportant in national terms, it is relevant from the regional
standpoint. The wood production and processing centers are located in the states
of Pará, Mato Grosso and Rondônia (native wood) and Santa Catarina, Paraná
and São Paulo (planted forests). In the former case, the future of the forestry
activities is uncertain, so that it would be important to analyze what the actual
prospects are in the context of the sustainable exploitation of forestry resources.
As in all renewable sources of energy, in order to effectively exploit the
electric power generation potential from residual sugarcane, wood and rice
biomass it would be necessary to define and implement medium- and long-term
development policies establishing clear conditions that effectively encourage
businesses to use this economically viable and strategically significant potential.
Forestry residues
Forestry residues obtained through appropriate management of reforestation
projects can increase the energy yield of forests. Here, again, few statistics are
available due to factors associated with regional diversity, such as faunas,
technologies, soils, and climates. Nevertheless, Woods and Hall (1994) estimated
the energy potential of forestry residues in the world at 35 EJ/year (10GW). A
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