Ministry of Agriculture, Livestock and Food Supply - Embrapa

The average electric power consumption in broiler farms is 2,169 kWh/farm/
month according to the Cemig power company in Minas Gerais, not taking into
account the electric power used to keep the poultry warm. However, when we
also consider the use of electric bell jars to warm the chicks (1,000 W for every
500-chick lot) during the first 21 days of life, consumption rises to 16,128kWh.
The average LPG consumption in the bell jars to warm the chicks in
farms with 16,000 birds (12 x 100 m), in the South Region's cold winter, is
about 546 kg (42 13-kg containers), or R$ 1,260.00 (42 x R$ 30.00) for each
chicken lot in the farm, or a total of R$ 8,820.00 (cost of the LPG container in
October 2004 = R$ 30,00) for seven lots per year.
Souza (2001) observed that the percentage of energy used to warm
the substrate is very high and that it would be possible to improve the efficiency
of the system in a way that would enable the net biogas production to be used
simultaneously for other purposes.
The expansion of swine production in some regions, especially in the
South, has led to the discharge of a significant volume of residues in certain
areas, causing serious concern over environmental degradation and the
resulting impact on the qualify of life.
The search for technologies that help reduce environmental pollution
has been in the agenda of the most varied sectors of society, particularly in
the producers' agenda, with a view to improving and preserve the quality of
life of the population. Because of the legislation, there are growing demands
regarding the criteria used for the management of wastes. The criteria have
become increasingly more rigorous and impose a heavy economic burden
on producers. It is essential that the processes used for treating wastes evolve
and that their cost decrease, so as to make them available to swine farmers.
By combining environmental action – aiming at reducing effluent and
gas emissions – and the creation of a viable and attractive alternative for
swine farmers, well-known innovative companies are building and facilitating
the installation of biodigesters in the swine farms in their network. In exchange,
these companies benefit by collecting carbon credits in the market as a
function of the biodigesters they have had installed. It is estimated that more
than 70 biodigesters have been built recently under such schemes, in addition
to the 320 biodigesters currently being built in the states of Minas Gerais,
Mato Grosso, Mato Grosso do Sul, Santa Catarina, and Goiás.
When submitted to anaerobic digestion in biodigesters, swine wastes
only release carbon as CH 4 and CO 2 (diminishing the C/N ratio in the organic
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