FOCUS ON ... BRAZIL

Feixe

Feixe, the ad hoc bulletin of the Brazilian Dendroenergy Network, presents data and studies on wood energy. There have been six issues to date; the next one is scheduled for December 1998.

For more information, please contact:
Prof. Luiz Augusto Horta Nogueira,
Instituto de Mecânica,
Escola Federal de Engenharia de Itajuba,
Campus Universitário 37,
500-000 Itajuba-MG, Brazil.
Fax: (+55 35) 629 1148;
e-mail: [email protected]

Cenbio

The National Bioenergy Reference Center (CENBIO) was created in 1997 to promote the development of sustainable

biomass utilization for energy, mainly using forest fuels and sugar cane. The centre publishes an interesting bulletin (in Portuguese), Cenbio Noticias, presenting news, business opportunities, information on events and some data on bioenergy flows in Brazil. Two numbers of the bulletin have been issued to date.

For more information, please contact:
CENBIO, Av. Prof. Almeida Prado 925,
Cidade Universitária, São Paulo SP,
05508-900 Brazil.
http://www.iee.usp.br/energia/cenbio/cenbio.html

Bioenergy demand in brazil

With a large expanse of arable land, regular rainfall and a relatively low energy demand, Brazil presents very appropriate conditions for developing an energy system relying on a photosynthetic process of energy conversion. In fact, biomass energy has always been important and, despite the recent change towards an increase in fossil fuels and electricity demand, biomass fuels account for a significant share of the total energy consumption, not only in the residential sector, but also very considerably in industry and power generation.

FEIXE logo

The following tables present the biomass energy scenario in Brazil in terms of its evolution and composition of demand. These data are taken from the 1996 Brazilian National Energy Balance, issued annually by the National Department of Energy Development (DNDE) of the Ministry of Energy and Mines (MME), based on data supplied by state-level agencies which are often public utilities. In the last few decades, most of these former electrical companies have been converted to energy companies, introducing energy planning and market studies departments involved with biomass (the following are considered as biomass: fuelwood [directly used and charcoal], sugar-cane products [alcohol and bagasse], black liquor produced and used in cellulose plants and other industrial biomass residues). It is interesting to observe the progressive transition of biomass demand, from many consumers in the residential sector using low-efficiency stoves, to a significantly lower number of users in the industrial sector, where the equipment is generally more efficient. It is very important to take into account this new profile of biomass demand when discussing a system of demand and supply information.

It is also possible to obtain from the Brazilian National Energy Balance the biomass demand in the main industrial sectors (presented in Table 3). It is interesting to observe the importance of the ceramics industry and the food and beverage industry, which corresponds to two-thirds of the total industrial biomass demand. In the food and beverage industry particularly (excluding the sugar industry, where only bagasse is used as fuel), biomass accounts for about 65 percent of thermal energy demand.

Another way to show the importance of biomass energy in the industrial context is by presenting the magnitude of biomass in each sector's energy demand (Table 4).

As can be seen from Table 2, biomass demand in the residential sector is giving way to modern biomass demand in the industrial and transport sectors as alcohol. This tendency is the result of, on the one hand, the large migration of the population from rural areas to cities and, on the other, the fuel substitution policy adopted until 1985 as a consequence of the oil crisis. (Extracted from: Brazilian data on bioenergy: values and methodology by Prof. L.A. Horta Nogueira, Latin American Network on Dendroenergy (LAND), Escola Federal de Engenharia de Itajubá (EFEI), Itajubá MG, Brazil.)

Aracruz

ARACRUZ Celulose de Brasil, una de las mayores empresas de producción de pulpa de eucaliptos del mundo está estudiando la instalación del sexto generador de electricidad para autosuplimiento de energía.

Logotipo de la ARACRUZ

Actualmente ARACRUZ produce el 75 por ciento de la energía que consume. La idea es llegar al 90 por ciento de autosuplimiento de una demanda total de 158 MW. La empresa pretende reducir sus compras externas de energía de 40 MW a 10 MW.

Según el señor Volnei Remor Hilbert, consultor de asuntos energéticos de ARACRUZ, los costos de inversión para expandir la capacidad de generación será de 30 millones de dólares EE.UU., lo cual representará un ahorro anual a la compañía de 12 millones de dólares EE.UU. Este año ARACRUZ invertirá 1,5 millones de dólares EE.UU. en la modernización de los cinco turbogeneradores existentes, el que adicionara 8 MW a la capacidad actual de generación, reduciendo 20 por ciento en costos de energía.

El proceso de cogeneración de ARACRUZ produce energía eléctrica a un costo significativamente menor que la energía comprada a las empresas generadoras públicas. El costo de compra externa es de 55 dólares EE.UU./MW, mientras que para la cogeneración es de aproximadamente la mitad del precio externo.

Una de las características especiales de la cogeneración en ARACRUZ es que el 94 por ciento de la energía cogenerada proviene de la madera de eucaliptos, que es cosechada por la empresa para la producción de pulpa. Los turbogeneradores a vapor STAL (Sueco) y los AKZ (brasileños-alemanes) de contrapresión y condensación son movidos por el vapor producido en calderas que utilizan varias substancias originadas por el procesamiento de la madera del eucalipto, como el licor negro derivado de la fabricación de la pulpa, la corteza del árbol, además de otros residuos del proceso. Otros combustibles utilizados son gases nocondensables como hidrógeno y methanol derivados de varios procesos de la fábrica de pulpa, además de combustibles norenovables como gas natural y aceite combustible. El siguiente cuadro presenta los combustibles utilizados en la cogeneración:

Según el Señor Hilbert, "Este es un proceso muy limpio y eficiente que depende casi únicamente de las fuentes energéticas existentes en la propia fábrica." (Fuente: Red Latinoamericana Electrónica en Bioenergía; correo electrónico: [email protected])

Para más información,
consulte la página Web de ARACRUZ en:
www.aracruz.com.br