Wood Charcoal for Energy in Brazil
Author: Camila Maciel Viana
Edited by: Daniel Provazník
Charcoal comes from wood partial burning. The carbonization is done in masonry ovens with heating and cooling cycles that last several days and depends on human work. Currently, the most advanced ovens are those that have a vapor condensing system and tar heater.
The below figures show wood charcoal ovens (Fig. 1) and the final product ready to be used (Fig.2).
Figures 1 and 2: Charcoal masonry ovens and charcoal aspect after production.
Brazil is one of the few countries that uses charcoal as an energy source due to the low amount of mineral coal deposits and the great wealth of forests. Approximately 12.9% of the country's total energy supply comes from charcoal.
Almost all charcoal produced in Brazil is used internally, stimulated by the steel industry that, in the last 20 years, have used it (86%) as a source of heat and agent for the reduction of iron to pig iron, the main raw material for steel. In fact the Brazilian steel industry, which uses almost exquisitely charcoal is so unique, that it makes Brazil the largest charcoal producer in the world (Leme et al., 2018). The second most relevant utilization as a source of energy is in the domestic use for heating and cooking (9%).
Eucalyptus is one of the best options for the production of charcoal, due to the rusticity, productivity, and characteristics of wood. The Eucalyptus reforestation planned and managed properly produce log trees straight, uniform and wood with specific mass suitable for obtaining good quality charcoal.
Renewable use of charcoal provides an alternative development path to mitigate greenhouse gas emissions by improvement of resource efficiency during the carbonization process. Acquire this status completely will demand to overcome challenges as fighting illegal ovens operating with wood from primary forests (causing degradation) and slave work, as well as process innovation implementation (new technologies available) and new market strategies.
Also, charcoal production processes in Brazil does not re-utilize pyrolysis realeased gases, discharging them to the atmosphere. Consequently, more than 30% of wood energy is wasted, aside from air quality decreasing, producing environmental and social impacts (Leme et al., 2018). If gases combustion fornaces would be included, all the categories of potential environmental impacts would be reduced by approximately 90% in both, circular and rectangular masonry kilns (Santos et al., 2017).
Figure 3: Wood energy generation capacity in Brazil compared to other energy sources: hydro energy, oil, sugar cane, natural gas, mineral coal and uranium (2009).
It is important to note that wood for energy has never received any formal governmental incentives. The use of wood charcoal for energy has mostly increased because of the steel industry necessity, and not exactly for other uses demands. In addition, charcoal production in the country is concentrated in a few regions, especially at those close to the steel industry conglomerates, and where Eucalyptus plantations have incentives to be installed. In terms of the cultivated area intended for the production of charcoal, steel-producing companies have 842.4 thousand hectares of trees planted for economic use, in addition to financially planted by third parties, supporting forestry activity.
Figure 4: Wood Charcoal Consumption by sector (1970 – 2004): Residential (red), Commercial (yellow), Agriculture (gree), Industry (blue) and Total (black).
In 35 years the charcoal industrial consumption oscillated significantly, representing mainly the changes in the steel sector policies, subsidies, and markets strategies. Other uses remained slightly stable.
Figure 5: Wood Charcoal price (Reais/charcoal meter), in Brazil, for the period 1974-2000.
Charcoal price oscillates in coordination to steel prices, coal prices, and dollar prices. In recent years, there has been an increase in the price of wood charcoal due to increases in the price of its substitute (mineral coal), wood prices and for issues related to its unrefined production methods that have lead to environmental and human damages, promoting an urgency of modernization.
In recent days, production has been stagnated due to economic systemic crises the country has been facing, but recovery seems to be on the way.
Among the bioenergy products, only the biofuels ethanol and biodiesel have specific policies in Brazil. No specific policies, incentives or subsidies are explicitly related to wood biomass production for energy as charcoal, yet. Even though, charcoal production and consumption can be mainly submitted to the following policies and projects:
- National Program for Planted Forests.
- The Siderurgia Sustentável project: an initiative aligned with national and state priorities with the objective of developing a sustainable and low-emission steel chain, mainly by stimulating charcoal utilization.
- Sectoral Plan of Reductions of Emissions of the Steel Industry to Charcoal
- Protocol of Sustainability of Charcoal: initiated by the Brazilian Steel Institute and associated companies to encourage the sustainable production of charcoal. There are eight commitments.
Wood charcoal still being an important source of residential heating/cooking in Brazil (we use it for making barbecue, and the demand is quite high). Much of the harvested wood for this production has been illegally logged from the primary forest and processed with rudimentary techniques, exposing workers to considerable risks and, sometimes, slavery. The literature about the production and consumption of residential charcoal is scarce, once its main focus is on industrial utilization.
On the other side, its adoption is surprisingly developed in the industry, mainly at the steel mills which, together with government, are promoting and incentivizing charcoal. For what I could find in this research, perspectives about keep on using charcoal are positives, once its utilization instead of oil can promote carbon emissions reductions. Some project´s laws have been debated, but the pace has been quite slow, following the pace of wood bioenergy discussions at all. The path to sustainability is long, but I expect that in the future its production can be totally sustainable, implementing the already available innovations in the sector (forest management and machinery/ovens technologies) and that a more diversified range of industries utilizes its potential for energy generation.
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