Charcoal Production

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Challenges and potentials to sustainable charcoal production

Charcoal is a prime source of energy in most African countries, and is a driving force in their economies. Worldwide charcoal production has increased, rising by an annual 3.7 percent from 1990 to reach 44 million tones in 2000: Forests_and_Energy.pdf . Surprisingly, policy makers pay little attention to the ways in which charcoal is produced and sold; whether wood used for charcoal burning is harvested in a sustainable fashion. Without coherent policies, almost all charcoal production, transportation and distribution remains informal and unregulated – leading to inefficient and risky production methods.

The common issues characterizing the charcoal production chain in many African countries comprise:

(i) unregulated/illegal resources
(ii) rampant and systemic corruption
(iii) inefficient conversion technologies 
(iv) a perception that it is a poor man’s business considered ‘dirty’ and economically unattractive
(v) free access to wood resources, leading to deforestation and degradation
(vi) the charcoal business is dominated by a few powerful individuals.

Lessons from eastern Africa's non-sustainable charcoal trade are summarized in the publication: Lessons Learnt from Eastern Africa’s Unsustainable Charcoal Trade. World Agroforestry Centre (2006)

Despite the growing scarcity of wood, charcoal generally remains underpriced by more than 20% to 50%, relative to its economic cost as only the opportunity cost of labour and capital required for charcoal production and transport are reflected. The production price for the raw material wood is often not reflected when wood is exploited from unsustainably managed wooded areas (e.g. open access areas). In addition dues are ineffectively collected. Undervaluation translates into wasteful and inefficient production and consumption, and creates a formidable disincentive for forest management and tree growing (see box). A World Bank Publication from some years ago still correctly illustrates the problems of underpricing and provides methods for estimating adequate woodfuel stumpage values: Fuelwood Stumpage. Financing Renewable Energy for the World’s Other Half

 

Impacts of underpricing charcoal As long as charcoal is not sold at a real market price, investments in improved production/conversion are economically not attractive. Investment costs for improved kilns (metal chimneys etc.) do not pay off as long as wood remains a free resource. Despite training support, charcoal burners eventually abandon the improved technology. This is the main reason why the improved and highly efficient Casamance kiln has been disseminated since 20 years throughout Africa without success. Tree growing approaches stay ineffective, as planting and maintenance costs must be taken into account, when competing with open access resources. Significant subsidies (e.g. Madagascar: 200 to 300 €/ha) are necessary to provide enough incentive. This holds also true for any investments in natural forest management. Substitute fuels such as kerosene must be highly subsidized to be competitive, as is the case in a number of countries, such as Senegal and Chad.

 Problems arise at all stages of the charcoal value chain, so a precise understanding of the charcoal value chain provides an excellent entry-point for shaping sound policy frameworks. It offers an opportunity to the various stakeholders to add knowledge, innovation, capital, and technology at each step or link in the value chain. Sound policy can provide checks and balances, creating more balance within and between the sectors, and supporting the intended overarching goals, such as the Millennium Development Goals (MDGs). 

Other papers highlighting the importance of adopting a value chain approach include: Analysis of charcoal value chains - general considerations; and Policy and Distributional Equity in Natural Resource Commodity Markets: Commodity-Chain Analysis as a Policy Tool

Furthermore, evidence-based analyses of the charcoal value chain provide the opportunity to demonstrate the regional added value of charcoal production and thus help to sensitise policy makers for a source of energy hitherto neglected & left to the informal sector. Examples of study projects, geared towards a comprehensive assessment and analysis of the charcoal production chain, include:

• the supra-regional Chaposa project (1998-2002) investigating the charcoal potential for Southern Africa: sei-international.org/mediamanager/documents/Publications/Climate/chaposa.pdfcoastalforests.tfcg.org/pubs/Char_Southern_Africa_CHAPOSA.pdf
• the National Charcoal Survey in Kenya:
• the study initiated by the Forest Governance Learning Group (FGLG) for Malawi:
• 
  

 

Technological Aspects

For conversion of wood into charcoal people use "kilns". The most common types of traditional kilns are earth or pit kilns with efficiencies ranging between 8% and 12 % (Table 7). Because parameters like the hu­mi­dity of the wood used, kiln size, and process control, play an important role, the relative gain of an improved technology ranges between 5% to 50%. See: http://www.fao.org/docrep/X5555E/X5555E00.htm

Table 7: Efficiencies of various types of kiln
	Production of 1 kg of charcoal from	Kiln efficiency
Traditional Kilns	8- 12 kg wood	8 – 12%
Improved traditional kilns	6 – 8 kg wood	12 - 17%
Industrial production technologies	5 – 7 kg wood	20 – 14%
New high-yield, low-emission systems	3 – 4 Kg wood	25 - 33%

Part of the energy losses during charcoal making are compensated for during end use, as charcoal stoves have higher efficiencies than wood stoves (30% - charcoal stoves versus 10%-15% untended open fire or tripod).The following table gives information on the amount of energy loss in % when introducing improved kilns and/or improved stoves in comparison to the usage of firewood (e.g. there is an energy loss of 73% when charcoal is converted by traditional kilns (efficiency of only 8%) and consumer use stoves with an efficiency of 20%).

Table 8: Energy losses converting woodfuel to charcoal for various stoves
		Stove efficiency
		Traditional		Improved
			24%	30%	35%
Traditional Kilns	8%	73%	68%	60%	53%
	12%	60%	52%	40%	30%
Improved Kilns	14%	53%	44%	30%	18%
	18%	40%	28%	10%	-5%

Publications:

Impacts of Greenhouse Gas and Particulate Emissions from Woodfuel Production and End-Use in Sub-Saharan Africa: http://rael.berkeley.edu/old-site/OA5.1.pdf

Traditional kilns

Aus Seidel 2008

Earth pit kilns

Earth pit kilns are the traditional way of making charcoal in many parts of the world and may represent the simplest technology for charcoal production. In brief, wood is stacked in a pit, sealed with a layer of grass and soil and carbonization is started by igniting the wood at one end. Pit kilns can also be built in small size and thus they are suitable for families and even individuals. In pit kilns also large pieces of wood can be used. However, ventilation may be difficult to control and frequently carbonization is incomplete, producing only low quality charcoal. Further, efficiency is lower than in earth mound kilns. To improve efficiency, pit kilns can be equipped with a chimney which allows the use of biomass other than wood such as coconut shells. Nevertheless, even the improved pit kiln is less efficient than a well-managed earth mound kiln. In addition, pit kilns are labor intensive since a pit must be dug into the ground.

Earth Mound Kiln

This is also a common kiln used for charcoal production. It can be constructed from locally available material. In brief, wood is collected and stacked in the polygonal shape of kiln. The wood is then covered with a layer of grass and the construction is sealed with soil. A small opening allows the control and monitoring of the process. When the kiln has been lit, it requires continuous attention for 3 to 15 days depending on the size. After the kiln has cooled down charcoal can be harvested. The main advantage of this type of kiln is that it can be constructed easily without cost at the harvest site. However, carbonization takes rather long and the process requires continuous attention. In addition, charcoal quality is rather low and efficiency is only between 8 and 15 %. Therefore charcoal production using traditional kilns is associated with high consumption of wood.

Improved kilns

Casamance Kiln

The Casamance kiln was developed in Senegal and is an earth mound kiln equipped with a chimney. This chimney, which can be made of oil drums, allows a better control of air flow. In addition, the hot flues do not escape completely but are partly redirected into the kiln, which enhances pyrolysis. Due to this reverse draft carbonization is faster and more uniform giving a higher quality of charcoal and efficiency up to 30 %. Disadvantages of this kiln type are that it requires some capital investment for the chimney and it is more difficult to construct.

Social, Economic and Environmental Impacts

Charcoal consumption is a very controversial issue, as the transformation process from wood to charcoal results in considerable energy loss, requiring significantly more forest resources to produce the same amount of energy. This has led to many countries imposing bans (Kenya, Tanzania, Gambia etc), but with little success, and charcoal use continues to increase with the pressures of growing urbanisation. Charcoal burns more cleanly than wood or dried biomass, producing higher temperatures and it is cheaper to transport and store. For these reasons, interest in charcoal as a fuel is reviving, and steps need to be taken to promote improved charcoal-making technologies and thus reduce the amount of raw biomass required.

Charcoal production is a labour-intensive process, employing a large number of people at different phases of the process and distribution. It is estimated that charcoal production generates between 200-350 person days of employment per Terajoule of energy, compared to 10 person days per Terajoule for kerosene. Sustainable production of wood-based fuels (particularly charcoal) can support rural development through; locally available, affordable and renewable resources, decentralised processing & production, short transport distances with low risks, potential for short-term efficiency improvements (improved stoves, kilns etc.), it can yield a health-dividend, due to reduced levels of smoke, cleaner combustion and easy handling. To be environmentally beneficial, highly efficient kilns and renewably-sourced fuels are required.

To this end, woodfuel policies need to be designed within the context of a sustainable (rural) development approach, and principles of local control and participation adhered to in the planning process. Comparative advantages of locally produced/managed energy sources must be fully exploited to stimulate regional economic growth. Further ways to shape charcoal policies are described in the following paper: "Shaping charcoal policies: context, process, and instruments as exemplified by country cases".

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Further information:

Manual for Charcoal Production in Earth Kilns in Zambia	http://www.bioquest.se/reports/Pdf%20summaries/Cprodman%20SUMMARY.pdf
Review of Technologies for the Production and Use of Charcoal	http://rael.berkeley.edu/files/2005/Kammen-Lew-Charcoal-2005.pdf
WOODFUEL VALUE CHAINS IN KENYA AND RWANDA Economic analysis of the market oriented woodfuel sector Author: Geoffrey M. Ndegwa (MSc. Thesis, Cologne, September 2010) This research highlights the potential in the woodfuel sector to play a key and significant role in the rural and urban poor economic development of Rwanda and Kenya. Das ist doppelt - hier und unter woodfuel production. was denkst du wo es stehen sollte.
haben wir hier noch informationen zum Charcoal project	http://www.charcoalproject.org/
hat Chris adam noch spannendes wovon wir berichten könnten?