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View the documentThe Zambia Charcoal Industry
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View the documentCentre For Alternative Technology, Machynlleth, Wales

The Zambia Charcoal Industry

by SH Hibajehe, EN Chidumayo, and Anders Ellegard

The Zambia charcoal industry

Charcoal is the most important household fuel in urban Zambia. It meets the energy needs of about 83 per cent of urban households. With an urbanization level of 42 per cent, charcoal is the major source of energy for more than a third of the population.

Since 1989, the Department of Energy of the Ministry of Energy and Water Development in Zambia has undertaken a number of investigations in co-operation with the Stockholm Environment Institute, with the aim of assessing the longterm viability of charcoal utilization. It found that deforestation due to fuel production from miombo woodlands is a temporary problem, and that the regenerative capacity of the natural forest system is sufficient to withstand this degradation of the forest land.

The environmental impacts of the charcoal production and utilisation system are minimal and air pollution due to burning brushwood in charcoal production areas is a fraction of that from natural bushfires. The suggestion from initial studies, that the traditional method of charcoal production is less wasteful than previously assumed, has been substantiated.

The living conditions of rural charcoal producers are significantly lower than similar groups in urban areas, or even other rural communities. However it could not be shown that the effects on health resulting directly from working in charcoal production were more dangerous than from other forest occupations.

No adverse health effects could be associated with the use of charcoal in households. However, many housewives are exposed to levels of carbon monoxide (CO) emissions in excess of internationally recommended levels as a result of burning charcoal in traditional mbaulas (stoves). This warrants efforts to design stoves and kitchens which minimize air pollution from burning charcoal.

During a workshop in Siavong, Zambia, recommendations were made to the Zambian Government on a charcoal utilization policy. One such recommendation was that instead of taxing charcoal at the source, and by the forest department, it should be taxed at the point of sale and by the urban authorities. It would be necessary to make sure that the resources gathered from this taxation were returned to the production areas as resources for the management of the woodland, and to improve the situation for the charcoal producers.

Charcoal production

The charcoal used in central Zambia is produced from miombo woodland by the traditional earth kiln method. This method involves tree felling by hand or power saws, cross-cutting, kiln building and covering, wood carbonization, kiln tending and breaking to recover the charcoal.

Wood carbonization

Carbonization is a process by which wood is converted into charcoal by burning with a restricted supply of air, and takes place in four stages: combustion, dehydration, exothermic reactions and cooling. Although all these phases may go on in the kiln at the same time, each log passes through these phases. The time required for each phase depends on the size of the kiln, skill of the charcoal maker, moisture content of the wood and weather conditions.

This traditional technique of charcoal production is estimated to convert 20-25 per cent of wood mass to charcoal (oven-dry basis). The promotion of steel kilns by the forest department has had little success with small-scale producers.

Charcoal use

The majority of households in the urban areas of central Zambia live in low cost, residential areas. Only about 11 per cent of these households have access to electricity compared to 6 l per cent and 92 per cent in medium and high-cost residential areas, respectively. In addition' 60 per cent of households living in electrified homes use charcoal for cooking and water heating because of the lack of suitable electric stoves. About 75 per cent of urban households in central Zambia are wholly dependent on charcoal for cooking and water heating with an average consumption of 1,370kg per year, while households that are semi-dependent on charcoal use 972kg per year.

Ecological impacts

These are tree felling, brushwood burning, kiln covering, wood carbonization, road construction and atmosphere pollution.

Tree felling has a serious effect on wildlife through the loss or fragmentation of habitats. Roads constructed for charcoal transportation bring harmful engine exhaust fumes. Total CO2 emissions in Zambia are estimated at 33.5 million tons per year, and the contribution of urban charcoal burning in central Zambia at 1.6 per cent of this. Although this is a small contribution, 99 per cent of the CO2 accumulates because photosynthetic fixation in deforested areas removes only one per cent in the year following deforestation.

In 1987, traffic emissions of nitrogen oxides were estimated at 6,500 tons. Emissions from charcoal burning in central Zambia were estimated at 2,900 tons in 1990. Charcoal burning released about 54,000 tons of volatile, organic compounds in 1990. All these substances may react in the atmosphere to form smog and ozone which are harmful, polluting substances.

Health aspects of household fuels

Health aspects of charcoal production and use were investigated by interviews. Personal monitoring equipment was used to assess exposure to gases and smoke (particulates) during cooking among urban women cooking with firewood, charcoal and electricity and during charcoal production.

It was found that exposure to smoke and gases were significantly different among firewood, charcoal and electricity users. Firewood users were more strongly exposed to particulates while charcoal users had higher exposure to carbon monoxide (CO). CO exposure among 31 per cent of charcoal users exceeded the WHO Europe recommended maximum levels as compared to 17 percent of firewood users and only two per cent of electricity users.

Table 1: Average concentration of respirable suspended particulates (RSP) and CO during cooking with different fuels

Fuel users

Concentration


Particulates

Carbon Monoxide


(mg RSP/m³)

(ppm)

Firewood users

0.890

8.5

Charcoal users

0.380

13.0

Electricity users

0.240

2.1

Source: Ellegard and Egndua 1992 (Project report No 2)

There were no statistically significant differences in general health indices between the three groups of fuel users in Lusaka. However, the health indices did not include eye irritation due to smoke while cooking, incidence of burns or scalding or the exposure of children to other hazards associated with the cooking place.

In spite of the higher exposure to pollution, investigation of health effects among urban fuel users failed to substantiate a connection between the use of woodfuels and respiratory impairment. It was found that the activity perceived as most problematic was working at the burning kiln, with half of the charcoal producers citing that activity. This suggests that exposure to ashes, smoke, gases and heat during kiln breaking are contributing to the discomfort of charcoal producers.

The economics of charcoal

Out of Zambia's total primary energy supply of approximately 5.85 million tons of oil equivalent in 1990, charcoal accounted for about 33 per cent. The percentage shares of other energy sources were, fuelwood 43 per cent, electricity 10 per cent, petroleum 10 per cent and coal 4 per cent. However, in terms of final energy consumption, when conversion losses are taken into account, the contribution of charcoal to the national energy budget reduces to about I I per cent, which puts it level with the major commercial fuels namely electricity and petroleum. Charcoal accounts for 21 per cent of the energy consumed by households, being second only to fuelwood. Electricity and kerosene are the only other energy sources used by this sector and these fuels contribute only two per cent and one per cent respectively, to meeting the energy needs of households. In 1990, it was estimated that households accounted for over 95 per cent of total charcoal consumption.

Charcoal and the national economy

The demand for transportation and marketing of charcoal nationwide is high. It is estimated that about 740 trucks (old) are regularly involved in charcoal transportation. The annual fuel requirement for charcoal transportation is 11 million litres of diesel. Even so, as a proportion of total consumption of petroleum products, charcoal transportation accounts for only about 1.6 per cent.

In terms of income and employment generation, the charcoal industry is one of the most important industries in Zambia. It is estimated that charcoal production provides full-time employment for about 41,000 people in rural areas. A further 3,500 are employed in transportation and 1000 in marketing and distribution.

The report indicates that people are already practising energy conservation measures. For example, most of the respondents were already extinguishing the fire after cooking and putting a lid on the pot when cooking. However, serving cold meals was not generally considered to be an acceptable alternative.

An increase in capital investment in the form of equipment such as power saws and improved kilns, may raise the production cost while reducing employment in charcoal production. Another benefit of the present charcoal production method is that it involves very little foreign exchange.

Charcoal versus coal briquettes

A comparison of the efficiency with which the two fuels can be used in the mbaula and clay stoves shows that briquettes are more efficient in both stoves.

Table 4 indicates that charcoal is the cheapest fuel, followed by kerosene. Using coal briquettes is 34 per cent more expensive than charcoal. Electricity still remains relatively expensive.

Conclusion

The general conclusion of the Workshop was that the charcoal utilization system appeared viable, functional, and economic from most points of view. The challenge is how to manage and improve the system, in order to avoid having to replace it.

This summary report of the Zimbabwe Workshop is reproduced, with permission, from the SKI Journal, Volume 7, Numbers I and 2 (Stockholm Environment Institute).

Table 2: Comparison of electricity and charcoal as domestic fuels

Electricity

Charcoal

Advantages

Versatile, has many end-uses

Minimal investment

Clean, convenient

Little foreign exchange required

Temperature control

Provides employment to urban and rural poor

Time saving

Traded in quantities suitable to low disposable income

Efficient for cooking and lighting


Stimulates productive home activities and studies


No local environmental damage


Disadvantages

Requires major investment and skilled maintenance

Contributes to deforestation

Requires foreign exchange (70% in Zambia)

Dirty in use

Contributes to rural-urban migration

Slow to ignite and cook

Can be interrupted, sensitive to disturbances

Stoves less fuel-efficient than electric

Dangerous in the kitchen

Erratic availability (seasonal)


Kitchen health hazard

Source Hibajene and Kavema 1993 (project report No 4)

Table 3: Properties of charcoal and coal briquettes

Composition

Charcoal

Coal briquettes

Fixed carbon

72

56

Volatile matter (%)

19

22.7

Ash (%)

9

19.2

Moisture (%)

3.4

2.1

Total sulphur (%)

na

0.76

Calorific value (Net) (MJ/kg)

30.4

25.2

Source: Kaoma and Kasali 1993 (project report No 7)

Table 4: Comparison of monthly costs of cooking with electricity (using low-cost approaches), charcoal and kerosene (September 1992 prices)

Fuel

Stove cost

Energy cost

Sub total

Connection

Wiring

Total

Ratio to charcoal

Charcoal

40

730

770

0

0

770

1

Kerosene

310

570

880

0

0

880

1.14

Briquettes

40

920

960

0

0

960

1.25

Electricity

850

560

1410

1900

1900

5210

6.77

NB. Connections and wiring costs are amortized over 15 years using a discount factor of 50%.
Source: Hibajene and Kavema 1993 (Project report number 5).