2. Household woodfuel consumption patterns
2.1 Household woodfuel dependency
2.2 Annual household and per capita woodfuel consumption pattern
2.3 Consumption patterns and environmental and socio-economic factors
2.3.1 Consumption patterns by ecological zone
Woodfuel consumption patterns analysis covers household woodfuel dependency, consumption per capita and its variation, under different socio-economic and environmental factors prevailing in Northern Sudan. Four major factors will be considered covering income education, urbanization and ecological zone.
Dependency is defined by the percentage of households using firewood, charcoal or both.
At the national level the survey results clearly indicate a high dependency rate by households in Northern Sudan. Table 2.1 below presents the survey results:
Table 2.1
Household depending on woodfuel
(Percentage Households)
Household |
Firewood |
Charcoal |
Firewood and/or charcoal |
Urban |
65.6 % |
88.9 % |
97 % |
Rural |
85. 1 % |
32.3 % |
93.6 % |
N. Sudan |
79 % |
50 % |
94.8 % |
Source: Wood Consumption Survey 1994.
(a) In aggregate household dependency in N. Sudan is generally high totalling on average (94.8%). urban households dependency (97%) is slightly higher than for rural households (93.6%). This situation reflect the greater usage of non-woody biomass by rural households. It also reflect the increased dependency of urban areas on woodfuel due to economic hardships and availability/access to other modern fuels.
(b) Even at the aggregate national level a distinct dependency pattern by woodfuel type tend to emerge. While firewood is more associated with rural households (85.1%), charcoal is mainly an urban fuel with a dependency rate of 88.9%. However despite this generalization, indications are emerging where such patterns are beginning to change. The survey results show clearly that firewood still remains a significant fuel for urban households (65.6% dependency rate). Similarly, there are trends of increased charcoal use by rural households (32.3% dependency). These changes are triggered by socioeconomic and environ mental factors (resource depletion). The significant use of firewood in urban areas, contrary to prevailing premises, can be explained by socioeconomic factors. Files and ranks of urban population continued to be intensively swollen by flows of rural migrants due to drought, economic hardships and civil strife. Such migrations led gradually to the ruralization of urban areas.
Increased charcoal use in rural areas on the other hand seems to he associated with income rises, closeness to areas of commercial charcoal production zones (urban charcoal supply centres) characterized by charcoal abundancy and relative low prices and in areas where firewood collection/supply catchment areas are further distanced (due to degradation and desertification) to permit its economic transport.
(c) At the state level; the survey results except for a few exceptions, a high woodfuel dependency-ranging between 99.3% and 77.9% is exhibited.
(i) High rural firewood dependency compared to urban areas is generally valid for all states. The White Nile state however is the only exception where urban firewood dependency (92.1 %) by far exceeds that for rural households (58.4 %). Rural White Nile state households tend to extensively depend more on agricultural and animal waste than firewood.
(ii) Household charcoal dependency rate generally exhibit the reverse patterns for firewood. Rural populations for most the states (few exceptions) show a relatively low dependency rate when compared to urban households. Exceptions to this pattern include Sennar (82.7%), Gezira (69.8%), Khartoum (69.7%), North Kordofan (49.8%) and Gedaref (44.7%). These are either areas where firewood supply catchments are further away (e.g. Khartoum, Gezira) or near zones of commercial charcoal production zones (e.g. Gedaref, Sennar). Western states are all of particularly low charcoal rural dependency rate ranging between 1.9% (W. Darfur) to 5.1% (N. Darfur). In contrast all these states exhibited the highest firewood dependency rates (99% and 99.4% respectively). These are areas, which in general, fall within the high rainfall or rich savanna areas characterized by their extensive resource base.
Household and per capita woodfuel pattern exhibit distinct variation with urbanization. Table 2.2 presents a national overview for N. Sudan.
Table 2.2
Annual household and per-capita woodfuel consumption .
Household |
Household/year |
Annual per capita | |||
Firewood M3 |
Charcoal Kg |
Firewood M3 |
Charcoal M3 |
Total M3 | |
Urban |
0.78 |
711 |
0.14 |
0.57 |
0.71 |
Rural |
2.08 |
218 |
0.46 |
0.17 |
0.63 |
N. Sudan |
1.67 |
372 |
0.36 |
0.31 |
0.67 |
Source: Wood consumption survey, 1994
(a) While rural households consume on average 2.08 m3 of firewood annually, urban ones consume only 0.78 m3. Charcoal shows the reverse where urban households annual consumption (711 kg) is more than threefold of rural households (218 kg).
(b) Per capita consumption values are consistent with household annual values. Rural firewood per capita (0.46 m3) is three times that of urban households (0.14 m3). Charcoal per capita shows the reverse (0.57 m3 for urban and 0.17 m3 for rural).
Three major factors will be considered and their effects on household woodfuel consumption patterns will be analysed. These are the ecological zone, income and household education level.
Analysis of woodfuel consumption patterns by ecological zones reflect the impact of natural wood resource scarcity on consumption patterns. It also reflect the pressures to which the rather fragile ecosystems are subjected to. For the purpose of this analysis, Northern Sudan is classified into basically four zones. Desert, semi-desert, low-rainfall and high rainfall zones. Table 2.3 below presents the results of the analysis.
Table 2.3
Annual household woodfuel consumption by ecological zones (1994)
Zone |
M3/household |
Charcoal Kg/household | ||||
Rural |
Urban |
Average |
Rural |
Urban |
Average | |
Desert |
2.00 |
2.51 |
2.06 |
110 |
467 |
149 |
Semi-desert |
1.45 |
0.42 |
0.98 |
340 |
745 |
531 |
law rainfall |
2.39 |
1.27 |
2.15 |
152 |
666 |
270 |
High rainfall |
2.04 |
- |
2.04 |
519 |
- |
519 |
N. Sudan |
2.08 |
0.78 |
1.67 |
218 |
711 |
372 |
Source: Wood consumption survey, 1994.
(a) Desert areas which comprise mainly the Northern strips along the Nile, households consume high quantities of firewood 2.06 M3 year. This is even higher than the figures of the high rainfall areas where the wood resource is more abundant. This amount of high firewood consumption in desert zones should be viewed in the context of` the type of firewood used and the geographical locations where the samples were taken in villages and towns along the Nile. These areas are generally characterized by the sole use of palm trees branches and other fruit tree crops as firewood. This in itself indicates the importance of integrated agroforestry approach on one hand and the need by forest nurseries to broaden their species selection to include fruit trees on the other.
Charcoal household annual consumption in the desert zone is the lowest among all other zones. This is consistent with the absence of the wood resource base within an economic distance to allow the flow of raw materials needed for carbonization under the prevailing technologies. There seems, however, to be wide variations in charcoal consumption in the desert zone with urbanization. Urban household annual consumption for charcoal (479 kg) is more than five folds of rural households (90 kg). Firewood on the other hand shows only slight difference with urbanization.
(b) The semi-desert zone show the highest charcoal household consumption (both for rural and urban) and the lowest household firewood consumption. It is generally heavily populated where most of the densly populated urban centers are found and where irrigated large agricultural schemes are developed. The natural forest resource base is poor and hence dependency on distant supply catchment areas southwards. This offers an explanation to their high charcoal dependency and/or consumption. Firewood however still remains a significant woodfuel in rural areas of the semi-desert zone comprised mainly of bushes and small tree branches. Urban household firewood consumption is however the least in the country.
(c) Low rainfall savanna areas are characterized by medium-high annual household consumption patterns for both firewood and charcoal. In fact it exhibited the highest annual household firewood consumption in rural areas of N. Sudan (2.15 m3 Low rainfall savanna areas are generally areas where low grade (branches/bushes) firewood is relatively abundant; and where traditional commercial charcoal production zones associated with agricultural expansion tress clearance was heavily practiced. Present trends however with accelerated tree resources depletion, show the gradual shift of semi-desert household consumption patterns.
The consumption patterns of the semi-desert and low rainfall savanna areas have the most significant impact on the woodfuel resources base due to their high population density, degree of urbanization and charcoal dependency.
(d) High rainfall areas from the present survey exhibit a high household annual consumption for firewood and charcoal. The high firewood consumption is consistent with both the dominant culture (pastoralism) of firewood use only and the availability and accessibility of the wood resource base which characterize this zone. The high charcoal consumption pattern is not consistent and must be questioned. The sampling limitation to a charcoal commercial production site need to broadened to include other high rainfall sites to correct or confirm this anamoly.
(e) Annual per capita consumption data by ecological zone show similar tendencies as shown by household annual consumption for firewood and charcoal as presented in table 3.4 below. Low rainfall has the highest woodfuel per capita (0.70 M3), followed by the semi-dessert (0.64 m3 high rainfall (0.63 m3 and the desert areas with the lowest woodfuel per capita of 0.56 m3
Table 2.4
Per capita consumption by ecological zone
Firewood M3 Roundwood |
Charcoal M3 Roundwood |
Firewood M3 + Charcoal Average | |||||
Rural |
Urban |
Average |
Rural |
Urban |
Average |
||
Desert |
0.42 |
0.53 |
0.43 |
0.09 |
0.42 |
0.13 |
0.56 |
Semi-desert |
0.31 |
0.07 |
0.20 |
0.30 |
0.60 |
0.44 |
0.64 |
Low Rainfall |
0.53 |
0.25 |
0.47 |
0.14 |
0.54 |
0.23 |
0.70 |
High Rainfall |
0.32 |
0 |
0.32 |
0.31 |
0.3 |
0.31 |
0.63 |
N. Sudan |
0.46 |
0.14 |
0.36 |
0.19 |
0.57 |
0.31 |
0.67 |
Source: Wood consumption survey, 1994.
Three income levels were defined by the survey. These are low (<150000), medium (Ls. 150 000 - Ls. 30 000) and high (Ls. 7300 000) income households. Analysis of household annual woodfuel consumption by income is presented in table 2.5 below.
Table 2.5
Annual woodfuel consumption patterns by households income (1994)
Household |
Firewood M3/household |
Charcoal Kg/household | ||||
Low Income |
Medium income |
High income |
Low |
Medium |
High | |
Urban |
1.06 |
0.98 |
0.81 |
373 |
616 |
855 |
Rural |
2.66 |
2.31 |
1.89 |
57 |
238 |
480 |
N. Sudan |
2.36 |
2.03 |
1.65 |
218 |
454 |
711 |
Source Wood consumption survey, 1994.
(a) There is a clear association between woodfuel consumption patterns and income level for both rural and urban households. It is reflected in both the magnitude of consumption and the fuel mix (firewood versus charcoal) patterns. The general trend shows that while firewood consumption decreases with income rise, charcoal consumption shows the reverse and generally increases with income.
(b) The survey data reveals a 30% drop in annual rural household firewood consumption as they move from the low to the medium income ladder. The drop in consumption decreases to 13% as income shifts from the medium to the high level. similar phenomenon is exhibited by urban household firewood consumption.
(c) The rise in charcoal consumption with income is much significant particularly in rural areas. High income rural households consumption is about eight folds of low income ones. This indicates substantial charcoal requirements with changes in rural income. For urban households where charcoal consumption is already high, income changes are associated with consumption increases by a factor of 2.5 or 1.7 for high and medium income households - using low income consumption level as basis. This may also reflect opportunities by modern fuel substitution.
(d) Analysis of consumption patterns in the various ecological zones by income level presented in table 2.6 shows the following:
(i) In desert areas where firewood is mostly the fuel used, consumption of firewood increases with income in rural and urban areas. There seems to be-a substitution effect in high income groups in the urban sub-sector. Firewood consumption dropped in urban areas as income rises from medium to high level.
(ii) For the rest of the ecological zones household firewood consumption per year tend to decrease for both urban and rural households with income rises.
(iii) Charcoal consumption patterns by ecological zones with income show tile same tendencies of increased household consumption per year as income rises.
Table 2.6
Annual household woodfuel consumption in ecological zones by income level, 1994
(All household annual consumption)
Ecological Zone |
Rural |
Urban | ||||||||||
Firewood M3 roundwood |
Charcoal Kg |
Firewood M3 roundwood |
Charcoal Kg. | |||||||||
Low income |
Medium income |
High income |
Low |
Medium |
High |
Low |
Medium |
High |
Low |
Medium |
High | |
Desert |
1.55 |
2.01 |
2.94 |
51 |
49 |
361 |
1.51 |
3.37 |
1.91 |
278 |
574 |
430 |
Semi-Desert |
1.89 |
1.44 |
0.93 |
110 |
345 |
651 |
0.40 |
0.41 |
0.43 |
392 |
618 |
840 |
Low Rainfall |
2.57 |
2.36 |
2.05 |
38 |
190 |
374 |
1.17 |
1.23 |
1.36 |
366 |
615 |
904 |
High Rainfall |
1.87 |
2.17 |
1.99 |
0 |
582 |
520 |
- |
- |
- |
- |
- |
- |
N. Sudan |
2.36 |
2.03 |
1.65 |
57 |
238 |
480 |
0.92 |
0.85 |
0.70 |
373 |
616 |
855 |
Source: Wood consumption survey, 1994.
Household education in this analysis is limited to only the head of the household. Six education levels were identified: illiterate, Khalwa (quranic school), preliminary, intermediate, secondary and university. Table 2.6 presents the results of the analysis.
Table 2.6
Annual household woodfuel consumption based on education level of heads of households (1994)
Education level |
Firewood M3 |
Charcoal Kg./year | ||
Rural |
Urban |
Rural |
Urban | |
Illiterate |
2.31 |
1.09 |
153 |
629 |
Khalwa |
2.93 |
1.05 |
159 |
706 |
Preliminary |
1.97 |
0.92 |
361 |
754 |
Intermediate |
1.78 |
0.76 |
426 |
853 |
Secondary |
1.65 |
0.55 |
496 |
751 |
University |
1.36 |
0.43 |
545 |
611 |
N. Sudan |
2.08 |
0.78 |
281 |
711 |
Source: Wood consumption survey, 1994.
(a) There seems to be an association between woodfuel consumption patterns and household education.
(b) Firewood household annual consumption in both rural and urban areas decreases as the level of education rises. It decreased from 2.3 M3 for illiterate households to 1.36 M3 for university graduates (41 %). This decrease however can not be attributed to conservation rather it is shifting to other accessible high quality fuels - mainly charcoal in this case. The only exception to this general pattern is the case of Khalwa education level households whose consumption is higher than in the previous education ladder. This can be explained by their frequent use of firewood for lighting needed to read the quoran.
Similarly firewood consumption in urban areas decreases with rise hi education level from 1 09 m for illiterate to 0.43 m3 for graduates due to shifting to other fuels rather than conservation.
(c) Charcoal consumption shows a different pattern with education level. 1 general in both rural and urban settings there is an increase in consumption with education level rise. This trend applies all through the education levels in rural households - with consumption increasing from 153 kg. per households per year for illiterates to 545 Kg/year for graduates. The case for urban households differs slightly. Charcoal consumption increases with rise of education to a certain level (intermediate school) and then begins to drop gradually with education level rises . This indicates the shift to modern fuels (butagas etc) with certain education levels.
(d) The above apparent trends at national aggregate level are not universally applicable to each situation at state, province or district level. There are cases where firewood consumption tend to increase with education (Northern state). Such differences in trends indicate that other factors with education level (income, accessibility and price of other fuels etc) seem to govern the pattern of household woodfuel consumption.
This refers to per capita consumption of firewood and charcoal. Combined in terms of roundwood requirements. Table 2.7 presents the per capita values for the different states. The following observations can be made.
Table 2.7
Woodfuel per capita for Northern Sudan State! 1994
State |
Firewood M3 |
Charcoal M3 |
Total M3 |
Northern (N) |
0.43 |
0.13 |
0.56 |
River Nile (RN) |
0.27 |
0.16 |
0.43 |
Red Sea (RS) |
0.14 |
0.33 |
0.47 |
Kassala |
0.32 |
0.21 |
0.53 |
Gedaref (GD) |
0.26 |
0.32 |
0.58 |
Khartoum (KH) |
0.08 |
0.56 |
0.64 |
Gezira (GZ) |
0.05 |
0.57 |
0.62 |
Sennar (SN) |
0.20 |
0.54 |
0.74 |
White Nile (WN) |
0.23 |
0.29 |
0.52 |
Blue Nile (BN) |
0.64 |
0.33 |
0.97 |
North Kordofan (NK) |
0.45 |
0.27 |
0.72 |
West Kordofan (WK) |
0.48 |
0.14 |
0.62 |
South Kordofan (SK) |
0.32 |
0.14 |
0.46 |
North Darfur (ND) |
0.82 |
0.10 |
0.92 |
West Darfur (WD) |
0.77 |
0.07 |
0.84 |
South Darfur (SD) |
0.73 |
0.13 |
0.86 |
N. Sudan |
0.36 |
0.31 |
0.67 |
Source: Wood consumption survey, 1994
Note: All in Roundwood timber (solid)
(a) Per-capita consumption for rural woodfuel exhibit wide variations between states and ranges between 0.43 M3 to 0.97 M3 with a national aggregate of 0.7 M3 for all N. Sudan of the 16 states five states are higher than this national aggregate, while values for the remaining eleven states are lower.
(b) In general high woodfuel (charcoal + firewood) per capita values are associated with either intensive use of firewood (N. Darfur, S. Darfur and Est Darfur) or medium to high use of both firewood and charcoal (Blue-Nile).
(c) Areas of the highest charcoal per capita (Gezira and Khartoum) exhibit the lowest firewood per capita. Areas of low charcoal per capita, on the other hand, are characterized by high firewood per capita. This reflects the wide opportunities of interfuel substitution between these two woodfuel types.
(d) States that are characterized by medium-high per capita consumption values for both charcoal and firewood (Blue-Nile) represent regions in transition towards the high charcoal low firewood consumption patterns as their relatively rich accessible wood resources deteriorate. Although such deterioration is showing at an accelerated pace.
(e) Khartoum, Gezira and Sennar states show the highest charcoal per capita. While Khartoum and Gezira are troth in the semi-desert depending on supply catchment areas more than 500 Km away, Sennar, in the low rainfall zone, is relatively close to traditional charcoal commercial production zone.
All western states, except for the semi-desert state of North Kordofan, have the lowest charcoal per capita. These are areas where the cooking and nutritional habits are tuned for the direct use of firewood. In addition they are all located in ecological zones where the wood resources are relatively rich, available and less subjected to deforestation.
The Northern desert state along the Nile also exhibit a low charcoal per capita. This is consistent with the prevailing high dependency on fruit tree branches (palm trees) as household woodfuel.
(f) Western states (except for North Kordofan) show the highest firewood per capita ranging between 0.82 M3 to 0.73 M3 for the three Darfur states. The situation as revealed by the survey for south Kordofan is particularly low (0.32 M3 firewood per capita) and already an additional survey check is currently being undertaken.
(d) Classification of per capita at state level for woodfuel consumption by fuel type and urbanization is presented in table 2.8.
Table 2.8
Classification of woodfuel annual per capita of roundwood for different states
Group |
Firewood M3 roundwood |
Charcoal M3 roundwood | ||||
Low |
Medium 0.31-60 |
High |
Low |
Medium |
High | |
Rural |
RS, KH, RN. GZ, SN, GD, WN. |
N, KA, NK, WK, SK, |
BN, ND, WD, SD. |
N. RN, RS, KA, GD, WN, BN, NK, WK, SK, ND, WD, SD. |
KH, GZ, SN. |
- |
Urban |
RS, KA, GD, KH', GZ, SN, WN, NK, SK, SD. |
N, RN, BN, WK, ND, WD. |
RN. |
N. RS, KA, SN, KH, WN, WK, SK, ND, WD. |
GD, GZ, BN, NK, SD. | |
Aggregate |
RN, RS, GD, KH, GZ, SN. |
N. KA, WN, NK, WK, SK. |
BN, ND, WD, SD. NK, SK, |
N, RN, KA, WN, SN, BN. WK, ND, WD, SD. |
RS, GD, KH, GZ, |
- |
Source: Wood consumption survey, 1994
Analysis of household energy consumption patterns reveals the significant role of woody and non-woody biomass in the provision of energy for the sector. Table 2.9 presents the results of this analysis.
Table 2.9
Per-capita energy consumption in TOE by fuel type for households in N. Sudan (1994)
Households |
Firewood |
Charcoal |
Residues |
Saw dust |
Dukhan wood |
Petroleum |
LPG |
Electricity |
Total |
Urban |
0.04 |
0.09 |
0.005 |
0.0003 |
0.008 |
0.005 |
0.008 |
0.006 |
0.162 |
Rural |
0.14 |
0.03 |
0.003 |
0.0003 |
0.003 |
0.01 |
0.001 |
0.0007 |
0.215 |
N. Sudan |
0.11 |
0.05 |
0.02 |
0.0003 |
0.005 |
0.009 |
0.003 |
0.002 |
0.199 |
% |
55.2 |
25.1 |
10.0 |
0.2 % |
2.5% |
4.5% |
1.5% |
1% |
100 |
Source: Wood consumption survey, 1994
Note (1): |
Conversion used: |
Ton of wood = 0.43 TOE (including Dukhan wood) | |
Ton of charcoal = 0.72 TOE | |
Ton of Residium or sawdust = 0.32 | |
(2): |
M2 = 0.72 ton of wood (airdry) |
(a) In N. Sudan per capita energy consumption in the household sector is estimated to be 0.199 TOE
(b) By fuel type biomass energy (woody and non-woody) contributes the most. Total biomass fuels contribution for household energy needs is estimated to be 93%. The remaining 7% is contributed by modern fuels. Individual fuel type contributions as shown in table 2.9 shows the significant role of firewood (55.2%), charcoal (25.1) and agricultural residues (10%).
(c) There are significant differences between rural and urban households:
(i) In absolute terms rural household energy per capita is generally higher than urban per capita (0.215 toe for rural per capita and 0.167 toe for urban).
(ii) The high contribution of charcoal in urban energy supply. Its contribution to household energy per capita is 55.6% for urban households compared to only 14% in rural households. In contrast firewood share in energy per capita for rural households (65.1%) is much higher than urban households (24.7%).
(iii) Similarly the share of agricultural residue, in rural energy per capita is equivalent to that of charcoal (14%) compared to only 3.1% in urban household energy per capita. The share of modern fuels (LPC, petroleum and electricity) is generally low ranging between 11.7% in urban and 5.4 for rural per capita.
