BIOMASS IN DEVELOPING COUNTRIES
Despite its wide use in developing countries, biomass energy is usually used so inefficiently that only a small percentage of its useful energy is obtained. The overall efficiency in traditional use is only about 5-15 per cent, and biomass is often less convenient to use compared with fossil fuels. It can also be a health hazard in some circumstances, for example, cooking stoves can release particulates, CO, NOx formaldehyde, and other organic compounds in poorly ventilated homes, often far exceeding recommended WHO levels. Furthermore, the traditional uses of biomass, i.e., burning of wood is often associated with the increasing scarcity of hand-gathered wood, nutrient depletion, and the problems of deforestation and desertification. In the early 1980s, almost 1.3 billion people met their fuelwood needs by depleting wood reserves.

Share of biomass on total energy consumption:
Nepal    95 %
Malawi  94 %
Kenya   75 %
India      50 %
China     33 %
Brazil     25 %
Egypt     20 %

There is an enormous biomass potential that can be tapped by improving the utilization of existing resources and by increasing plant productivity. Bioenergy can be modernized through the application of advanced technology to convert raw biomass into modern, easy-to-use carriers (such as electricity, liquid or gaseous fuels, or processed solid fuels). Therefore, much more useful energy could be extracted from biomass than at present. This could bring very significant social and economic benefits to both rural and urban areas. The present lack of access to convenient sources limits the quality of life of millions of people throughout the world, particularly in rural areas of developing countries. Growing biomass is a rural, labour-intensive activity, and can, therefore, create jobs in rural areas and help stem rural-to-urban migration, whilst, at the same time, providing convenient carriers to help promote other rural industries.

FOOD OR FUEL?
A major criticism often levelled against biomass, particularly against large-scale fuel production, is that it could divert agricultural production away from food crops, especially in developing countries. The basic argument is that energy-crop programmes compete with food crops in a number of ways (agricultural, rural investment, infrastructure, water, fertilizers, skilled labour etc.) and thus cause food shortages and price increases. However, this so-called “food versus fuel” controversy appears to have been exaggerated in many cases. The subject is far more complex than has generally been presented since agricultural and export policy and the politics of food availability are factors of far greater importance. The argument should be analysed against the background of the world’s (or an individual country’s or region’s) real food situation of food supply and demand (ever-increasing food surpluses in most industrialized and a number of developing countries), the use of food as animal feed, the under-utilized agricultural production potential, the increased potential for agricultural productivity, and the advantages and disadvantages of producing biofuels.

The food shortages and price increases that Brazil suffered a few years ago, were blamed on the ProAlcool programme. However, a closer examination does not support the view that bioethanol production has adversely affected food production since Brazil is one of the world’s largest exporters of agricultural commodities and agricultural production has kept ahead of population growth: in 1976 the production of cereals was 416 kg per capita, and in 1987 - 418 kg per capita. Of the 55 million ha of land area devoted to primary food crops, only 4.1 million ha (7.5 per cent) was used for sugarcane, which represents only 0.6 per cent of the total area registered for economic use (or 0.3 per cent of Brazil’s total area). Of this, only 1.7 million ha was used for ethanol production, so competition between food and crops is not significant. Furthermore, crop rotation in sugarcane areas has led to an increase in certain food crops, while some byproducts such as hydrolyzed bagasse and dry yeast are used as animal feed. Some experts (Goldemberg,1992) believe that “In fact, the potential for producing food in conjunction with sugarcane appears to be larger than expected and should be explored further,”. Food shortages and price increases in Brazil have resulted from a combination of policies which were biased towards commodity export crops and large acreage increases of such crops, hyper-inflation, currency devaluation, price control of domestic foodstuffs etc. Within this reality, any negative effects that bioethanol production might have had should be considered as part of the overall problem, not the problem.
It is important to mention that developing countries are facing both food and fuel problems. Adoption of agricultural practices should, therefore take into account this reality and evolve efficient methods of utilising available land and other resources to meet both food and fuel needs (besides other products), e.g., from agroforestry systems.

LAND AVAILABILITY
Biomass differs fundamentally from other forms of fuels since it requires land to grow on and is therefore subject to the range of independent factors which govern how, and by whom, that land should be used. There are basically two main approaches to deciding on land use for biomass. The “technocratic” approach starts from a need for, then identifies a biological source, the site to grow it, and then considers the possible environmental impacts. This approach generally had ignored many of the local and more remote side-effects of biomass plantations and also ignored the expertise of the local farmers who know the local conditions. This has resulted in many biomass project failures in the past. The “multi-uses” approach asks how land can best be used for sustainable development, and considers what mixture of land use and cropping patterns will make optimum use of a particular plot of land to meet multiple objectives of food, fuel, fodder, societal needs etc. This requires a full understanding of the complexity of land use.
Generally it can be said that biomass productivity can be improved since in many place of the world is low, being much less than 5 t/ha/yr. for woody species without good management. Increased productivity is the key to both providing competitive costs and better utilisation of available land. Advances have included the identification of fast-growing species, breeding successes and multiple species opportunities, new physiological knowledge of plant growth processes, and manipulation of plants through biotechnology applications, which could raise productivity 5 to 10 times over natural growth rates in plants or trees.
It is now possible with good management, research, and planting of selected species and clones on appropriate soils to obtain 10 to 15 t/ha/yr. in temperate areas and 15 to 25 t/ha/yr. in tropical countries. Record yields of 40 t/ha/yr. (dry weight) have been obtained with eucalyptus in Brazil and Ethiopia. High yields are also feasible with herbaceous (non-woody) crops where the agro-ecological conditions are suitable. For example, in Brazil, the average yield of sugarcane has risen from 47 to 65 t/ha (harvested weight) over the last 15 years while over 100t/ha/yr are common in a number of areas such as Hawaii, South Africa, and Queensland in Australia. It should be possible with various types of biomass production to emulate the three-fold increase in grain yields which have been achieved over the past 45 years although this would require the same high levels of inputs and infrastructure development. However, in trials in Hawaii, yields of 25 t/ha/yr. have been achieved without nitrogen fertilizers when eucalyptus is interplanted with nitrogen fixing Albizia trees (De Bell et al, 1989).

ENERGY VALUE
Biomass (when considering its energy potential) refers to all forms of plant-derived material that can be used for energy: wood, herbaceous plants, crop and forest residues, animal wastes etc. Because biomass is a solid fuel it can be compared to coal. On a dry-weight basis, heating values range from 17,5 GJ per tonne for various herbaceous crops like wheat straw, sugarcane bagasse to about 20 GJ/tonne for wood. The corresponding values for bituminous coals and lignite are 30 GJ/tonne and 20 GJ/tonne respectively (see tables at the end). At the time of its harvest biomass contains considerable amount of moisture, ranging from 8 to 20 % for wheat straw, to 30 to 60 % for woods, to 75 to 90 % for animal manure, and to 95 % for water hyacinth. In contrast the moisture content of the most bituminous coals ranges from 2 to 12 %. Thus the energy density for the biomass at the point of production are lower than those for coal. On the other side chemical attributes make it superior in many ways. The ash content of biomass is much lower than for coals, and the ash is generally free of the toxic metals and other contaminants and can be used as soil fertiliser.

Biomass is generally and wrongly regarded as a low-status fuel, and in many countries rarely finds its way into statistics. It offers considerable flexibility of fuel supply due to the range and diversity of fuels which can be produced. Biomass energy can be used to generate heat and electricity through direct combustion in modern devices, ranging from very-small-scale domestic boilers to multi-megawatt size power plants electricity (e.g. via gas turbines), or liquid fuels for motor vehicles such as ethanol, or other alcohol fuels. Biomass-energy systems can increase economic development without contributing to the greenhouse effect since biomass is not a net emitter of CO2 to the atmosphere when it is produced and used sustainably. It also has other benign environmental attributes such as lower sulphur and NOx emissions and can help rehabilitate degraded lands. There is a growing recognition that the use of biomass in larger commercial systems based on sustainable, already accumulated resources and residues can help improve natural resource management.

Energy contents comparison table.

FUEL	Content of water %	MJ/kg	kW/kg
Oak- tree	20	14,1	3,9
Pine-tree	20	13,8	3,8
Straw	15	14,3	3,9
Grain	15	14,2	3,9
Rape oil	-	37,1	10,3
Hard coal	4	30,0-35,0	8,3
Brown coal	20	10,0-20,0	5,5
Heating oil	-	42,7	11,9
Bio methanol	-	19,5	5,4

FUEL	MJ/Nm3	kWh/Nm3
Sewer gas	16,0	4,4
Wood gas	5,0	1,4
Biogas from cattle dung	22,0	6,1
Natural gas	31,7	8,8
Hydrogen	10,8	3,0

BENEFITS OF BIOMASS AS ENERGY SOURCE
Rural economic development in both developed and developing countries is one of the major benefits of biomass. Increase in farm income and market diversification, reduction of agricultural commodity surpluses and derived support payments, enhancement of international competitiveness, revitalization of retarded rural economies, reduction of negative environmental impacts are most important issues related to utilisation of biomass as energy source. The new incomes for farmers and rural population improve the material welfare of rural communities and this might result in a further activation of the local economy. In the end, this will mean a reduction in the emigration rates to urban environments, which is very important in many areas of the world.

The number of jobs created (for production, harvesting and use) and the industrial growth (from developing conversion facilities for fuel, industrial feedstocks, and power) would be enormous. For instance, the U.S. Department of Agriculture estimates that 17,000 jobs are created per every million of gallons of ethanol produced, and the Electric Power Research Institute has estimated that producing 5 quadrillion Btu’s (British Thermal Units) of electricity on 50 million acres of land would increase overall farm income by $12 billion annually (the U.S. consumes about 90 quadrillion Btu’s annually).  By providing farmers with stable income, these new markets diversify and strengthen the local economy by keeping income recycling through the community.

Improvement in agricultural resource utilisation has been frequently proposed in EU. The development of alternative markets for agricultural products might result in more productive uses of the cropland, currently under-utilised in many EU countries. In 1991, the EU planted 128 million ha of land to crops. Approximately 0,8 million ha were removed from production under the set aside program. A much greater amount is planned to remain idled in future. It is clear that reorientation of some of these lands to non-food utilisation (like biomass for energy) might avoid misallocation of agricultural resources. European agriculture relies on the production of a limited number of crops, mainly used for human and livestock food, many of which are at present on surplus production. Reduced prices  have resulted in low and variable income for many EU farmers. The cultivation of energy crops could reduce surpluses. New energy crops may be more economically competitive than crops in surplus production.

ENVIRONMENTAL BENEFITS
The use of biomass energy has many unique qualities that provide environmental benefits. It can help mitigate climate change, reduce acid rain, soil erosion, water pollution and pressure on landfills, provide wildlife habitat, and help maintain forest health through better management.

CLIMATE CHANGE
Climate change is a growing concern world-wide.  Human activity, primarily through the combustion of fossil fuels, has released hundreds of millions of tons of so-called ‘greenhouse gases’ (GHGs) into the atmosphere. GHGs include such gases as carbon dioxide (CO2) and methane (CH4).  The concern is that all of the greenhouse gases in the atmosphere will change the Earth’s climate, disrupting the entire biosphere which currently supports life as we know it.  Biomass energy technologies can help minimize this concern.  Although both methane and carbon dioxide pose significant threats, CH4 is 20 times more potent (though shorter-lived in the atmosphere) than CO2. Capturing methane from landfills, wastewater treatment, and manure lagoons prevents the methane from being vented to the atmosphere and allows the energy to be used to generate electricity or power motor vehicles.  All crops, including biomass energy crops, sequester carbon in the plant and roots while they grow, providing a carbon sink. In other words, the carbon dioxide released while burning biomass is absorbed by the next crop growing. This is called a closed carbon cycle.  In fact, the amount of carbon sequestered may be greater than that released by combustion because most energy crops are perennials, they are harvested by cutting rather than uprooting.  Thus the roots remain to stabilize the soil, sequester carbon and to regenerate the following year.

ACID RAIN
Acid rain is caused primarily by the release of sulphur and nitrogen oxides from the combustion of fuels.  Acid rain has been implicated in the killing of lakes, as well as impacting humans and wildlife in other ways.  Since biomass has no sulphur content, and easily mixes with coal, “co-firing” is a very simple way of reducing sulphur emissions and thus, reduce acid rain. “Co-firing” refers to burning biomass jointly with coal in a traditionally coal-fired power plant or heating plant.

SOIL EROSION & WATER POLLUTION
Biomass crops can reduce water pollution in a number of ways. Energy crops can be grown on more marginal lands, in floodplains, and in between annual crops areas. In all these cases, the crops stabilize the soil, thus reducing soil erosion. They also reduce nutrient run-off, which protects aquatic ecosystems. Their shade can even enhance the habitat for numerous aquatic organisms like fish. Furthermore, because energy crops tend to be perennials, they do not have to be planted every year. Since farm machinery spends less time going over the field, less soil compaction and soil disruption takes place.  Another way biomass energy can reduce water pollution is by capturing the methane, through anaerobic digestion, from manure lagoons on cattle, hog and poultry farms.  These enormous lagoons have been responsible for polluting rivers and streams across the country. By utilizing anaerobic digesters, the farmers can reduce odour, capture the methane for energy, and create either liquid or semi-solid soil fertilisers which can be used on-site or sold.


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