Biomass—The Fuel of the Rural Poor in Developing Countries

Bioenergy Options for a Cleaner Environment Ralph E.H. Sims (Editor) © 2003 Published by Elsevier Ltd

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Chapter 6 Biomass - The fuel of the rural poor in developing countries Pradeep Chaturvedi General Secretary, Indian Association for the Advancement of Science pradeepc@giasdie01 .vsnl.net.in

6.1

Introduction

Biomass is traditionally considered to be the fuel of the poor. More than half the world's population lives in rural areas, nearly 90 percent of them - some 2.8 billion - in the developing countries. The vast majority of these people are dependent on the traditional fuels of firewood, dung and crop residues, often using primitive and inefficient combustion technology. This combination barely allows fulfilment of the basic human needs of nutrition, warmth and light, let alone the possibility of harnessing energy for productive and industrial uses which might begin to assist escaping from the cycle of poverty. Most of today's 2 billion people without adequate energy services live in the rural areas. Demographic trends show there is a risk of exacerbating the situation as urban populations are projected to grow rapidly which is likely to reinforce policy makers' pre-occupations with urban issues. Rural poverty will not be eased while increased competition for rural energy supplies continues. The importance of woody biomass varies between regions and also within a region. In Europe and North America, wood contributes about 3% of primary energy taking into account its use by the forest industry. In the industrial countries of Asia and the Pacific, the contribution is about 1.5% and in the former Soviet Union it is about 2-3%. In developing countries with greater rural populations, the proportion of the energy supply met by fuelwood is higher being 10-15% in Asia and Latin America and over 30% in Africa. Divergence in use pattern within a continent is even greater. In South Asia fuelwood contributes around 37% of primary energy, though variations are large between Nepal, where fuelwood contributes over 90% of the total primary energy supply, and in India where it is about 33%) due to increasing fossil fuel consumption. In Africa, excluding South Africa, Egypt and Algeria, wood contributes around 60% of the primary energy supply. However, the annual per capita consumption of fuelwood does not show much deviation between different regions. In developed countries, the wood energy contribution also varies considerably from country to country. In the UK, Belgium and Germany, there is relatively little use of fuelwood while in countries such as Finland, Sweden and Austria, forest energy provides up to 11% of their demand. In France, woody biomass provides a meager 4% of its national energy consumption but the 329 PJ used is similar to Sweden (326 PJ) but here it represents more than 16%) of the total energy consumption. Dependence on traditional biomass fuels will long remain a reality given the high level of demand, but they are being managed and used at a non-sustainable rate. Inefficient technologies and appliances mean that precious firewood resources are wasted and high indoor smoke pollution severely impairs health (Chapters 3 and 5). This is likely to change

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as recent investments in the energy sectors of developing countries have targeted fossil fuel resources and relatively modest investment has been made in the dominant traditional biomass energy resources. 6.2

Fuelwood Use

The Food and Agricultural Organisation of the United Nations (FAO) has developed a brief and concise definition of different fiielwood types used for domestic cooking and heating (Table 6.1, FAO, 1995). Table 6.1 - Fuelwood classification, descriptions and examples Fuelwoods Indirect fiielwoods Recovered fuelwoods

Wood-derived biomass fuels

Brief description Mainly solid biofuels produced from wood processing activities Wood used directly or indirectly as fiiel, derived from socio-economic activities outside the forest sector Liquid and gaseous fuels produced during forest activities by the wood processing industry

Examples Barks and sawdust from wood mills Used wooden containers, pallets Black liquor from pulping of wood

In many cases, woody biomass is not directly combusted but processed and transformed into more convenient solid fuels, such as chips and pellets. The general physico-chemical characteristics of the wood, however, remain basically unchanged. In other cases, wood is transformed into secondary solid, gaseous and liquid fuels of which charcoal (or "char") is perhaps the most typical case. These secondary fuels are prepared to meet the special needs of industrial users (as in the case of charcoal use in the iron and steel industry) or to improve their transportability and storage (as in the use of charcoal for urban households). In other cases, the wood can be transformed into gaseous producer gas and liquid fuels (methanol, ethanol) in order to meet the special energy needs of industrial and transport sectors (see Chapter 4 for details). The main inter-related factors which influence the future role for wood energy are macro factors at the national level and micro factors at the specific site or household level. The major key determinants in energy demand patterns at the national level include: • • •

economic performance; population growth and rate of urbanization; and technological advancement.

The micro factors at the individual household level include: • • • •

fuel preference, cost and performance of end use devices, cost of fuel, and availability of fuel.

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Leach & Gowen (1987) identified that an examination of household energy consumption surveys showed that energy use and the choice of fuels used in households depended on two sets of variables. •

Supply variables - price and availability of commercial fuels (though much biomass used in developing countries is scavenged, not purchased); abundance or scarcity of fuelwoods; access to fuels by different groups; seasonal variation in supply; fuel preferences (between traditional fuels, and traditional fuels versus modem fiiels); and settlement size and proximity to large towns or cities.

•

Demand variables - household income; household size; ambient temperature; local precipitation (for space heating and drying needs); cultural factors (diet, cooking and lighting habits, number of meals, feasts and burial rituals); and cost and performance of end-use conversion devices.

6.2.1

The fuelwood gap theory of the 1970s

The "Fuelwood Gap" theory first surfaced in 1973/74 when oil became a more precious commodity. Both demand side and supply side interventions in the biomass sector were greatly affected by the so-called fuelwood crisis of developing countries. The rapid rate of deforestation in these countries was already recognized. Energy analysts and social scientists began to accumulate evidence across the developing world about the scale of fuelwood use and the difficulties faced by millions as tree stocks declined. It seemed natural to regard both the oil and fuelwood crises as essentially similar. The fuelwood problem seemed to be a classic case of rising energy demand outstripping supply. Although biomass resources are in theory renewable, they are being consumed at non-sustainable rates in many areas. The fuelwood 'gap' analysis came to dominate almost every attempt to measure the scale both of the fuelwood crisis and the remedies which would be needed to alleviate it. The basic premise of the gap theory was that fuelwood consumption was the principal cause of deforestation, and therefore, of mounting fuelwood scarcities. To measure the scale of this imbalance, estimates needed to be made of the consumption of fuelwood, and sometimes of timber, construction poles and other tree products, in a given region and then compared with the standing stocks and their annual growth. Typically it was found that consumption greatly exceeded the annual growth of all the trees in the region. For instance, studies of the Sahelian countries found that fuelwood use exceeded the growth rate by 70% in Sudan, 75% in northern Nigeria, 150%) in Ethiopia and 200% in Niger, with, conversely, a small surplus of 35% in Senegal. The next step was then to project the gaps to meet basic needs. Since consumption had to be met from somewhere, it was assumed that the shortfall would be filled by cutting into tree stocks. Fuelwood consumption was projected, usually in direct proportion to population growth, and calculations were made of the tree stock remaining each year. Developing countries had no financial resources to assess and analyse their supply situation at the time. International development agencies provided finance and numerous studies have been carried out since the "Nairobi Conference on Renewable Energy" in 1981. Lower income households and the commercial and small industrial sectors had never been

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systematically surveyed before. Nevertheless, much of the assessment and analysis made to date has been more qualitative than quantitative. As a result, in the first half of the 1980s all UNDP/World Bank Energy Sector Assessments for developing countries used analytical methods based on the fuelwood gap theory. The gap theory w^as the basis of an FAO study conducted in the early 1980s and estimated that just over one billion people were living in areas of fuelwood 'deficit' because they were cutting trees to meet their energy needs at a faster rate than the trees could re-grow. It projected this number would double to two billion within 20 years. The same approach underpinned many other widely quoted reviews of Africa's and Asia's fuelwood problems, and was being used even as late as 1988 by major donor agencies to justify the planting of large-scale forestry projects in Africa. However, experience over time revealed fundamental flaws in the assessment method used to define the fuelwood problem. The trees outside the forests, such as those around homesteads, along roadsides, within villages and on agricultural land, which were and remain the primary sources of fuelwood for rural people, were not included in any of the analyses. This remained a major lacuna in the World Bank Study which proved to be incorrect. However the World Energy Council (WEC, 2000) is now concerned that 2 billion people still have no access to commercial sources of energy.. 6.2.2

Resulting actions

A series of studies and meetings during the 1970s culminated in The Eighth World Forestry Congress in 1978 on 'Forest and People'. In the same year, the FAO published "Forestry in Rural Development" in which community forestry was defined as any forest activity which intimately involves local people including: • • • •

producing logs in areas that are short of wood and other forest products; growing trees as cash crops; processing forest products at the household, artisan or small industry level; stimulating the activities of forest dwelling communities.

It excluded large-scale industrial forestry and any other form of forestry that contributes to community development solely through employment and wages. The World Bank, in their 1978 Forestry Sector Policy Paper, acknowledged that past approaches to woody biomass forestry had been inadequate and too narrowly focused to be of any real help towards meeting the energy needs of the urban and rural poor in developing countries. Fiscal measures to encourage fuel switching were implemented to avert the fuelwood crisis with the belief that pricing fuelwoods at their true economic value would encourage households to substitute them with liquefied petroleum gas and kerosene, thus allowing the market to solve the de-forestation threat. However, the fiscal policies employed failed to achieve that and: • •

fuelwood taxes, and prices remained low; tax collection performance was poor; and

Biomass

•

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the expected market solution to the fuelwood crisis through substitution did not materiaHse.

Biomass end-use efficiency was also implemented to ensure that sufficient supplies remained available for traditional rural use. It included the following benefits: • • • • • • •

conserving energy; reducing the time spent on collecting firewood; expanding economic opportunities for both rural and urban families; empowering women; reducing harmful household smoke exposure; reducing forest clearing and its ecological consequences; and mitigating global atmospheric pollution.

As a result fuelwood production increased due to the focus on growing commercial plantations on non-forest lands and to the social approach which caused the demand to decrease due to improved efficiency of use. However, the economic measure did not show any perceptible change. The overall effect was that fuelwood availability is projected to have sufficient quantities for the foreseeable future. 6.2.3

Negation of fuelwood gap theory

The FAO's Regional Wood Energy Development Programme for Asia and Pacific (RWEDP, 1996) published a study based on data collected in the participating countries. It estimated that two-thirds of the fuelwood supply came from trees other than those growing in forests. The same study also indicated that sources of fuelwood were increasing and total fuelwood consumption was not rising in proportion to the population, but was being delinked mainly due to technological advances in combustion devices. This study negated the "fuelwood gap theory". 6.3

Biomass Use Status

Commercial use of biomass can be estimated at between 10% and 30% of total biomass use at around 9 EJ ± 6 EJ/year. Since the early 1990s biomass has gained considerable interest world-wide for the following reasons: • • • • • •

it is carbon neutral when produced sustainably; its geographic distribution is relatively even; it can be grown close to where it is used; it has the potential to produce modem energy carriers that are clean and convenient to use it can make a large contribution to rural development; and its attractive costs (compared with imported fossil fuels) in many developing countries make it a promising energy source.

Commercial modem biomass energy systems are being developed in many countries and the contribution of biomass to the world's energy needs is expected to continue to grow for 50 to 100 years (Table 6.2).

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Table 6.2 : Predictions of the potential contribution of biomass to the world's energy supply during this century

Source

RIGES SHELL World Energy Council Greenpeace IPCC

Time frame (year) 2025 2050 2060 2050 2100 2050 2100 2050 2100

Total projected global energy demand EJ/y 395 561 1,500 900 671-1,057 895-1,880 610 986 560 710

Contribution of biomass to global energy demand EJ/y 145 205 220 200 94-157 132-215 114 181 280 325

Comments

Based on calculation using the RIGES model. Sustained growth scenario Dematerialization scenario. Ranges reflect the outcomes of three scenarios. A scenario in which fossil fuels are phased out during the 21 '* century. Intensive bioenergy system development was assumed.

FAO's Forestry Department established a Wood Energy Information System (WEIS) which collected existing data through the implementation of Regional Studies (WETT, 1997). These regional studies provided a detailed analysis of existing information available in FAOSTAT (1998) and other important wood energy databases, such as UN-Energy Statistics RWEDP and EUROSTAT, The information and data collected and compiled was organized according to the new set of adopted terminology and definitions prepared by FAO (1997a). They contribute to a better understanding of the role of different fuelwood sources, the classification of fuelwood by categories and a clearer definition of the major users of rural and urban areas. Fuelwood consumption in the main regions of the world, divided between developed and developing countries (Table 6.3), includes data from 147 countries arranged according to the FAO classification already used in other documents such as the State of the World's Forests (FAO, 1997b). The total production of wood in 1995 reached approximately 3,900 million m^ out of which 2300 million m^ (Table 6.3) was used for fuelwood. This means that approximately 60% of the world's total wood removals from both forests and non-forest lands were used for energy purposes. In global terms, fuelwood produced either directly or indirectly from forest resources consists of almost 60% of the total forest removals. In other words, energy is the main application of forest products on a volume basis (though much lower in terms of revenue for the forest owners). Only 30% of the woody biomass produced in developed countries is used for energy (33% in Europe and 29%o in North America), whereas in developing countries the amount reaches 80%) on average. In Africa, Asia and Latin America a high proportion of the total wood consumption is used for fuelwood accounting for 35%, 12% and 12% of their respective total energy consumption in 1995.

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Table 6.3 : Fuelwood consumption by global regions during 1995 Ratio: fuelwood/ total energy

Ratio fuelwood/all wood uses

17,600 13,700 3,900

0.15 0.26 0.06

0.80 0.84 0.65

486,248 464,077 22,171

4,800 4,600 200

0.35 0.75 0.03

0.89 0.91 0.53

1,002,846 654,221 348,625

10,000 6,500 3,500

0.12 0.23

0.07

0.81 0.85 0.70

5,804

100

0.52

0.56

Latin America and Caribbean tropical non-tropical

268,364 244,338 24,027

2,700 2,500 200

0.12 0.13 0.07

0.66 0.69 0.48

Developed countries total

536,754

5,300

0.02

0.31

Europe, Israel, Turkey

194,652

1,900

0.03

0.33

42,585

400

0.01

0.27

272,438

2,700

0.03

0.29

27.079

300

0.01

0.36

Total fuelwood demand

Region

m^ X 10 ^

PJ

1,763,263 1,368,440 394,823

tropical non-tropical

tropical non-tropical

Developing countries total tropical non-tropical Africa

Asia

Oceania Tropical

Former USSR Canada and USA Australia, New Zealand, Japan

1

1

0J9 007 22,900 2,300,017 Source: FAOSTAT (1998), United Nations Energy Yearbook (1997) and Wood Energy Today for Tomorrow studies ( FAO, 1997).

1 World

Since 1950 the volume of wood used for energy purposes has trebled following an average growth of 2% per annum. In industrialised countries up to the mid 1970s it had declined, but from then on it was reversed with the energy price shift following the 1970 oil shocks. There has since been some growth, particularly when residue recovery and waste recycling for energy use are taken into account. In the developing world ftielwood has remained the mainstay of energy supply contributing 17,600 PJ in 1995 or 15% of primary energy supply. It contributed 7% of global primary energy supply with 76% used in developing countries. The use in developed countries was approximately 5300 PJ/year but represented only 2% of their total primary energy consumption. (Biomass sources other than fuelwood are not included in this data). Overall the biomass share is by far the largest source of renewable energy, providing more than twice the contribution of hydro electricity worldwide in the form of heat and power. World production of fuelwood for energy use in 1996 was estimated to be about 1.9 billion m^ or 1.4 billion tonnes (FAOSTAT, 1998). In addition an estimated amount equivalent to

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some 0.3 billion tonnes of waste wood was recovered and recycled for energy use. This 1.7 billion tonnes of fuelwood consumption is equivalent to 550 million tonnes of oil. 6.4

Contribution of Fuelwood Types

The perception that fuelwood continually being removed from native forests for firewood and charcoal is the main cause of deforestation is debatable. As discussed in Chapter 5 an important contribution is by non-forest sources, such as trees and shrubs growing on farm lands, irrigation canals, roadsides and marginal lands. The share of fuelwood types derived directly and indirectly from forests, as well as from non-forest land varies with region (Table 6.4). Since it is difficult to assess the volume of wood process residues used for energy, some figures recorded as "fuelwood" also tend to incorporate them. The data confirms the relative importance of fuelwood demand, especially in developing countries. The generation of heat and power from recovered black liquor during the pulping process is also significant, especially in North America and Europe. Here large pulp and paper industries have heat and power cogeneration plants partly fuelled with this form of biomass as well as with bark and other residues. Almost all of a plant's energy needs can be met when black liquor and wood process residues are used. Sometimes surplus power can be sold to the public grid. In the European Union most woody biomass is still used by households for domestic heating either individually or through district heating schemes and this can represent up to 60% of the total wood energy consumed. The technology transfer to developing countries of experience from building and operating modem and efficient bioenergy conversion technologies employed in biomass-fired cogeneration plants in developed countries will be encouraged by the Clean Development Mechanism of the Kyoto Protocol. Table 6.4 : Share of selected fuelwood types of the total wood energy use by region

Region

Traditional fuelwood

Fuelwood types (m*^ x lO'^J Char Wood process residues 15 131

Black liquor

Developing countries total

1,533

Africa Asia Oceania Latin America and Caribbean

445 859 6 223

72 25 0 34

2 10 0 3

3 12 0 19

Developed countries total

187

7

43

228

Europe, Israel, Turkey Former USSR Canada and USA Australia, New Zealand, Japan

56 32 96 3

2 1 4 0

33 3 I 6

51 8 146 23

1,720

138

58

262

World Source: FAOSTAT, 1998

34

Biomass

6.4.1

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Land use

Competition for land availability with food and fibre production is a major concern for near term biomass production for energy. This includes using existing products for energy purposes where the market encourages their collection or diversion from other uses. It also involves the growing of specialist energy crops on arable or pasture land. Forests The world's forests are estimated to be 3.4 billion ha covering about 27% of the land area and containing about 440 billion dry tonnes of woody biomass. In addition, some 1.7 billion ha of other land have some tree or woody vegetation cover. The total energy stock contained in the forests and other woody vegetation is equivalent to some 215 billion tonnes of oil. The forests in industrialized countries provide a quarter of this stock and are stable, though with a slight tendency to increasing stocks over time. In developing countries however there is an annual loss of forest due mainly to the conversion of forest land to other uses. Deforestation amounts to about 12 million ha per year or 0.6% of forest area (FAO, 1997b). The annual use of wood for energy represents about 0.3% of the total stock, a rate of use well within the natural growth of forests but is not evenly distributed in relation to the stock. The consumption in Brazil, for example, represents 0.3% of its stock, while the consumption in India represents 2.5% of its stock, which is the highest in the world. Agriculture Arable land occupied 860 Mha in 1982 and 1,477 Mha in 1989. At the same time, forest land decreased from 5,200 Mha in 1982, to 4,087 Mha in 1989, to 3400 Mha in 1993. In view of the large improvements in productivity levels of agricultural land in the past three decades, farmers in USA and Europe are offered financial packages to leave a portion of their land fallow. These crop lands are already being taken out of intensive farming under the "SetAside Scheme" of the European Community and the "Crop Land Reduction Scheme" of the USA. It is estimated that in the United States, about 30 Mha had been removed from crop production by 1988. In the European Community (12 countries) surplus agricultural land resulting from rising yields and changing agricultural subsidies reached 15-20 Mha by the year 2000, and may reach at least 40 Mha this century if productivities continue to increase. The production of agricultural surpluses in Europe and North America resulting from large subsidies has attracted more subsidies to lower the production. As clearly outlined by the late Prof. David Hall (Hall & Scarse, 1998) this land represents a significant opportunity to initiate biomass energy production schemes for developed countries, especially if coupled with the use of agricultural and forestry residues. Waste lands Estimates of degraded and abandoned land generally lie between 700 and 1,000 Mha which is equivalent to about half the world's present arable land (WEC, 1999). The extent of this available land has led scientists to highlight its potential for use in mitigating the greenhouse effect by managing it to become a carbon sink. Wastelands are regarded as having good potential for storing carbon in trees due to the relatively low levels of carbon in their soils and poor levels of vegetation particularly in arid lands in developing countries. Both soil and vegetative carbon stocks would increase under afforestation programmes.

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Environment

The biomass productivity values of plantation forests have been reported to be up to 40 ovendry tonnes per hectare per year (odtylia/yr) for high intensity plantation where sufficient water and fertile soils are available. However, continuous production on a sustainable basis at 1015 odt/ha/yr may be more satisfactory for the long term. Experts however, have suggested that countries like India should plan their long-term policy for biomass plantations on producing an average yield level of only 4 odt/ha/yr (FAO, 1995). 6.4.2

Projection of land use

To address the issue of possible land-use conflict between biomass and agriculture the World Energy Council used IIASA's Basic Linked System (BLS) of agricultural models to calculate the food and agricultural land requirements. The required expansion of agricultural cropland to increase food supply and to provide for an additional five billion people in 2050, was estimated to be 250 million ha, with 200 million of these additional ha required in developing countries. This compares with the 1,440 million ha used by agriculture in 1990. The land area required for energy crop production in the "high-growth case" scenario was estimated at 400 to 600 million ha by 2050 and 700 to 1,350 million ha by 2100. In an "optimistic" scenario with a similar biomass demand but a lower land requirement, biomass productivity was assumed to be possible at 20 odt/ha/yr, with two-thirds of the demand being met from dedicated energy plantations and the remainder being recovered from agricultural and forest residues. These additional land areas for both agriculture and biomass would be available in principle (Table 6.5), but they stretch future land requirements and land-use changes to their ultimate limits. By 2100, agriculture (1,700 million ha) and biomass (690 to 1,350 million ha) together could require over 3,000 million ha - being as much land as is currently covered by forests. Land-use conflicts may then become a major constraint. Note that the potential productivity increase from genetically engineered crops of the future is not included in this analysis. Table 6.5: Land use in 2050 and 2100 compared with 1990, for selected world regions (million ha) Additional land use

Current use

Industrialised countries'^ Africa Asia Latin America Developing countries total World

Potential arable land"

Biomass" (2050)

Biomass (2100)

670

Agriculture (2050) 50

70-100

150-350

700 880 590

150 470 150

95 33 72

110-180 160-250 50-80

140-340 260-340 140-320

990 500 950

2,120

2,170

770

200

320-510

540-1,000

2,440

3,890

3,360

1,440

250

390-610

690-1,350

-

Forests

Pastures

Agriculture

1,770

1,190

630 600 890

•

For maximum biomass scenarios the range corresponds to 8 to 10 odt/ha land productivity by 2050 and to 12 to 10 odt/ha by 2100. Lower bounds also assumed that 80% (2050) and 67% (2100) of biomass will be produced in plantations. Higher bounds assumed 100% plantation biomass. FAO (UN Food and Agriculture Organization) estimate. Includes OECD, EU and Economies in Transition.

Bioniass

6.5

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Advanced Conversion Processes

Technically advanced commercial or industrial conversion processes involving the use of biomass energy are currently in operation or under development in many parts of the world. Conversion technologies such as gasification, cogeneration, co-firing and pyrolysis systems have undergone significant technical improvements. WEC's World Resources Handbook, (1998) classified the technological conversion processes into three main categories : i) combustion/gasification; ii) thermo- chemical; and iii) biochemical: These have been covered earlier in Chapters 3 and 4, but are included again here w^ith emphasis on small-scale installations and their suitability for rural areas of developing countries. The well-proven technologies could be ideal candidates for projects developed in developing countries under the Clean Development Mechanism. 6.5.1

Combustion/Gasification

Combined heat and power cogeneration plant Benefits of combined heat and power (CHP) production or "cogeneration" can be summarised as follows. i) Cogeneration plants can achieve a total efficiency of 80-90%, while in conventional condensing turbine power plants where waste heat is not utilized, the efficiency remains around 30 - 40%. ii) High efficiency levels, and thereby low emissions, make conversion plants more environmentally friendly, iii) Cogeneration plants (combined heat and power, CHP) have a high level of availability since they are simple and reliable, enabling uninterrupted energy production. At the same time, they can be highly automated, thereby minimising the staffing needed and reducing the cost of operation and maintenance activities, iv) Investments in a CHP plant can enhance the competitiveness of local firms by providing employment to local fuel providers and other services in the nearby areas, v) CHP is a more environmentally attractive proposition than building separate heat and power plants, vi) Primary energy consumption in cogeneration, compared to corresponding generation in separate processes, is lowered by approximately one-third. The decrease in fuel consumption reduces the burden of energy production on the environment since, for fossil fuel plants, carbon dioxide emissions are also reduced. The first industrial cogeneration plant was built in Finland in the late 1920s, and the first district heating plant was buih in the 1950s (Faaij, et aL, 1997). The 'aim' was to increase the economy and reliability of power production, often using local energy sources. In many developing countries with a sugarcane industry, bagasse, a by-product, also has good potential in cogeneration plants. Industrial back-pressure power production is mainly based on waste black liquors originating from pulp production and containing organic wood residues. The production of pulp for the

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manufacture of paper started in Finland as early as the 1880s and 85% of the Finnish industrial cogeneration plants are connected to the forest processing industry which consumes about one-quarter of all energy used in Finland, or 60% of the total energy consumed by industry. Co-firing ofbiomass in pulverised coal-fired boilers. Co-firing of biomass with coal or natural gas is a safe route for conversion of many organic wastes into energy. The Netherlands, for example, has eight organic, MSW (municipal solid waste-to-energy) waste co-firing projects in use or tested since 1995, the displacement of coal for each amounting to 3-5%. Four of the projects are in commercial operation and the others have undergone demonstration tests. The co-combustion power plant at Gelderland has been in operation since 1995, built to a capacity of 602 MWg. The biomass fuel is waste wood originating from demolition activities. It is milled and fired separately from the coal. Approximately 60,000 tonnes per year of waste and demolition wood is used annually, meaning about 3% of coal displacement. If disposed of in landfills it would require a large volume and on decay would produce methane and other greenhouse gases. As an energy source used in a coal-fired power plant, it reduces the consumption of fossil fuel and thereby reduces the greenhouse gas emissions. Additional benefits are a reduction of the ash volume, sulphur dioxide and nitrous oxide emissions. The electrical output based on the wood powder component of the fuel is approximately 20 MWe which replaces 45,000 tonnes/yr of coal and approximately 110,000 tonnes/yr of carbon dioxide is avoided. There is also a yearly reduction of 4,000 tonnes of fly ash since the ash content of wood can be ten times less than that of coal (Beekes et«/., 1998). Co-combustion also provides an opportunity to convert sewage sludge into an energy product after converting the waste into pellets. BioMass Nederland began the production of pellets consisting of garden prunings, sewage sludge and paper sludge in early 1998. It now produces around 150,000 tonnes/yr of material with a higher heating value of about 16 GJ/t which could displace 30,000 tonnes of coal (Beekes, et al., 1998). Production of the pellets is simple. The comminuted waste products are combined in a mixer and from this pellets are produced under pressure without the necessity for a drying step. The pellets have a moisture content of about 40% and can be co-fired with coal or used alone. A blend of coal and pellets can be pulverised using the existing coal hammer mill of the power plant. This process could have useful application in developing countries when investment capital is provided, possibly by countries investing in the Clean Development Mechanism. The pellets would be made from a variety ofbiomass materials and used in small scale conversion systems. Gasification Biomass integrated gasification combined cycle (BIGCC) systems combine flexible ftiel characteristics and high electrical efficiency (section 4.2). Electrical conversion efficiencies of 40 percent (LHV) are possible at a scale of about 30 MWe (Consonni & Larson, 1994; Faaij et al., 1997). Demonstration projects are under way in various countries and for various gasification concepts. The first generation of BIGCC systems have relatively high unit capital costs which, depending on scale, are $2,800 - $5,000/kW. Future cost reduction

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potential is considerable with capital costs down to $1,100 - 2,000/kWe by 2020 (Williams & Larson, 1996; Faaij, et al, 1998). Small (fixed bed) gasifiers coupled to converted diesel or gasoline engines (typically for systems of 100-200 kWg with an approximate electrical efficiency of 15 - 25%) are commercially available on the market (Gigler, et ai, 2001). High costs and the need for gas cleaning and careful operation have constrained large numbers of potential applications though several systems are being applied successfully in rural India, Indonesia and China (Stassen, 1995). China is paying increasing attention to the modernization of biomass and significant efforts are being made to develop and upgrade biomass technologies, particularly gasification, densified biomass, and biogas at the small- to medium-scale up to around 30 MW. Their gasification technologies comprise movable and fixed beds and small domestic stoves. By 2010 it is estimated that Chinese power generation capacity using straw, sawdust and bagasse will reach 300 MWg. Already various circulating fluidized-bed gasifier plants operate using biomass waste. India decentralized its electricity generation programme in 1995 and provided support for a total of 10 to 15 MWe of small-scale projects designed to promote energy self-sufficiency in small communities. Over 500 MWe of biomass power capacity was projected in the 19972002 Plan. By the end of 2000 there were over 2,000 operational gasifier systems with a total capacity of 35 MWe, mostly used in village electrification. Various studies have put the potential of cogeneration from bagasse at between 2,800 and 5,100 MWg. In view of this potential the Ministry of Non-Conventional Energy Sources (MNES) in 1994 launched the national programme on bagasse-based cogeneration. At that time only three sugar mills had an export surplus capacity of 5 MWg. This rose to 16 mills late in 1997 with a capacity of 56 MWe and by the end of 2000 a capacity of 272 MWg had been commissioned with a further 373 MWe under installation. Cuba, Mauritius, Thailand and elsewhere are following suit. 6.5.2. Char production Carbonization of wood to produce char is practiced in many countries, both for domestic and industrial uses (section 4.3.1). Many cottage industries in developing countries use char for energy and in Brazil, the world's largest char producer and consumer, it is used in heavy industries such as pig-iron, steel making, cement etc. Char making technology has remained unchanged in many ways because the industries involved do not have the technical or economic capacity to invest in R&D. Brazil is the only country where there has been an RifeD programme of any significance. As a result its char technology process has efficiencies of about 30 to 35% compared with 12 to 25% in many other countries. Thailand has a well-developed char making industry and substantial efficiency improvements have also been reported. The benefits of char versus woody biomass include ease of transport and having a consistent quality fuel. However much of the stored energy is lost in the volatile gases driven off during production.

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Bioenergy Options for a Cleaner Environment

Biochemical energy conversion processes

Advances made in these conversion processes, have opened up many new possibilities, as outlined in chapter 4. Three main areas of interest for developing countries are: i) bioethanol from sugarcane and com, but with the most promising area of research being the production of ethanol from cellulosic material via hydrolysis; ii) biodiesel from vegetable oil crops; and iii) biogas production from animal and organic wet wastes. Worldwide interest in liquid biofuels for transportation increased considerably in the 1970s and 1980s owing to high oil prices. In the 1990s this interest subsided as the crude oil price declined. However, in industrial countries interest in liquid biofuels has gained renewed interest stemming from environmental, pollution, agricultural and social considerations. There are advantages for developing countries from technology transfer and many successful programmes already exist. Bioethanolfuel Brazil and USA have pioneered large-scale ethanol fuel programs and on a smaller scale various other sugar cane-producing countries have been involved, such as Argentina (220 Mt/year), Zimbabwe (40 Mt/year), Kenya (15 to 16 Mt/year), and Malawi (6 Mt/year). In Europe, trials of bioethanol have been carried out in Germany, Italy and Sweden and a small amount is already blended at around 4% with gasoline in France. Brazil's alcohol program (the world's largest) was set up in 1975 and is currently replacing about 250 000 barrels/day of imported oil. At its peak (late 1980s) almost five million automobiles ran on pure bioethanol and a further nine million ran on a 20 to 22% blend of alcohol with gasoline. From late in the 1980s the combination of high demand for ethanol, higher prices for sugar and uncertain government policies resulted in a shortage of ethanol. As a result the fraction of new dedicated ethanol cars dropped to 51% in 1989, and to almost zero in 1997. From 1976 over 140 million m^ of gasoline equivalent has been replaced by ethanol and the estimated foreign exchange savings have been put at about US$50 billion (IPCC,2001). The USA is the world's second largest fuel ethanol producer (section 4.4). In 1994 production was about 5.3 billion litres, and a further 908 million litres of new annual capacity was reported to be under construction. Further expansion occured as ethanol entered into the octane market in the form of ethyl tertiary butyl ether (ETBE) and as a "neat" fnel. Ethanol is now produced in 21 States, and a gasoline blend (gasohol) represents 10% of the USA's fuel sales, being used by over 100 million motorists. By 2005, it is estimated some five million American vehicles will be running on non-petroleum fuels. The US Department of Energy (DOE) aims to produce ethanol from wood at a cost of US$0.20/litre in 2005 and US$0.14/litre in 2030 (Woods, 1999). The DOE has a goal of producing about 9 billion litres of ethanol via enzymatic hydrolysis in 2005 and as much as 85 billion litres by 2030. Biodiesel Four main technical alternatives are being investigated for both vehicle use as well as in diesel generating sets used in rural areas when locally produced fuel could be used.

Biomass

i) ii) iii) iv)

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vegetable oil mixed with diesel for heating, purified vegetable oil for special diesel engine designs, trans-esterified vegetable oils for standard diesel engines, and trans-esterified vegetable oils mixed with diesel for standard diesel engines.

Biodiesel is a fuel with properties similar to conventional diesel oil which enables it to be used in conventional diesel engines at any proportion without modifications (section 4.5). It can be produced from any oil-bearing crops such as rapeseed, soyabean, jatropha curcus, palm oil, coconut or from animal fats. Rape methyl ester (RME) produced from oil-seed rape is the main source in Europe and Canada, while soya oil is used in the USA. Biodiesel is commercially available in several countries but normally only competes on price with mineral diesel where significant government support is provided. An advantage of biodiesel is that there is considerable experience with growing oilseed crops for food and virtually the same agricultural practices can be applied. Large-scale commercial production of biodiesel from rapeseed is possible in plants up to 60,000 t/y capacity. In the USA, the National Biodiesel Board was created in order to commercialize biodiesel. Particular emphasis is being placed on the 20% biodiesel/conventional diesel blend (B20) for use in niche markets in marine areas, city bus fleets, and the mining industry. Despite increasing interest, the biodiesel market in industrialised countries will remain small and localized because of high costs and the high demand for edible oils. In remote rural areas of some developing countries where there is a high production potential, biodiesel could meet local demands where all available land is not needed for food and fibre production to sustain ever increasing populations. In the short term, biodiesel will probably be confined to OECD countries that, for environmental, agricultural and other reasons, can afford to pay high subsidies. Certain developing countries such as Malaysia and the Philippines have an interest in producing biodiesel from surplus palm oil and coconut oil. Tallow surpluses are a further option in meat processing countries (Sims, 1995) and being a by-product, are cheaper and can better compete with diesel. Anaerobic digestion Anaerobic digestion of biomass to produce biogas has been applied commercially with success in many situations and for a variety of feedstocks such as organic domestic waste, organic industrial wastes, manure, and sludges (section 4.1). Large advanced conversion systems have been developed for industrial waste streams and applied in many countries. In India and elsewhere there is widespread production of small-scale biogas using animal and other wastes to produce biogas for cooking, lighting, and power generation as a result of a major development programmes. Installation of 12 million family size biogas plants based on cow dung alone is anticipated but only 3 million plants had been installed up to March 31, 2000. Anaerobic digestion and gas engine driven generators have a low overall electric conversion efficiency (roughly 10-15%, depending on the feedstock) but is particularly suited for wet biomass materials. Landfills are natural anaerobic digestors of rubbish and contribute to atmospheric methane emissions resulting from bacterial action on the organic waste products. In many situations the collection of landfill gas and its conversion to electricity using gas engines is profitable, and such systems are becoming more widespread (Faaij, 1998).

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Bioenergy Options for a Cleaner Environment

Environmental and Social Issues

Biomass, being renewable, has a positive impact on the environment during its production cycle. However, during the conversion process to bioenergy, it can produce certain harmful emissions. The main positive environmental impact is the fact that it is basically carbon dioxide neutral, assuming the rate of harvest and use equals the rate of re-growth of the trees or replanted crops. The emissions from wood energy systems normally depend on the type and scale of a system and its operation. In general, smaller scale projects have the advantage that they require less distance to cart the material, and therefore produce less transport-related emissions. However, conversion related emissions become lower per unit of energy produced when the scale of conversion unit increases. The harmful emissions associated with biomass that can occur include carbon monoxide, polycyclo - aromatic - carbons (PACs), hydrocarbons (HC), nitrous oxides (NOx), dioxins, ozone and particulates. PACs and carbon monoxide occur as a result of incomplete combustion and will therefore improve with the efficiency of the conversion unit. Thermal efficiencies in well designed small scale household wood heaters can be around 50% (lower heating value), but are much lower in less efficient designs. Modem district heating stations in Denmark have efficiencies near 90% (lower heating value), which lead to much lower CO and PAC emissions. The situation in the Netherlands illustrates the CO emission problem of household wood heating systems. Although residential wood heating accounts for only about 0.5% of the national primary energy consumption, it is responsible for 10% of the total Dutch CO emissions. This problem may be overcome by improvement of wood heating system designs or centralisation of the conversion plant as district heating, which will in general raise conversion efficiencies and enable emissions to be better controlled. Traditionally in developing countries biomass use has often been associated with environmental degradation from deforestation and health hazards. These are complex and inter-related socio-economic and cultural issues. Deforestation concerns were particularly prevalent in the 1960s when the premise was that it was occurring as a consequence of overcutting of forests for fuelwood. In fact over-cutting was usually a secondary consequence of a more general failure to care for diminishing forest lands and resources. Evidence shows that much of the fuelwood and charcoal was not obtained from forests but from scattered trees in the vicinity (section 5.3.2). A large number of more recent studies have shown that biomass can have many environmental benefits if produced and used sustainably (Sims, 2003). This is a view more widely accepted nowadays but the main problem is the continued inefficient use of biomass in developing countries at the domestic scale. The use of modem biomass as an energy carrier provides a number of strategies which can be used to tackle greenhouse gas emissions: i) sustainable production and use of an energy resource which results in CO2 neutral emissions; ii) sequestration of CO2 through forest crops which create carbon sinks when first planted to increase the carbon stocks; and

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iii) direct substitution of fossil fuels, with the corresponding carbon offset value and environmental and ecological benefits. Automobiles generate atmospheric pollution and contribute very significantly to the emissions of greenhouse gases (notably CO2), while being the fastest growing energy consumption sector worldwide. Each year the transportation sector produces 1,800 million tonnes of carbon equivalent emissions (MtCe), or 30% of world carbon emissions. By 2010, due mainly to increasing demand in developing countries, the current fleet of 550 million cars may have increased to 1.1 billion and CO2 emissions will have risen by 65% over the 1990 level, owing to the increased use of oil-derived liquid fuels. The rapid growth of the transport sector will have major environmental implications (IPCC, 2001). Use of alternative environmentally-sustainable transportation fuels such as bioethanol and biodiesel offers good potential for reducing emissions although the volumes involved are daunting to meet the growing demand. In Brazil, the large-scale use of ethanol fuel has played a significant role in reducing the level of pollution. For example, the introduction of ethanol-gasoline blends had an immediate impact on the air quality in the large cities, particularly Sao Paulo. Lead additives were gradually reduced as the amount of alcohol in the gasoline was increased and were finally eliminated in 1991. The aromatic PACs, which are particularly toxic, were also eliminated and many other pollutants were also significantly reduced. Various studies in other countries have looked at the potential of reducing pollution through the use of cellulose-based ethanol, which offers the potential of reducing carbon emissions from vehicles by 80 to 95%. It was estimated that the use of 150 billion litres of cellulose ethanol in the USA would reduce carbon emissions by 100 MtCe, and total greenhouse gas emissions by 930 MtCe. 6.6.1

Energy plantations and carbon sequestration

Sustainably grown biomass is virtually carbon dioxide neutral when used for energy, depending on the production and conversion methods employed. If energy crop production is to be regarded as a carbon sink, the total amount of carbon stocks stored per hectare on average between harvests and regrowth in the bioenergy crop must be greater than the average level of stored C in the vegetation previously on that land. When the biomass is used as a substitute for fossil fuels, it can be regarded as a carbon offset in terms of the avoided carbon dioxide emission that would otherwise have been derived from using fossil fuels. The most clear benefit in carbon sequestration terms would be if the plantation was somehow established in a desert with an existing standing stock of virtually zero tC/ha. Then both the above and below-ground carbon levels would be increased significantly over time as the plantation matured. Conversely, on fertile land, if the standing stock of the previous vegetation was greater than that of a newly established plantation, then a net reduction in the carbon stock level per hectare would result. If the plantation biomass was to be used as a fossil fuel substitute (or maintained as a long-lived wood product), a reduction of atmospheric carbon dioxide emissions would result. The greater the level of vegetation on the land prior to the energy plantation being established, then the longer it would take for fuel substitution benefits to reduce the amount of carbon dioxide initially released from land clearing. This results from the relatively large amounts of carbon dioxide which are released following the initial land clearance and then through use of fossil fuels during harvesting and transport

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operations. The key point here is that biomass used for energy purposes should never involve the deforestation of indigenous forests. Indeed, in developing countries, the establishment of energy plantations on available land already free of forest vegetation, can provide fuelw^ood for local use, assist development of local industries and serve to protect from further deforestation activities. The three most important factors in assessing whether biomass energy plantations are effective carbon sinks are: (i) carbon inventory of the natural vegetation; (ii) productivity of the plantation; and (iii) the time perspective adopted. The use of biomass from energy plantations and energy crops provides an opportunity to avoid fossil-fuel-derived carbon dioxide emissions. However, the present intensive agricultural methods for commercial production of biomass must become sustainable and any residual product should also be used. The calculation of carbon-flows and energy 'output: output' ratios to monitor net carbon dioxide production must be integral to the strategies for energy provision. It would require large quantities of inputs in the form of management, fertilizers, pesticides, irrigation and labour in order to raise the productivity of biomass significantly, but this would not be sustainable. Perhaps genetically engineered crops in the future, once proven to be environmentally safe, will be able to raise current productivities significantly. Assuming good biomass productivities of around 12 oven dry tonnes/ha/yr (6tC/ha/yr), reforestation of available land could theoretically remove about 5 GtC from the atmosphere per year over the next 40 years. For comparison the 1998 global emissions of carbon dioxide into the atmosphere were around 7-8 GtC of which 3-4 GtC appeared as an atmospheric increase in CO2 levels. Biological sequestration programmes can, therefore, only be regarded as a temporary measure, buying time until other sustainable forms of energy or permanent physical carbon dioxide removal systems can be developed. 6.6.2

Relevance to economics and employment

The FAO's Regional Wood Energy Development Programme (RWEDP, 1996), estimated that the net effect of fuelwood use in member-countries in 1994 implied a saving of about 278 Mt carbon dioxide which otherwise would have been emitted into the global atmosphere from fossil fuels. If coal was to be replaced by the fuelwood, then the carbon dioxide avoided would be over 600 Mt by 2010. These figures can be translated into costs avoided for recapturing the carbon dioxide which would total US$17.5 billion saved by fuelwood use in 2010. At the country level, the share of fuelwoods within total wood consumption ranged from a low of 22% in Malaysia (which is in line with European countries) to 98% in countries such as Bangladesh, Cambodia, Nepal and Pakistan. Germany is also an important wood energy consumer with 184 PJ but this is only a meagre 1.2% of the national consumer energy demand.

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The value of fuelwood consumed in the 16 Asian Member Countries of the RWEDP has been estimated, using average calorific values and market prices for fuelwood and char, to be the equivalent of US$29 billion/year. In Thailand, in a comparative analysis, fuelwood contributed to 30% of the total energy supply with a value of approximately US$2 billion, which was more than 50% of the total energy import bill for 1994. A similar evaluation covering 15 European countries provided an indication that wood energy use was worth approximately €4 billion per year. Fuelwood use generates at least 20 times more local employment than energy from oil products (on a per unit of energy basis). Hence, national interests like balanced growth, employment and equity are linked to energy supply policies (Table 6.5). In countries seeking additional employment and where income is relatively low, this can be advantageous. Where labour is expensive or in short supply (especially for undertaking manual work activities), high labour demand can be a disadvantage. Table 6.5: Estimated employment per fuel type employed (in 1993) Fuel type

Kerosene LPG Coal Electricity wood-fired Fuelwood Charcoal

6.6.3

Amount of fuel/TJ

Estimated employment/TJ energy consumed (in person days)

29 kilo litre 22 tonnes 43 tonnes 228 MWh 62 tonnes 33 tonnes

10 10-20 20-40 80-110 110-170 200-350

Future opportunities

•

Biomass will continue to play an important role in meeting the energy needs of the 2 billion people currently without access to electricity or commercial forms of energy.

•

Land for biomass production will not be a bottleneck. The World Energy Council projected that even if 400-700 million hectares of land were to be used for biomass energy production halfway into the 21^^ century, land for food and fibre production will still be available using present day agricultural production technologies.

•

Perennial crops can offer relatively cheap and productive biomass, with low or even positive environmental impacts.

•

Genetic improvement and optimized production systems, multi-products from biomass, and multi-functional land use, could bring biomass closer to the competitive costs of fossil fuels.

•

Modern bioenergy production can play an important role in rural development in both developed and developing countries.

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•

6.7

Flexible energy systems combining biomass and fossil fuels are likely to become popular environmentally friendly, low-risk, low-cost energy supply systems in the short term. •

Emerging technologies for the efficient conversion of biomass will allow commercial liquid and gaseous biofiiels or heat and electricity to compete with fossil fuels. The wide local biomass resource availability makes it suitable for providing income to rural poor and developing rural areas.

•

Biomass has the potential to become a more important source of energy both in developed as well as developing countries, as a means of mitigating for climatic change. Conclusion

Biomass is an abundant source of energy that can be collected and converted via many routes to provide useful energy services. Modem biomass technologies are well proven in developed countries and many successful bioenergy plants have also been operating in developing countries. There is good potential for biomass to provide energy services to the third of the world's population currently without electricity, transport, etc. However to be successful, the biomass has to be produced sustainably and used in an environmentally clean manner.

REFERENCES Beekes, M.L. et aL, 1998. Co-combustion of biomass in pulverised coal-fired boilers in the Netherlands. Proc. 17^*^ World Energy Council Congress, vol. 3 (Paper 3.2.04). Houston, USA. September. Consonni, S. & Larson, E.D., 1994. Biomass gasifier aeroderivative gas turbine combined cycles. Proc. "Cogen Turbo Power, 1994". American Society of Mechanical Engineers, New York. Faaij, A., 1998. Optimization of the final waste treatment system in Netherlands. Resources, Conservation and Recycling 22 : 47-82. Faaij, A. et aL, 1997. Gasification of biomass wastes and residues for electricity production. Biomass and Bioenergy 12(6): 387 - 407. Faaij, A., Meulman, B. & van Ree, R., 1998, Long term perspectives of BIG CC technology, performance and costs. Utrecht University, Department of Science, Technology and Society, and Netherlands Energy Research Foundation, Petten, Netherlands. FAO, 1995. Forests, fuels and the future. Forestry Topics Report No.5. United Nations Food and Agricultural Organisation. Rome. FAO, 1997a. Unified wood energy terminology. United Nations Food and Agricultural Organisation, Rome.

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FAO, 1997b. State of the World's forests. Forestry Department. United Nations Food and Agricultural Organisation, Rome. Gigler, J., Sims, R.E.H. & Adams T.A., 2001. Small scale, biomass-fired electricity production systems -present and future. Report, Massey University, Palmerston North, New Zealand. FAOSTAT, 1998. United Nations Food and Agricultural Organisation, Rome. Hall, D.O. & Scrase T.I., 1998. Will biomass be the environmental fuel of the future? Biomass and Bioenergy 15, 357-367. IPCC, 2001. Third Assessment Report - Mitigation. Inter-Governmental Panel on Climate Change, Cambridge Press, www.ipcc.ch Leach, T. & Go wen, A., 1987. Household Energy Handbook: an interim guide and reference manual. World Bank, New York. RWEDP, 1996. Regional wood energy development programme for Asia and Pacific. Report. United Nations Food and Agricultural Organisation. Rome. Sims, R.E.H., 1995. The biodiesel research programme of New Zealand. Proc. 2" Biomass Conference of the Americas, Oregon. 849 -858. Published by N.R.E.L., Golden, Colorado. Sims, R.E.H., 2003. The triple bottom line benefits of bioenergy for the community. OECD workshop "Biomass and Agriculture", Vienna, June. Organisation for Economic Cooperation and Development, Paris, www.oecd.org Stassen, H.E., 1995. Small scale biomass gasification for heat and power production : a global review. World Bank Technical Paper 296, Energy Series. Washington, D.C. WEC, 1999. Conclusions and recommendations of the 17^*^ World Energy Council Congress, Houston USA. Held in September 1998. WEC, 1998. Survey of energy resources. World Energy Council. WETT, 1997. The role of wood energy in Europe and OECD. Wood Energy Today for Tomorrow. Forestry Department, FAO, Rome. Williams, R.H. & Larson, E. D., 1996. Biomass gasifier gas turbine power generating technology. Biomass and Bioenergy 10 (2-3): 149-66. World Energy Assessment, 2000. UNDP/UNDESA/World Energy Council.