Forest energy plantations: an international perspective

Geoforum, Vol. 16, No. 3, pp. 257-x4,1985 Printed in Great Britain.

MM-7185185 $3.00 + 0.00 Pergamon Press Ltd.

Forest Energy Plantations: an International Perspective*

C. COCKLIN,1_ S. C. LONERGANt

and D. W. CLARKE,t

Hamilton, Ontario, Canada

Abstract: Recognition

of the limits to fossil fuel reserves and dramatic increases in the prices of many conventional fuel sources have promoted an interest in renewable energy resources. Biomass from forest plantations is recognized as one alternative with potential in many countries. This paper describes the general characteristics of forest energy plantations. The results of an extensive survey of forest energy development projects throughout the world are presented, therein providing an international perspective on the status of energy plantations. The potential contribution of forest energy projects in the developing nations is examined in greater detail.

Introduction

the results of an extensive international survey of forest energy projects are presented. Attention is given to the potential contribution of forest plantations to energy supply, and to the benefits that forest energy projects will impart to the respective participant nations.

Developed nations attained their status as industrial leaders over a period when energy was perceived to be of virtually unlimited supply and was inexpensive relative to other productive inputs (MARTIN and PINTO, 1978). In the early 1970s energy became increasingly expensive and this created severe problems, both for developed nations that had become heavily dependent on imported energy and for developing nations that were attempting to promote economic development, which is closely linked with energy consumption (CLEVELAND et al., 1984).

World Biomass Energy Use

Biomass is defined as unfossilized biological material and in the energy context refers to such products as animal manure, aquatic plants, agricultural crops, forestry residues and trees. It is estimated that solar energy converted through photosynthesis and stored in the form of biomass each year is ten times greater than the world’s energy consumption (ANDERSON and ZSUFFA, 1983; HALL and MOSS, 1983). Total energy stored in biomass, approximately 90% of which is in trees, is estimated to be equivalent to total proven fossil fuel reserves (HALL and MOSS, 1983). Yet the potential of this vast supply of energy remains, for the most part, unrealized, despite the fact that approximately half of the population of the world relies on biomass for its supply of energy and that an estimated one-seventh of the energy consumed globally is already obtained from biomass (HALL et al., 1982).

Responses to the recent energy ‘crises’ include the search for, and development of, renewable energy forms. Numerous alternatives have been explored, including tidal, solar and biomass energy resources. Biomass from plantation forests is a potential source of energy that has attracted considerable attention since the mid-1970s (SZEGO and KEMP, 1973; INMAN and SALO, 1977; LOVE, 1980; ZSUFFA, 1982). The characteristics of forest energy plantations are described in this paper and *Funds for this project were provided by the Social Science and Humanities Research Council of Canada, grant No. 410-83-0515 RI. tDepartment of Geography, McMaster University, Hamilton, Ontario, Canada.

The role of biomass energy in developing nations is particularly significant, providing on average 43% 257

258

of the total energy used and accounting for more than 90% of the energy consumed in some countries (CHAITERJI, 1981; HALL et al., 1982). According to CHATTERJI (1981) in the developing countries 90% of the total population currently relies on wood to provide 90% of the energy utilized. HALL and MOSS (1983) further estimate that in the rural areas of the developing world 1 tonne of wood is consumed per person annually, primarily for domestic cooking and heating, but also to some extent for industry and agriculture. A serious consequence of the extensive use of wood as an energy source is deforestation. This has wide-ranging effects, including the loss of topsoil, erosion, silting of dams and streams, increased flooding and possible climatic changes (HAYES, 1981; MATTHEWS and SIDDIQI, 1981). As local wood resources are depleted, social costs are also incurred in terms of the higher monetary or labour costs of fuelwood collection (HALL and MOSS, 1983). Reforestation is a logical, if only partial, response to the ‘fuelwood crisis’, but in the developing countries replanting schemes are not well developed (HALL and MOSS, 1983). Financial resources are often allocated to nuclear and fossil fuel developments, technologies considered by some to be ill-suited to the needs of people in the Third World (HAYES, 1981). The contribution of biomass to energy supply in the developed nations has declined rapidly since the late 1800s. In North America, for example, fuelwood accounted for almost 90% of energy use during the 187Os, but today less than 5% is derived from biomass (CANADA, HOUSE OF COMMONS, 1981). The consumption of biomass energy in the developed world is estimated to be only 1% of the total (HALL et al., 1982). However, recognition that the various biomass energy alternatives potentially represent a large, domestically available and renewable energy source has led many developed countries to explore what opportunities there are for biomass to contribute substantially once again to national energy supply. Plantation forestry is one source of biomass energy that is regarded as having considerable potential, both for Third World countries and for developed nations (INMAN and SALO, 1977; U.S. DEPARTMENT OF ENERGY, 1978; ANDERet al., 1983). SON et al., 1983; DRYSDALE Perceived advantages of forest energy plantations include the following (SAJDAK et al., 1981; ANDERSON et al., 1983):

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1. They represent a domestic source of energy and thus help maintain security of supply and represent an advancement towards the objective of energy self-sufficiency. 2. Plantations are renewable. 3. Production systems are similar to those of cash crops and provide a rapid return on investment. 4. Production is at a local scale and benefits accrue primarily to the region. 5. The supply system is flexible in that plantations can easily be moved in response to changing spatial demand patterns. 6. Alternative end uses impart versatility to the tree crops. 7. Energy plantations are ecologically inoffensive. 8. Society benefits through the improvement of regional economies and by creating employment opportunities. The concept of forest energy plantations appears to have been first described by SZEGO and KEMP several countries have (1973). Subsequently, become actively engaged in research and development of forest energy schemes.

The Characteristics Energy Plantations

and Feasibility

of Forest

Forest energy plantations are considered to represent a viable alternative in regions where trees and wood residues are not locally available in sufficient quantities to supply energy conversion facilities, but where land is available for the development of energy forests (ANDERSON et al., 1983). The existence of large areas of land not suited to food production but which are capable of supporting wood energy plantations implies that a substantial resource base for biomass production exists in many countries (MORGAN et al., 1983). Energy plantations have been characterized as being comprised of genetically improved, intensively cultivated, closely spaced, broadleaved trees that are harvested repeatedly over cycles of 10 years or less (ANDERSON et al., 1983). The primary concerns in establishing energy plantations relate to the bioecological basis (site, tree species, moisture and nutrient availability), genetic improvement of trees (hybridization and cloning) and cultural pracweed control, tices, namely site preparation, fertilization and irrigation (ANDERSON et al., 1983). The ability of hardwood trees to sprout from coppices leads to reduced replanting requirements and, accordingly, hardwoods are favoured over

GeoforumNolume 16 Number 3/1985 conifers for energy plantations (SAJDAK et al., 1981). In addition, the rapid growth characteristics of the hardwood sprouts generally define these trees as being better suited for energy plantations. SAJDAK et al. (1981) note, however, that due to the site-specific nature of plantations, there are instances where conifers may be more desirable. In comparison with conventional forest plantations, the fast growing energy plantations exhibit several advantages (FRASER el al., 1981). These include higher productivity per unit land area, earlier cash returns on investment, the ability to assimilate cultural and genetic improvements quickly, and the elimination of the need for replanting after each harvest. Perceived disadvantages include the high initial establishment and management costs, mechanical planting and harvesting techniques demand flat sites, and the uniform genetic make-up of the plantations increases susceptibility to disease and pests (SAJDAK et al., 1981). The economics of energy plantations relates to both the biomass production and energy conversion phases of development. For private landowners to participate in the production of biomass, for example, they must be reasonably assured of a positive return on their investment. Several studies have been undertaken to estimate the economic feasibility of forest energy production systems (BOWERSOX and WARD, 1976; INMAN and SALO, 1977; ROSE, 1977; PFEIFFER, 1978; NEENAN and LYONS, 1981). The considerable sensitivity of biomass production costs to such factors as site, rotation length, productivity levels and management practices suggests that it is unwise to attempt general statements with respect to the economic feasibility of forest energy plantations. Most studies suggest, however, that under favourable conditions satisfactory returns on investment can be achieved. Input costs include land rent, site preparation, planting, fertilization, weed control and harvesting. The significance of each of these to total costs varies from one study to another. The success of biomass energy developments will also depend fundamentally on the ability of investors in the conversion processes to obtain a satisfactory return, while producing energy at a price that is competitive with energy derived from conventional sources. Energy conversion processes under consideration include direct combustion for industrial and commercial heating, the generation of electricity in wood-fired power plants and the production of alcohols for use as a transport fuel. Again, site-

259 specific studies show considerable variability in economic feasibility (ROSE, 1975; BLISS and BLAKE, 1977; PFEIFFER, 1978; MORAN and NAUTIYAL, 1981; SEKINGTON, 1982). Concerns for energy efficiency, particularly in relation to energy projects, have become more pronounced in the last decade. In the United States net energy analyses are recognized as a fundamental aspect of researching new energy sources, as stated in Section 5 of the Non-Nuclear Energy Research and Development Act of 1974. However, research suggests that plantation forests are not energyintensive operations; INMAN and SAL0 (1977), for instance, have estimated that the energy stored in forest biomass exceeds the amount utilized in production by factors ranging from 10 to 15 times. Positive net energy balances were also estimated in an evaluation of forest biomass as a fuel source for a 100 MW electricity generating facility in Pennsylvania (BLANKENHORN et al., 1978). The most substantial energy inputs are fertilizer, transportation, harvesting and wood drying. On the basis of these results, it is expected that, in general, energy plantations would not be excluded on the basis of unfavourable energy budgets. The establishment of energy plantations and wood energy conversion processes are expected to have environmental repercussions. The production of biomass involves management practices very similar to those employed in conventional agriculture, and the environmental effects are much the same (ZSUFFA and MORGAN, 1983). The rapid growth characteristics of genetically improved trees and whole tree harvesting exert a heavy drain on soil nutrients (MILLER, 1981). Surface run-off may carry fertilizer to natural water bodies, and increased rates of eutrophication may occur (U.S. DEPARTMENT OF ENERGY, 1978). Similarly, pesticides and herbicides may be transported to water bodies, killing aquatic flora and fauna. The U.S. DEPARTMENT OF ENERGY (1978) suggests that large-scale energy plantations may contribute sediment loads that are at least equal to those from agriculture. Concerns also relate to competition for land and water resources (PLOTKIN, 1980). However, it is clear that careful management practices in agriculture can minimize environmental disruption, and it has been suggested that similar management techniques could be applied in forest energy plantations (PLOTKIN, 1980; ZSUFFA and MORGAN, 1983.

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(1981) listed 55 wood energy plantation projects operating in 14 countries. International cooperation in forestry energy research plays an important role in information dissemination. For example, the International Union of Forest Research Organizations, the International Poplar Commission and the Forest Energy Program of the International Energy Agency (IEA/FE) have greatly facilitated international interaction in forest energy research (DRYSDALE et al., 1983). The most active of these agencies with respect to forest energy plantations is the IEA/FE. Under a 1978 agreement between Belgium, Canada, Ireland, Sweden and the United States, a research programme was established which was designed to facilitate and improve work done at the interface between energy and forestry (MORGAN et al., 1983). Research activities were initially coordinated through four planning groups: (a) systems modelling and analysis; (b) biomass growth and production; (c) mechanization of production systems; and (d) conversion of biomass to energy.

Emissions of air and water pollutants will result from biomass conversion processes. Combustion of biomass, either for heating or in wood-fired thermal plants, releases into the atmosphere particulate matter and chemical pollutants, including CO*, CO, HCl and NO, (CANADA, DEPARTMENT OF THE ENVIRONMENT, 1982). The production of methanol may also produce emissions of CO and CO*, and liquid and gaseous hydrocarbons. Other chemical residues may be deposited in adjacent water bodies (CANADA, DEPARTMENT OF THE ENVIRONMENT, 1982). In general, the emissions of these pollutants are considered to be considerably less than from fossil fuel plants and opportunities exist to control emission levels (U.S. DEPARTMENT OF ENERGY, 1978; WAYMAN, 1978; CANADA, DEPARTMENT OF THE ENVIRONMENT, 1982).

International Plantations

Perspectives

on Energy

Interest in forest energy plantations has grown substantially since the late 197Os, and BENTE

In 1982 these were developed into ‘programme groups’ and systems modelling and analysis were

Table 1. Summary of international

Brazil

stageof

doubling

development

planned Aim

of reforested

alcohol

Types used

of trees

areas is

almost

produced

entirely from

plans not yet established research,

with

demonstration

biomass

very active

pine and eucalyptus

concentrates

plantations

willow

for

but

development

and

and modest

scale planting

France

Finland

energy plantations,

to replace petroleum

derivatives

survey of energy plantations

Canada

by the year 2OLM.

is in place and

biomass

production

with

and alder research

in energy

conducting

experiments

on

plantations

is being

breeding

considered;

39.5

species for fuel production

plantations

already estab-

lished,

further

developed on poplar

16 Number 3/1985

ha of research

and silviculture

of

60 ha to be

in 1983 -1986

willow

popular, aspen, eucalyptus

in

alder,

larch,

early stages Management system

spacing rotation

1 X 1.5 m 7-10 years

yields

12 odt/ha/a

short

rotation:

mini rotation:

spacing rotation

3 x 3 m 7 years

yields

5-7

density rotation

odtlhaia

spacing

0.3 x 0.9 m

rotation

l-5

yields

15 odtlhala

Funding

charcoal

source

and alcohol

co-generation

density

lMxx)-20000 plants/ha/a

rotation

5-15 years 4.5 odtlhala

years

of steam and

electricity, methanol

direct combustion, production Forestry

district

density

2OOL-4OMl

rotation yields

6 years

plants/ha 12 odt/ha/a

rotation:

yields End use

10 odtihala

yields short

mini rotation:

> 2OCW plants/ha l-5 years

heating

not available

methanol

European

production

Community,

French

programme

backed by

Canadian

institutional

and university of

(Energy from the Forest Program), Federal

Department of Agriculture, French Solar Energy

Industry and Mines and

Department of Regional Economic Expansion,

Committee

research

and Ministries

Agriculture, Commerce, Energy,

and Planning

Provincial

Service

Ministries

of

Treasury and Economics, Intergovernmental Affairs, and Natural

Resources

261

GeoforumNolume 16 Number 30985 Ireland

Netherlands

Italy

New Zealand

Stage of development

340 ha of energy plantations already established and a further 280 ha planned for 1983-1988

pilot plantations have been established across Italy. Trials dealing with silvicultural, harvesting and technological aspects

feasibility study of short rotation forestry began in 1978

preparing for the production of liquid fuels from wood but does not expect significant use of biomass before 2000

Type of trees used

Salix oquatica gigantia, five poplar clones and three alder species

oak (Quercus cerris, Q. tarneuo, Q. pubescm)

poplar

radiata pine, trials with willow and poplar

Management system

spacing

still under research

density rotation yields

rotation yields

Cl.3 x 1 m to Cl.6 x 1 m 3-5 years 15 odt/ha/a

electrical

generation

not available

thermochemical biomass gasification and methanol production

liquid fuels (methanol and ethanol)

National Agency for Pulp and Paper, Ministry for Agriculture and Forestry, and Commission of European Communities

European Economic Commission

National

End use

Funding

source

1600-2500 plants/ha 4-7 years 14.4 odtlhala

spacing

0.3 X 0.3 m to 1.2 X 1.2m 1-2 years 8.9-30.8 odt/ha/a

rotation yields

European Community, Dublin State Forest Service, National Institute for Agricultural Research, Department of Forestry and Fisheries, Irish Peat Development Board, and universities

Philippines

United

Sweden

Kingdom

Plant Material

United

Centre

States

Stage of development

a four-year development scheme is being implemented to establish 50 tree plantations in the country to fuel dendrothermal power plants

two major short rotation pilot farms have been established: 110 ha on abandoned farmland and 85 ha on unproductive peatland

programme began in 1979 to examine the feasibility of short rotation forestry and forest biomass for energy in the U.K.

demonstration plantations established on about 1500 ha in southeast, northeast and north central regions

Types of trees used

ipil-

primarily

birch, sycamore, alder, hybrid larch, nothofagus, Douglas fir, Corsican pine, Scats pine, western hemlock, Sitka spruce

eucalyptus,

Management system

spacing rotation yields

ipil

0.3 x 0.3 m to 3 x 3 In 4-6 years 5-25 odtlhaia

spacing rotation yields

willow

0.75 x 1.25 m 2-3 years 12-20 odt/ha/a

hardwood density rotation yields

coppice: 25Ol-1OKM plants/ha 2-6 years 15-20 odtlhala

single-stem plantation: rotation 12-20 years 8-12 odt/ha/a yields End use

Funding

dendrothermal (3 MW)

source

power plant

government supports program by loans

the

district heating

methanol

National Swedish Board for Energy Source Development

United Kingdom Department of Energy, European Economic Community

integrated into each of the other groups. The original member nations have since been joined by Austria, Denmark, Finland, New Zealand, Norway, Switzerland and the United Kingdom (MORGAN et al., 1983). The relatively recent origin of forest energy developments has afforded little opportunity for countries to collate, co-ordinate and summarise information on the various aspects of plantation

production

Leucaena leucocephala, cottonwood, sycamore, black alder, loblolly pine, maple, poplar, black locust varies with species and sites, e.g. spacing rotation yields

0.3 X 0.3 m to3x3m 2-7 years 6-17 odt/ha/a

ethanol, electricity direct combustions, gasification

generation, low Btu

Department of Energy, U.S Forest Service, individual states, universities and the private sector

projects. To provide an overview of the status, characteristics, location and extent of developments throughout the world, an international survey was conducted by the authors. Sources of information were diverse, and included previous surveys (BENTE, 1981; DAHL and LUNDBERG, 1981; ZSUFFA, 1982; DRYSDALE et al., 1983), personal communications, conference papers, newspaper reports and published research reports. The results of this survey are presented in Table 1.

262

Despite the considerable number of countries involved, very few have moved beyond the research stage of development. Only Brazil, Ireland and the Philippines presently report commercial-scale operations. In several other nations, including Canada, Finland, Sweden and the United States, however, research is at an advanced level and it is expected that the commercial production of energy from plantation forests will commence within the next few years. Financial support for energy plantation research is generally provided by the respective governments. In Brazil, Ireland and the U.S., however, extensive additional funding is provided by universities and the private sector. Although the species of trees used in energy plantations differ throughout the world, most countries have chosen a fast-growing hardwood. The most commonly used species are poplar (Canada, Ireland, Netherlands, U.S.), eucalyptus (Brazil, France, U.S.) and willow (Finland, New Zealand, Sweden). However, experiments have also been conducted in some countries with softwoods, specifically pine (Brazil, New Zealand, U.K., U.S.). Combinations of rotation length and planting density define alternative management systems. Although it was not possible to obtain complete information on management practices, it is clear from Table 1 that production systems vary considerably. Trees are planted either as seedlings or cuttings and in spacings that range from 0.3 m x 0.3 m to 3.0 m x 3.0 m. Planting densities reported range from 1000 plants per hectare to more than 35,000 plants per hectare. Rotations vary from 1 to 20 years and recorded plantation yields are from 4 to 30 oven dry tonnes of biomass per hectare annually (ODt/ha./a.). Anticipated conversion processes are selected according to the specific needs of the nation or region. The methods of conversion currently under development in the surveyed nations are: electricity generation (Canada, Ireland, Philippines, U.S.), production of alcohol fuels (Brazil, Canada, New Zealand, U.K., U.S.), pyrolysis to produce charcoal (Brazil), district heating (Finland, Sweden) and direct combustion for institutional, commercial and industrial heating (Canada, U.S.). Biomass from energy plantations will never supply the entire energy needs of a developed economy, but it could become an important component in a comprehensive energy programme (LEDIG, 1981). Individual countries have set different targets for

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16 Number 30985

the contribution of forest biomass to total energy supply, led by Brazil, which will soon have its entire land-based transportation system running on pure alcohol.

Forest Energy Plantations World

and the Developing

The extensive use of wood as a source of energy in developing countries and the consequent ‘fuelwood crisis’, which some believe to be the most serious energy supply problem in the world today (TORRIE and GOLDSTICK, 1980; HAYES, 1981; CHATIERJI, 1981), suggests an important role for plantation energy projects in these nations. Cooking and domestic activities in most Third World nations account for 67% of the energy used (TORRIE and GOLDSTICK, 1980), and the majority of this is in the form of firewood. As previously noted, the use of trees to supply energy to an increasing population, along with the further clearing of land for agriculture, is responsible for deforestation throughout the developing world, with the attendent environmental consequences arising from erosion and desertification. The problem of firewood scarcity in the rural areas is compounded by an increase in urban-based demands for firewood and charcoal. As a result, dung and agricultural residues are increasingly being substituted for firewood, instead of being returned to the soil to maintain its fertility (TORRIE and GOLDSTICK, 1980). Energy problems in the Third World are being accentuated through an increased reliance on fossil fuels, particularly in the commercial and industrial sectors. In 1975 liquid fuels accounted for approximately 60% of commercial energy use in developing countries (TORRIE and GOLDSTICK, 1980). Moreover, almost two-thirds of all developing nations relied on petroleum to supply 90% of the commercial energy, and in only 4 countries (India, Korea, Pakistan and Zambia) did liquid fuels account for less than 50% of energy used in the commercial sector (TORRIE and GOLDSTICK, 1980). There are several reasons to be skeptical about allowing economies to become increasingly reliant on imported fossil fuels. In common with all importing nations, developing countries face the inevitable fact that oil reserves are limited and that supplies must be regarded as unreliable given the unsettled political conditions characteristic of most oil-exporting countries. Additionally, the high price

263

GeoforumNolume 16 Number 30985 of oil consumes valuable foreign exchange, and this must be regarded as a more significant problem for the economically underdeveloped nations, many of which are suffering severe shortages of food and other basic necessities. A disturbing trend is that governments have not wanted to settle for ‘second-rate’ renewable energy resources while the industrial world flourishes on oil and nuclear power (HAYES, 1981). Consequently, the largest proportion of capital dedicated to energy has been spent on these conventional sources, even in countries that are 90% dependent on renewable energy. Resources which should have been devoted to the improvement of domestic supplies of renewable energy, HAYES (1981) suggests, have been squandered on technologies poorly matched to the real needs of most people in the Third World. Energy plantations could become an important component of energy programmes in the developing world; their advantages are many. Reforestation is badly needed to alleviate the serious environmental impacts; the development of energy plantations can be a labour-intensive operation, thus jobs could be provided for the rural poor; and problems associated with the introduction of new technologies are avoided, since the people are familiar with the use of wood as a fuel. Moreover, many Third World nations are considered to be well-suited for the establishment and growth of energy forests because they are richly endowed with sunlight. Furthermore, the populations tend to be dispersed, facilitating the use of decentralized energy resources. Therefore the establishment of energy forests could make a significant contribution to overcoming the problems of deforestation, while providing a domestic and renewable source of energy. In view of these advantages it is not surprising that some developing nations have already become engaged in the development of forest energy systems. Active programmes are underway in Brazil, the Dominican Republic, Honduras, India, Malawi and the Philippines (BENTE, 1981). The programmes in Honduras, India and Malawi are at present concerned only with providing adequate supplies of firewood, but elsewhere, in the Dominican Republic, for example, studies are being undertaken on the broader energy potential of forest plantations and on methods of production. In the Philippines several 3 MW dendrothermal power plants are presently being operated, with feed-stock supplied by 1000 hectare energy plantations. Brazil is a world leader in the development

and establishment of biomass energy programmes, and agriculture and forest energy plantations already contribute 25% of the total energy used. Cognisant of the severe problems posed by future energy supply, these countries have taken important initiatives towards guaranteeing reliable and renewable domestic energy resources. Conclusions

Prompted by an awareness of energy shortages and the high price of imported fossil fuels, many countries throughout the world are now exploring the opportunities afforded by renewable energy sources. Energy forests are recognized as having considerable potential and are becoming an important element in the energy programmes of several nations. Research conducted to date clearly indicates that appropriate technology is already available for the development of wood energy plantations and the conversion of forest biomass to useable energy forms. Moreover, energy plantations will apparently not be precluded on the basis of unfavourable economics or low energy efficiencies. While negative environmental impacts are expected, the effects appear to be considerably less significant than those associated with the development and use of conventional energy resources. For developing nations, energy forests represent a logical response to deforestation and exhibit the potential to provide jobs for many living in rural areas. Both developed and developing nations will benefit from energy plantations through the provision of a domestic and renewable energy supply source. Energy plantations are a relatively new concept, and although there has been a considerable amount of research undertaken already, much of it is technical in nature and little effort has been made to co-ordinate and summarise information. Towards this, an international survey of forest biomass energy projects was undertaken in order to identify salient characteristics of projects throughout the world. In addition to presenting the results of the survey, this paper has described the general characteristics of energy plantations and assessed their feasibility and potential as a future energy source. In balance, forest energy plantations represent a viable alternative for many countries, and with so many nations already actively involved in research and development, plantation forests will represent an important component in energy programmes throughout the world.

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Nonfossil Fuel Source, pp. 447-461,

ANDERSON, H., PAPADOPOL, C. and ZSUFFA, L. (1983) Wood energy plantations in temperate climates, For. Ecol. Manage., 6, 281-306. ANDERSON, H. and ZSUFFA, L. (1983) Hybrid poplar energy plantations in Ontario. In: ENERGO ‘83:

Proceedings of the Conference held in Toronto, Ontario, March 6-9, pp. 134-145. BENTE, P. (1981) The Bio-energy Directory. The Bio-

Energy Council, Washington, DC. BLANKENHORN, P. et al. (1978) Evaluation Procedure

for Consideration of Forest Biomass as a Fuel Source for a 100 Megawatt Electric Generating Facility. Penn-

sylvania State University, College of Agriculture Bulletin 820. BLISS, C. and BLAKE, D. (1977) Silvicultural Biomass Volume

of fuel biomass, In: Biomass as a D. Klass (Ed.). ACS Symposium Series, Washington, DC. LOVE, P. (1980) Biomass Energy in Canada: its Potential Contribution to Future Energy Supply. Energy, Mines and Resources, Ottawa. MARTIN, W. and PINTO, F. (1978) Energy for the Third World, Technol. Rev., June/July, 48-56. MATTHEWS, W. and SIDDIQI, T. (1981) Energy and environmental issues in the developing countries, In: efficient production

References

Farms,

16 Number 3/1985

V: Conversion

Processes and Costs.

MITRE Corporation, Virginia. BOWERSOX, T. and WARD, W. (1976) Economic analysis of a short rotation fibre production system for hybrid poplar, J. For., 74, 750-753. CANADA, DEPARTMENT OF THE ENVIRONMENT (1982) The Energy Brief: Comments on Alternative Energy Sources. Department of the Environment, Corporate Planning Group, Ottawa. CANADA, HOUSE OF COMMONS (1981) Energy Alternatives. A Report by the Special Committee on Alternative Energy and Oil Substitution, Ottawa. CHA’ITERJI, M. (1981) Energy and environment in the developing countries: an overall perspective and plans for action, In: Energy and Environment in the Developing Countries, pp. 3-25, M. Chatterji (Ed.). Wiley, New York. CLEVELAND, C. et al. (1984) Energy and the U.S. economy: a biophysical perspective, Science, 225, 890-897.

DAHL, L. and LUNDBERG, H. (1981) Biomass Energy Systems Identification, Report to the International Energy Agency Forestry Energy Project. DRYSDALE, D. et al. (1983) Energy plantations: the present situation and plans for 1983-88, In: Short Rotation Forest Biomass - Production Technology and Mechanization, pp. 3-11, P. Nilsson and L.

Zsuffa (Eds). Swedish University of Agricultural Sciences, Garpenberg. FRASER, M. et al. (1981) The energy plantation and the photosynthesis factory, In: Biomass as a Nonfossil Fuel Source, pp. 495-544, D. Klass (Ed.). ACS Symposium Series, Washington, DC. HALL, D. and MOSS, P. (1983) Biomass for energy in developing countries, Geojournal, 7, 5-14. HALL, D. et al. (1982) Biomass for Energy in the Developing Countries. Pergamon Press, Oxford. HAYES, D. (1981) Energy for development: Third World options, In: Energy and Environment in the Developing Countries, pp. 27-52, M. Chatterji (Ed.). Wiley, New York. INMAN, R. and SALO, D. (1977) Silvicultural energy farms, In: Proceedings, Fuels from Biomass Symposium, pp. 29-41, J. Pfeffer and J. Stukel (Eds). University of Illinois, Urbana, IL. LEDIG, F. (1981) Silvicultural systems for the energy

Energy and Environment

in the Developing Countries,

pp. 53-67, M. Chatterji (Ed.). Wiley, New York. MILLER, H. (1981) Wood Energy Plantations - Diagno-

sis of Nutrient Deficiencies and the Prescription of Fertilizer Applications in Biomass Production. Ontario

Ministry of Natural Resources, Toronto. MORAN, L. and NAUTIYAL, J. (1981) Estimate of Costs of Energy Production for Hybrid Poplar in Ontario, International Energy Agency Programme Groups ‘A’ and ‘B’ Meeting, Toronto. MORGAN, D. et al. (1983) Forest Biomass Energy and its Potential. International Energy Agency, Forest Energy Agreement, Toronto. NEENAN, M. and LYONS, G. (1981) Short rotation forestry as a source of energy, In: Energy from Biomass, pp. 232-238, W. Palz, P. Chartier and D. Hall (Eds). Applied Science Publishers, London. PFEIFFER, W. (1978) Economic Potential of Hybrid Poplar Based Fibre Production as an Agricultural Enterprise in Eastern Ontario. Ontario Ministry of

Natural Resources, Toronto. PLOTKIN, S. (1980) Energy from biomass: the environmental effects, Environment, 22, 6-13. ROSE, D. (1975) Fuel forest vs strip mining: fuel production alternatives, J. For., 73, 489-493. ROSE, D. (1977) Cost of producing energy from wood in intensive cultures, J. Envir. Manage., 5, 23-38. SAJDAK, R., LAI, Y., MROJ, G. and JURGENSEN, M. (1981) Forest biomass for energy: a perspective, In: Biomass as a Nonfossil Fuel Source, pp. 21-48, D. Klass (Ed.), ACS Symposium Series, Washington, DC. SEKINGTON, B. (1982) Wood and Peat as Fuels for Electricity Generation by Ontario Hydro. Ontario Hydro, Toronto. SZEGO, G. and KEMP, C. (1973) Energy forests and fuel plantations, Chemtech, 3, 275-284. TORRIE, R. and GOLDSTICK, M. (1980) Renewable energy in developing countries, Alternatives, 9,27-33. U.S. DEPARTMENT OF ENERGY (1978) Fuel from Biomass. U.S. Department of Energy, Environmental Development Plan, Washington, DC. WAYMAN, M. (1978) Wood-fired Electricity Generation in Eastern Ontario, Report prepared for the Royal Commission on Electric Power Planning, Province of Ontario, Toronto. ZSUFFA, L. (1982) The production of wood for energy, In: Energy from Forest Biomass, pp. 5-17, W. Smith (Ed.). Academic Press, New York. ZSUFFA, L. and MORGAN, D. (1983) Forest Biomass Energy Production - a Five-Year Retrospect of the Work of Programme Group ‘B’ - IEAIFE. Ontario

Ministry of Natural Resources, Toronto.