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Context - In coming years, the world’s energy consumption is expected to increase dramatically. While fossil fuels will remain an important source of energy, renewable energies will also gain importance, as a result of concerns over high fossil fuel prices, increasing greenhouse gas emissions and energy import dependence.
Could biofuels derived from forestry products and residues help meet the energy demand?
This Digest is a faithful summary of the leading scientific consensus report produced in 2008 by the Food & Agriculture Organization (FAO): "Forests and Energy, Key Issues" Learn more...
- Source document:FAO (2008)
- Summary & Details: GreenFacts
1. Introduction – What role can forestry and agriculture play in energy production?
While the global demand for energy is soaring, the sources from which
energy is derived are changing. This change is induced primarily by
concerns over high fossil fuel
prices, greenhouse gas emissions
and fossil fuel import dependence.
Alternative forms of energy have gained popularity as a way to address
these concerns. For instance,
bioenergy derived from biological
materials such as wood, agricultural crops and wastes, or dung is used.
If sustainably managed, bioenergy
derived from plants can be considered renewable because new trees or
other plants can replace those that have been converted to energy. Its
net benefit in terms of
climate change mitigation depends
on the balance between carbon dioxyde (CO2) captured during
plant growth and CO2 released when producing, processing,
transporting and burning the fuel.
Increasingly, agricultural crops such as oil palm, sugar cane, maize,
rapeseed, soybeans and wheat, are being used to produce liquid biofuels,
mainly to power vehicles. But the increased use of agricultural lands
for growing energy crops may compete with food production, causing
increased food prices and
deforestation. This has raised
questions about the true role of such
biofuels in mitigating
climate change. A new generation of
biofuels derived from wood, agricultural and forestry residues, and
certain grasses is being developed. It is expected to be more energy
efficient and to generate less
greenhouse gases than current
generation biofuels (i.e. made from agricultural crops), without
competing with food supply. If
sustainably managed, large forested
areas could serve as a source for these second-generation biofuels.
2. What are the trends and prospects of energy supply and demand?
In coming years, the world’s demand for energy is expected to increase
considerably as a result of population growth and economic development,
mostly in Asian countries. Although
fossil fuels will play a major role
in meeting that increased energy demand over the next 20 years, policy
decisions will heavily influence the types of energy sources that will
The share of renewable energy on
the global energy market is expected to increase slightly until 2030.
The biggest growth in renewable energy production will likely occur in
North America, developing countries in Asia and Central and South
America. The United States, China and India will remain the top three
consumers of liquid biofuels. Overall, renewable energy sources will
continue to be used primarily for heating and cooking, but their
contribution to power generation and transport will increase.
Wood-based energy is used both for domestic and industrial purposes.
Countries such as the United States, Canada, Sweden and Finland often
use by-products of wood processing to produce electricity. Developing
countries mainly use fuelwood and
charcoal for domestic heating and cooking, but increasingly also for
commercial activities such as fish drying, tobacco
curing and brick baking. Their
consumption is growing due to population growth, particularly in African
and South American countries.
Future energy choices will primarily depend on the price of
fossil fuels, on the availability
of alternatives and on political priorities such as mitigating
climate change or reducing
dependence on fuel imports.
3. How is bioenergy produced?
Open fires convert only 5% of the wood’s potential
Credit: Roberto Faidutti
Bioenergy can, for instance, be
derived from solid woodfuels, such as
fuelwood and charcoal or from
liquid biofuels, such as
black liquor (a by-product from
the paper industry) and ethanol
obtained from wood. Energy from woodfuels can be produced through
various processes that differ in terms of energy efficiency,
installation cost, carbon dioxide
emissions and amount of work needed.
Burning solid woodfuel in an open
fire only converts about 5% of the wood’s potential energy, but
technologies exist that can increase efficiency up to 80%. Such
efficiency is achieved by combined heat and power systems, which use
wood to produce both heat and electricity, and by some modern furnaces
that burn wood pellets made of dried, ground and pressed wood residues.
Other technologies include power boilers which burn wood wastes from
sawmills to generate electricity and
gasification, which is the process
of heating wood residues to a very high temperature to produce gas that
can in turn be burned very efficiently to produce heat and power.
‘First generation’ liquid biofuels include
bioethanol and are derived from
various food crops that vary by geographical location, for instance
cereals, rapeseed and sugar cane. These
biofuels have attracted a lot of
attention because of their relatively low prices and advanced state of
development. However, the increasing use of certain food crops for
biofuel production can in some cases significantly raise global
greenhouse gas emissions as a
result of deforestation and land
degradation. Recently, new plant
species have been tested that grow
well on marginal lands and could therefore produce biofuels without
directly competing with valuable lands.
In addition, technological developments are expected to increase
future interest in more efficient ‘second generation’ liquid biofuels,
which are not derived from food crops, but from plant materials such as
agricultural residues, forestry residues, and wood from
4. How much can forestry contribute to future energy demand?
Energy generated from the residues of forestry operations could be
To what extent forestry will contribute to future energy production
will depend on a series of factors: the ability of wood-based energy to
meet the recent energy policy objectives, the socioeconomic and
environmental costs and benefits of
wood energy production, and the
policies and institutions that determine forestry practices. Developing
countries often tend to have small budgets and will therefore need to
carefully assess the risks and benefits of investing in
The amount of energy that can be generated from the residues of
forestry operations is considerable. Efficient methods of harvesting and
transportation could further reduce the cost and environmental impacts
of producing such energy. Most of the wood for future
bioenergy production will likely
come from existing forestry operations unless economically competitive
technologies for the production of second-generation
biofuels become available.
Forest plantations are another
major source of wood energy that
will likely increase in the future. To be economically viable, such
plantations will require efficient
harvesting, good logistics, and high-productivity.
The efficiency of liquid biofuels in terms of
greenhouse gas emissions compared
to petroleum motor fuels varies from one type of biofuel to the other.
The greatest decreases in greenhouse emissions result from the
conversion of whole plants to liquid biofuels. In terms of cost
efficiency, sugar cane is currently the most economically attractive
option for liquid biofuel, but
future technological developments could make wood-based
second-generation biofuels competitive.
5. What are the implications of increased use of bioenergy?
Growing demand for bioenergy could result in
Credit: Masakazu Kashio
Bioenergy has the potential to
promote economic well-being, allow better use of unproductive land,
increase energy security and reduce
greenhouse gas emissions. However,
this potential can only be realised by also addressing problems
associated with the large-scale production of
biofuels, such as
poverty, impacts on
climate change, and water scarcity.
The expansion of bioenergy can
have both positive and negative impacts on livelihoods. It may create
more jobs and improve energy security. However, it may also lead to land
disputes and human rights abuses, particularly when large energy
plantations are involved.
Competition for land and agricultural products may raise farmers’
incomes but also food prices.
A growing demand for bioenergy
could result in deforestation to
make way for agricultural land, but on the contrary agricultural land
could be converted into wood
plantations if wood becomes the
main resource for bioenergy. Depending on how it is done, using
degraded lands for the expansion of
bioenergy plantations could have either positive or negative effects on
soil fertility, erosion,
biodiversity, water flow and food
availability. Given the many advantages and drawbacks to bioenergy
development, countries must consider the long-term environmental, social
and economic impacts of various energy alternatives.
6. How should bioenergy policies be developed?
Sustainable management and development should be part of forest and
Credit: Masakazu Kashio
To counteract the potentially adverse socio-economic and environmental
impacts of large bioenergy
projects, effective land-use planning is needed. In addition,
information transfer from developed to developing countries should be
National forestry and energy goals should reflect the principles of
sustainable development and sustainable
forest management. In particular,
forestry and energy policies should:
- integrate bioenergy
issues into forestry, agricultural and other land-use policies;
- consider environmental, economic and social impacts;
- ensure information is readily available to anyone involved in
the management of forest
- consider areas such as land-use management, rural employment,
and environmental protection to seek
synergies and avoid negative
- facilitate bioenergy development through research, education
and training, and through transport and infrastructure measures;
- find a balance between agriculture and forestry, as well as
between domestic and imported sources of
- consider the impacts of bioenergy on other economic sectors;
- undergo regular monitoring to avoid negative environmental and
social impacts; and
- prevent the destruction of natural resources and the loss of
The current situation represents a major opportunity for the forestry
sector to contribute to increasing energy security and mitigating
climate change by reducing
dependence on fossil fuels.
In coming years, the world’s energy consumption is expected to
increase dramatically, particularly in Asia. While
fossil fuels will account for most
of the increased energy supply, renewable sources of energy will also
gain importance, as a result of concerns over high
fossil fuel prices, increasing
greenhouse gas emissions and energy
Bioenergy, including energy
derived from wood and other plant materials, accounts for a significant
proportion of the current energy supply from renewable sources. In many
of the world’s developing countries,
fuelwood and charcoal (traditional
bioenergy) remain the primary source of energy. In industrialized
countries and particularly countries with large wood processing
industries, wood energy is used for
both domestic and industrial purposes.
Currently most liquid biofuels are produced from food crops and yield
low economic and environmental benefits compared to
fossil fuels. The increased use of
these crops for energy production may even compete with food supply and
lead to increased deforestation.
However, it is expected that a new generation of liquid biofuels will
become available in the next decade using wood as well as agricultural
and forestry residues. This technology is expected to become
commercially competitive and generate much less
greenhouse gases compared to fossil
fuels. Such second-generation liquid biofuels produced from woody
biomass rather than from food crops
would also reduce competition with food production.
Wood-based energy is among the most efficient sources of
bioenergy. At present, it is
particularly competitive when using wood residues from the wood
To avoid negative environmental and socioeconomic impacts, the
expansion of biofuel production will need to be accompanied by clear and
well enforced regulations.
Future demand for bioenergy will
depend largely on the policy measures that will be adopted.