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FAO/UNEP/UN-Energy Bioenergy Decision Support Tool -
MODULE 7: Deployment and Good Practices
OVERCOMING BARRIERS TO IFES
The higher complexity of dealing with multiple products and
processes, as well as the multi-sector nature of IFES presents
a number of barriers to their implementation and wide-scale
dissemination, at both farm and beyond farm level (FAO, 2011):
• The higher level of complexity of some IFES requires greater
technical knowledge and management skills, which may be
unavailable or costly;
• Reliability of the systems must be established at an early
stage, before major upscaling is attempted, so as to prevent
a bad reputation that will discourage replication;
• Financing
is often related to the investment required for
the energy conversion equipment, which tends to be more
expensive at higher effciencies and environmental perfor-
mance. In order to make such options affordable for indi-
vidual small-scale farmers, access to fnancing mechanisms
such as micro-credit schemes needs to be offered.
• The increased
workload
often experienced with IFES can
make the systems less attractive to farmers, and therefore
needs to be considered at the design phase. Where multiple
crops are grown on one piece of land, as in Type 1 IFES, or
where there is a diverse array of inter-connected crops and
livestock, as in Type 2 IFES, there tends to be less scope for
specialization and mechanization, thus requiring signifcant
manual input.
IFES can give rise to
competition
for wastes/residues used
for energy production vs. other needs/uses, such as soil
fertility or for animal feed; the system design needs to
consider these other uses based on their relative value in
socio-economic and environmental terms.
• Trade-offs
in the use of resources (land, water and nutri-
ents) will need to be balanced, as competition for biomass
for food, feed, fertilizer and fuel increases; in general, the
intrinsically higher effciency of IFES itself will address such
trade-offs in the longer term, but short-term conficts that can
present a barrier to implementation will nevertheless need to
be managed.
• The existence of multiple products and markets in IFES
requires broader
access to markets
for agricultural and/or
energy products; the distribution and transport channels for
the various products must be considered as well as their
competitiveness in price and quality.
In addition to such specifc barriers, since IFES will often be
located in rural areas, they will also face many of the traditional
barriers associated with rural-based agro-industries, such as
communications, transport infrastructure, technology transfer,
availability of skilled labour, market logistics and poorer repre-
sentation in political processes. Overcoming such barriers will
require innovative approaches in the design of both the technical
package of options and the institutional support mechanisms.
Co-products
As discussed in many of the integrated food-energy systems
(IFES) above, the issue of co-products is critical for the long-term
sustainability of bioenergy systems. The availability of various
energy and non-energy co-products improves the energy balance
and economic viability of the “primary” energy product. The disad-
vantages of low energy density and the high land use intensity
that characterise bioenergy systems means can thereby be partly
overcome. In the longer-term, as non-renewable resources (i.e.,
not only fossil fuels) become scarce, the non-energy co-products
will take on special strategic importance, since biomass will be
needed to replace chemicals and materials. The modern biorefn-
ery is proposed to achieve better synergies and effciency in the
production of energy and non-energy from biomass.
http://www.nrel.gov/biomass/biorefnery.html
There are two main aspects to consider in co-production: energy
cascading and the set of relevant co-products. Energy cascad-
ing refers to the case when two or more different energy carriers
result from conversion platforms: combined heat and power
(CHP) plants that produce electricity and heat are the most
common example. Another example of multiple energy products
is the anaerobic digestion of biogas from waste stillage at ethanol
plants. Anaerobic digestion plants are often utilized alongside
sugar factories, but can also more generally from be sourced
from other appropriate wet biomass source. Anaerobic digestion
can produce triple benefts: in addition to the biogas produced, it
reduces health problems and odour from wastes, and also have
as a by-product an odourless and nutrient-rich effuent, which
preferably can be used as fertiliser.
Anaerobic digestion thus exhibits also the second type of
co-production, in which there are several distinct by-products or
co-products. The economic fexibility of multiple products adds
long-term value. For example, agro-industrial operators with the
capacity to produce more than one product, such as sugar and
ethanol or starch and ethanol, and have the ability to alter the
ratio between the two, can optimize its production to exploit price
variations and thus make a higher proft. Brazilian sugar/ethanol
producers can adjust their production ratios somewhat based on
the relative price of ethanol and sugar.
There are trade-offs to be made in the market and end-use alloca-
tion of by-products. In some cases the by-products can be used
for electricity or heat production, but there may also be an option
to optimise the by-products for other uses such as animal feed
or fertilisation. For instance, bagasse can be made into paper,
burned for energy or fed to cattle. Although electricity produc-
tion from bagasse improves the energy balance, it may lead to
deforestation if cattle farming moves to other areas; consequently,
the GHG balance may actually be better if the bagasse is used for
animal feed in high productivity cattle production and the electric-
ity is imported from other sources.
Sustainable Agricultural Practices
The use of agricultural or pasture land for energy production can
create additional land use and resource pressures unless some
degree of agricultural intensifcation is adopted. At the same
time, intensifcation must aim to minimize negative ecological
and environmental impacts. Sustainable intensifcation aims to
increase productivity and provide economic benefts to farmers
by capitalizing on inherent ecological processes and capturing
the value of ecosystem services. An overview of good practice
methods that can help to address agricultural land use pressures
is provided below and a summary of specifc measures or actions
in relation to environmental or ecological goals is given in Table 1.
The overview and the table are for general reference purposes,
since the applicability of particular methods or actions will of
course depend on site-specifc and feedstock-specifc factors.
AGRO-FORESTRY
Agro-forestry methods integrate trees into agriculturally productive
landscapes to preserve the crucial role that trees play in almost
all terrestrial ecosystems, where they provide a range of products
and services to rural and urban people. Examples of the func-
tions performed under agro-forestry schemes include fertilizer
trees for land regeneration, soil health and food security; fruit