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• The strategy offered lower total capital costs and operating costs per tonne of feedstock,
whilst also offering a degree of flexibility to “manage” the ratio of ethanol/sucrose produced
depending on market conditions.
• Products such as yeast from the fermentation process were identified as high value protein
supplements for livestock industries, and other waste products, e.g. vinasse, were found to be
of significant potential agricultural value.
In addition to the ethanol program, the Brazilian sugar industry has become a major supplier of
electricity. The continually increasing demand for electrical energy and the complementary nature of
cogeneration during the dry season and hydro during the wet season increased the overall synergies.
These developments allow the Brazilian sugar industry to claim that it “produces energy for people
cars and houses” (sugar, ethanol and electricity). In Brazil an active trade also exists in bagasse, as a
thermal heat source both to other sugarmills for cogeneration, and to other markets such as the large
citrus juice processing industry.
Sugarcane offers the potential for multiple other products which “value add” the industry. Good
examples of this being the Industries in South Africa, and in particular Argentina, both of which now
make high quality paper from sugarcane bagasse. The larger mills in the Argentine Industry set a new
paradigm, where the value of paper products manufactured from bagasse matches or exceeds the total
value of all sugar products (Gomez, 2006).
A range of other products can also be produced from bagasse. Examples from the Australian Industry
(past and present) include the industrial chemical furfural (Watson L.J 2008), low density fibre-board
and thermal insulation, with many other products also being manufactured by industries throughout
the world.
Internationally the general move is towards increased cogeneration capacity in sugar mills to
maximise the value of bagasse and other available biomass. This is being achieved by:
• Significant increases in energy efficiencies in the sugar mills, allowing for large increases in
cogeneration output for the same fuel input (Lavarack 2004). This is the most common strategy
being adopted in Australia, with some additional capacity being achieved by importing bagasse
from nearby mills and other fuel sources such as woodchip. This strategy is currently being
used by the Industry in Northern NSW (Farrell R. Pers Com).
• Supplementary fuel supply in the form of trash collected from the field in a separate postharvest
operation. In many industries around the world, coal is routinely used as a
supplementary energy source. The cost of this trash relative to coal (including “green
premiums” where applicable) then determines the economic value of trash, and this is then the
driver of trash recovery strategies. Depending on individual circumstances this trash recovery
strategy may or may not be economic.
4.1.2 Supply chain implications
Some research was undertaken in both Australia and Brazil on the potential of separating the crop
components on the harvester and utilising parallel transport systems (Spinaze, 2002). The constraints
on the performance of the harvester trash extraction systems, the relative variability in the ratio of the
two product streams and the subsequent management of logistics of the operation have typically made
this a non-viable option.
The strategy of integrated cane + trash being delivered to the sugarmill, with trash separation from the
load at the sugarmill can be illustrated to give the lowest cost for trash at the mill for short transport
distances, with the benefit decreasing as transport distances increase. Depending on load densities, a
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