Letaba Biomass to Energy PDD - MyClimate

Introduction
PROJECT DESIGN DOCUMENT FORM (GS-VER-PDD)
Voluntary Offset Projects - Version 01
Annex 2
BASELINE INFORMATION
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page 38
In this section the small-scale methodology used is discussed. Before this is done however it is necessary to set out
certain important facts about the plant at Letaba Estates in order to place the methods used and calculations made
below in proper perspective.
Firstly, the project baseline at Letaba Estates is the coal used in two applications namely the peel driers and the
boilers respectively. Phase 1 will see the former switching to biomass and Phase 2 the latter. The energy efficiency
measures implemented in the peel dryers and steam plant will eventually see the feedstock/input requirement being
lowered – however in the baseline it remains at historical efficiency levels and based on coal rather than biomass.
Secondly, the plant produces two categories of fruit juice namely citrus and single strength. The citrus product line
processes oranges, navels, grapefruit, lemon, Midseason, mineola and Valencia. The single strength fruit product
line processes banana, butternut, guava, granadilla, kiwi, mango and paw paw. Citrus juice is made in concentrate,
meaning that much water has to be vaporised. Single strength juice however is made in its final form and merely
heated. For partially this reason and because output of citrus is measured in concentrate while output of single
strength juice is measured in final juice produced, the emissions factor for citrus concentrate is much higher than the
emissions factor for the single strength juice line. Because, as prescribed by AMS III.B, annual output (concentrate of
citrus and final product single strength fruit) produced will be monitored to establish emissions reductions and
because the relative quantities of fruit juices made differ from year to year, it is necessary to distinguish between the
energy used to process each category of fruit in order to always be able to determine emissions reductions
regardless of relatively how much citrus concentrate and single strength fruit juice is produced in each year of the
Project Activity. Separate emissions factors are thus determined for citrus concentrate and subtropical/singe strength
fruit juice.
Thirdly, in the baseline coal has been used at the processing plant to both produce steam and dry the peels.
Accurate records exist of how much coal was used but historically no distinction was made between coal going to the
boilers and coal going to the peel dryer. There also was no constant ratio between the amount of coal being put to
these two different uses. It therefore becomes necessary to establish historical emissions not only for each tonne of
citrus fruit juice and each tonne of single strength fruit juice produced but also for each tonne of peels dried in order
to be able to monitor and calculate emissions reductions by monitoring the quantity of fruit juice produced
(distinguished as between single strength and citrus) and the quantity of peels dried. The emissions factors are thus
theoretically calculated.
Fourthly, at present the ash from the boilers at Letaba is landfilled on the property. In the Project Activity less waste
will be produced and it will be landfilled as before.
Fifthly, the new baseload multi-fuel boiler and also the remaining boilers (when they are still needed in times of high
steam demand) will be fired initially and after periodic maintenance by using solid wood chunks. There will thus be
no use of this auxiliary fossil fuel, however, should an emergency necessitate the use of coa,l the use thereof will be
monitored.
Sixth, the calculations further in this document are based on starting with the aggregate amount of coal used
historically for both the peel drier and the boilers and first establishing how much was used by the peel drier. This is
done by the theoretical model developed and included below. By subtraction it is then possible to establish how