Micro-gasification: Cooking with gas from biomass - Amper

Micro-gasification: Cooking with gas from dry biomass
Some burner units can be fitted into existing stove structures, broadening the options of
fuel and enable the choice of fuel type according to what is available at the moment.
Some gasifier stoves can easily be fitted with a heat resistant glass of a paraffin lamp so
that they can provide light during operation. This is a good argument when users resist
to change from the open fire to an enclosed fire chamber because of the loss of light to
brighten the cooking space.
Not enough data are yet available to quantify emissions and fuel consumption of different
micro-gasifier models. Some tests like the 5-litre Water-boiling tests to determine
fuel consumption are not applicable to certain batch-feed micro-gasifiers. New testing
protocols are being developed to suit micro-gasifiers.
There is no single answer to the numerous needs of the world. Some stoves can do one
task really well but are not suitable for other tasks. The solution is in a variety of custommade
or purpose-designed applications. This variety of designs is imperative and there
is no ‗superior‘ or ‗best‘ design. There is no ‗one-size-fits-all‘ design, but always a ‗onesize-fits-some‘.
Some designs are more appropriate in certain scenarios than others.
Therefore we need to know the uses of the different designs and how to make choices
in each set of conditions.
Some features are valued differently by different users: batch-feeding of a stove is seen
by some as a big advantage, as they don‘t need to tend to the fire every 2-5 minutes.
Others consider this a disadvantage, as the entire container needs to be exchanged and
reloaded at the end of the burn.
Some micro-gasifiers have been optimized for specific fuels, making them excellent in
some situations but inappropriate in other places.
Micro-gasifiers are not always an appropriate solution for a household stove, depending
on fuel access. It does not make much sense to chop up big chunks of wood with a machete
or an axe, so that the fuel becomes small enough for the use in a micro-gasifier.
Where access to stick-shaped wood is still reasonable, appropriate stoves for this fueltype
should be encouraged. Micro-gasifiers should never been seen as a threat to existing
systems, but always as a complementing element, as they offer the opportunity to
use available and often discarded biomass as a fuel, that other stoves cannot burn
cleanly. There is more information on fuel and fuel preparation in Chapter 3.
Some developers (Belonio, Reddy, Karve, Anderson, Donnelly, and others) offer many
more designs and models than shown here. Those designs might be important in niche
situations. Links are provided for further reading.
There are also different concepts of producing stoves, ranging from entirely local production
based on scrap or new materials, to partially pre-manufactured and locally assembled production
or entirely ‗foreign‘ manufactured imported technologies. Each concept has its own
advantages and disadvantages. On a case-by-case basis, the situation needs to be evaluated
for the most feasible option. Sometimes a sequential approach is more effective, starting
with one type to lead to another in the long run.
HERA – GIZ Manual Micro-gasification Version 1.01 January 2011
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