[Stoves] Example of missed opportunities was Re: is this new?

Tue Jan 22 09:39:27 CST 2013

Dear Paul

I will take this as your position:

>MAIN POINT:  This is a great example of missed opportunities because there
has never been seriously funded research on the multitude of controllable
variables in TLUD stoves!!!   We can see the possible variations.  But we
cannot prove them one way or the other simply by funding them out of the
pocketbooks of Paal, Paul, Crispin and others.  YEARS AGO we should have
resolved the issues of the Vesto stove being operated as a TLUD, or as a
different type of stove.   The Peko Pe features should be better understood.
As should the issues of Nurhuda's stove, and Belonio's, and Anderson's and
others.  Even people who have resisted TLUD technology for years are
becoming involved and still there is nearly zero coordination.  And any
financial support seems to be by-passing the people with experience with
micro-gasifiers, and instead is seeking isolated academic modelling that (I
suspect) will take years to have academic results.  So be it, but let's also
give some funds to the practitioners. 

And this as your call for direction of funding:

With all due respect for the need for proper "technology neutral"
distribution of funding, I am getting very tired of "technology neutral"
that gives equal (or more) weight to giving money (big money) to
"business-ready" operations that can start cranking out stoves to be counted
toward the 100 million by 2020.  Instead, the leading technology for lowest
emissions from solid-fuel cookstoves is TLUD (and other micro-gasification),
and it is not yet getting BASIC support that is needed.  

I have a problem with the justification. I don't see support going for
product development at all. The University of Johannesburg commercialisation
is funding (tiny) some actual blue sky product development. Who else is?
But the statement that a TLUD is 'the leading technology for lowest
emissions is based on what, exactly?

The lowest emissions of any stoves I have ever tested are all coal stoves.
They could have been made for burning wood and indeed are ignited with wood,
but it is important to point out that a high carbon fuel can be burned with
extremely low gas and PM emissions. The main claim for the cleanliness of a
TLUD is that it produces very low PM 'because it is a TLULD' mode pyrolyser
or gasifier making char (i.e. avoiding the burning of the carbon which is
implicitly blamed for creating the PM and CO with lots of fuel bed analysis.
By that I mean the way the fuel is broken down into combustible gases is
well described.

Now please consider a stove type which has lower PM emissions and does
exactly the same thing: breaking down the fuel into gases and does a good
job of burning it. Why is your call for research into these not included? If
they are cleaner than the current crop of TLUD's are they to be included?

That is where you lose me (my support) when the claim is put forth that
there is only a TLUD which has really low emissions. It was stated quite
off-handedly a few years ago, again at the Bangkok conference (without
evidence) and has been repeated since.  It is just not true. There are lots
of clean combustors.  The Austrians are doing wonderful work on biomass
burners.  Further, there are significant limitations imposed on the cook
when a TLUD is used which I won't discuss in detail here, but the goal is
not to support a device type that happens to get the combustion parameters
right. 

As you know there is a divergence of opinion between those who want to
produce charcoal and those who want to cook a meal with the fuel they have.
This is no trifling matter.  

The matter of refuelability is very important to users. I can report from
the field that people in a great many cases do not like the following:

Having to decide in advance of cooking how much fuel to add to the chamber
before ignition

Not being able to significantly refuel the stove while it is running

Not having significant control over the power

Not being able to use unprocessed fuel (meaning not cut and or chopped)

Not having any smoke to flavour the food

Not having hot coals to roast food on

Not being able to turn it off

Having to deal with end-of-run smoky ash.

The most strongly voiced objection in Indonesia was related to fuel
preparation. As soon as a conversation started about improved stoves people
volunteered that they were not interested in anything that required the fuel
to be chopped into little pieces. "Don't even start with that."

So what do we know is clean burning?

The Berkeley paper on stove comparisons (October) states that they did not
include coal stoves because, basically, 'people should not burn coal'. In
the webinar the matter was raised and Michael gave a quite different answer.
When a second question was put forward asking for an explanation of the
response the moderator did not allow it.  

If coal stoves had been included in the analysis, it would have been
perfectly obvious to anyone reading the paper that the new ones are by far
the cleanest burning in terms of PM and CO - the things we are supposed to
be minimising - and the best ones would have been sitting on the bottom left
corner of Tier 4, more like Tier 6.  Omitting them was inexcusable. Some
were TLUD's and some were not. If they were really worried about the CO and
PM emissions they would have included every available technology. That means
anything someone has shown to be very clean burning. You are worried about
funding for further development of a certain type of burner - I am still
trying to get the reviews to even admit the burners exist! When confronted
with the reality of their extraordinarily low emissions, they chose to
invent excuses (2) not to report them at all.

Surprisingly I am not suggesting we all start building coal stoves. It is
not universally available and coal is limited. But carbonised biomass will
be with us forever and we should know how to burn it properly.  What I am
pointing out is that the cleanest burning stoves are still not reported on,
let alone investigated as to why they work so well. What would happen if we
took the lessons from the designs and applied them to other fuels? You
follow?  There is nothing magical about TLUD's. Other combustors are just as
clean using the same fuels.   Why should research not be placed on all types
of combustors?

There is an overarching concern however. When these stoves were tested, what
was the test? How do we know these results have value if the test was
meaningless, or inappropriate? Are we drawing circles around our bullet
holes saying, this stove is 'right on target' after the fact? It is a bit
humiliating to stand in front of people and say, 'These stoves were tested
with a method that makes them look good; don't worry about the details.' 

People want to see clean burning and fuel efficient stoves. TLUD's are
largely (but not always) clean burning. Fuel efficient? Not so much, because
many of them are created deliberately or accidentally to create char.
Producing char requires fuel beyond the needs of the cook. If the 'test'
pretends that fuel was not consumed, then we have drawn a circle around the
TLUD stove bullet hole, again.

Product development funding should go where promise has been demonstrated.

Regards

Crispin

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