Re: Practical boiling

["Crispin" <crispin@newdawn.sz>]

Dear Stovers

I read through the detailed response from Kevin and as I am proposing
something specific, I feel I should clarify a few things so that Kevin's
suggestions do not become the measure of my vision.

First, thanks Kevin for the responses to all the rather lengthy post I sent.
I feel that it is important, in a consultative environment, to place our
best contributions on the table.  I am not comfortable with the either-or
dichotomy that some consultatons become so please understand that I am not
advocating a practical boiling approach as a substitute for a suggested
rapid boiling test which received a lot of support.  I am trying to address
the fair concerns made by other list members that such a contest is not
useful.  While I agree that useful information could flow from such tests,
it may become so deranged from reality that we will be labelled as
pipe-dreames drifting into a theoretical world where the results are
literally academic.  I am sensitive to such criticism.

I frequently drift into such spaces because of the nature of my working on
the edge of certain technologies.  Our hand operated rock crusher is one
technology that was pretty much dismissed out of hand by all and sundry
until we found a small mathematical island (aftre two years) on which the
theory proved to be practical and we now have a working machine that meets
many, seemingly impossible demands of price, performance and maintenance.

With that in mind, I feel that the work discussed on this list can fairly be
described as mostly theoretical and not much practical.  Theory is required
but more practice would be far better.  Paul Anderson's approach is to try
just about _anything_ even when it seems impossible at first.  This
omnivorous approach often leads to startling advances.

I do not propose to start a 'practical stoves' list. I think the talent
conglomerated here should concentrate time and discussions on applying our
resources and energy to something with immediate application.  Let me repeat
for emphasis that I am not against having speed boiling contests.  But
before this evening was out, based on the idea that a rapid boiling system
for water purification could be developed for Moçambique, I have already
garnered an 'appointment' with WHO in Moç. about the proposal to look at
developing, for immediate implementation, a water boiling system which can
be replicated on a national scale.

This was done between my message suggestion the format and this one. There
is such is the vacuum of technologies for workable solution to water
purification problems, that the reception was like that!

I will only respond to the most important part of Kevin's message - please
forgive the brevity.

>You are proof that the "Fast Boiling Contest" concept is beneficial:

It was my feeling that I was showing that such a contest offers little of
benefit, even though it is interesting to do.  I may be wrong about this.  I
have tried to communicate my opinion that the penny popping measure of the
boil is not applicable to very high heat output tests (which is where rapid
boiling is headed) as it does not measure boiling.  I can 'cheat' by
building a stove designed to focus heat on the water line in the can so that
it boils almost immediately at the waterline, certainly getting that effect
in less than 60 seconds without heating up the rest of the water much at
all.

As I work in the private sector and can only deem a product successful when
it is adopted, I have a very strong practical streak.  Thus when I wrote
"...the combination of fuel+stove+water container must function as a package
to deliver convenience, sterility, affordability and sustainability in terms
of technology transfer and fuel type" I couched it in the terms used by the
A.T. designer.

This is an important comment:

>I think it is a mistake to "channel a R&D project too early.

A contest to develop a water boiling system is the inverse of the suggested
channeling.  It is rapid boiling that is the focussed, channelled activity.
The brief is that the designer come up with a system meeting criteria that
does not feature compartmentalised progress, even though such progress will
take place in the development stage.  My appreciation of specialized
contests exists, but the test is in the eating, so to speak. I feel that the
comment reflects the position that what I am laying out for discussion
channels things away from something more general which is not the case.

>What you are suggesting is the development of a stove system for a
>specific application.

I did use a practical application as the ground work for the contest's
approach to stove development.  However boiling water is by no means a
limited application.  Most families boil water more than once a day.  My
approach is neither limited nor health specific.  The brief for the
provision of a system for preparing infant formula is because of immediate
need and will lead to stove developers having opportunities that they have
pined for for years.

As to the importance of the container:
>However, for simplicity in running a contest, I feel that a
>standard container is a big first step toward a
>"level playing field."

This is a legitimate concern.  I am drawing everyone's attention to the fact
that the can is part of the water boiling system and therefore impacts
significantly upon the system's efficiency.  It would be a pity if a
fuel-stove-pot combination that was remarkably efficient were to be
disallowed from contests because of a restriction in contest rules about the
container.  It would look silly if people took a Wood burning Yellow 6.75
stove off the street and entered it in a contest only to find it is an
Orange 4.13 because of the can.  If you can all bear with me I will make an
example.

A boiling contest is a test of a number of facets of cooking including fire
preparation, ignition, stack draw, primary air control, secondary air
heating and flow, fuel load, heat direction, heat transfer, reflection and
re-radiation, turbulence, gas velocity and many chemical reactions (thanks T
Reed).  To leave out the variability of the pot, substituting a standard can
in its place, necessarily means that the other variables will be modified to
generate the most influence on the can's contents.  For the most part it is
unrealistic as an example of cooking and I proved it to myself when I saw
the heat transfer rate through the thin walls.

It would be more valuable to test the heat production of the stove, rather
than its influence on a can.  My reasoning on this is that with the can
standardized, the test is of heat generating capacity and to a lesser
extent, sustainability.  I am now convinced that for less than $10 I can
built a 50KW stove for contests.  A 100KW wood burning stove that would burn
through the can in seconds may not be out of the question.  I am already
convinced that it is pointless.  Still, I understand the interests of myself
others in doing so for fun.

But why is it pointless?  I have a very good anthropologist friend who
refuses to play any games with me.  At all.  I find this disturbing because
I like Double Freecell and Chess and especially Scrabble.  He says that as
soon as he knows it is a game, he completely loses interest.  While I
believe him, I don't like it.  Seems antisocial.  I am working in an
environment where development capacity that is misdirected is deemed to be
antisocial.  That is a kind of take-it-or-leave it opinion of others, but
the deprivations and deaths of enough people make you think that way after a
while.

I have dozens of people tour our workshop every week.  I point out to them
the various stoves we make and are developing, though it is a very minor
part of what we do, less than half a percent of what we sell.  When I show
them a very fast stove and they ask what use it has, I have to reply, "None"
because that is the truth.

>Health workers have no particular input into eventual stoves
>made for cooking purposes.

If that is true, shame on the stove developers for failing their
constituency!

>would you agree to head up a Contest to develop the
>stove system that is of greatest interest to you?

I would be prepared to assist with a contest that produced stoves of the
greatest interest to stove users. I have made stoves with sustained output
of 20 KW (i.e. 8 hours a day).  My understanding of present interest is in
saving fuel and reducing harmful smoke production which in my opinion are
directly related.  It is my observation that a far faster system for
producing boiled water for general consumption is the most urgent need in
non-electrified communities.

A specific need in Moçambique is that of a stove which will burn coconut
husks with good secondary combustion.  I have only proved in principle that
it is (barely) possible using an unmodified Tsotso stove.  I deem that to be
specialized and the boiling of water to be general.  Just my opinion.

Several times in the past couple of centuries people have advocated the use
of a water container which looks like an old fashined conical oil can.
Inside it has a conical floor that is approximately parallel to the outside
surface.  They have a high surface area and limited water capacity.  They
probably quintuple the heat collection that a can or flat bottomed pot has.
They are well known and were marketed commercially several times, often for
very rapid heating of a single cup of tea.  Some will boil a cup of water
with a candle in a short time.  One Persian scientist hundreds of years ago
famously heated a bath of water with a candle using a related system.  This
device, conjoined to a suitable stove, would greatly assist the infant
formula project.

We should, as a stove developing community, decide if we are creating heat
generating devices (stoves), or product delivering systems (hot water/cooked
food).  Without limiting people's freedom to follow any direction of their
choice, I make a modest call for people to focus their energy on the
problems that beset their time and generation.  I, as Einstein said of
himself, may only have one or two good ideas.  I would like them to be
practical ones.

I will offer to fairly test and rate any stove sent to me at Plot 525,
Matsapha Crescent, Matsapha Industrial  Site, Swaziland, or P.O. Box 3223
Manzini Swaziland.  I will put the results on our website.

In the meantime I think we should invite people to hold contests of any
nature and consequence that people have enthusiasm for.  The publicity value
is good for stove and environmental groups alike.

The King's wife Inkhosikati LaMagwaza telephoned today and congratuated me
on our achievements of this past week and suggested that we do a
demonstration of the boiling on the local free-to-air satellite TV Channel
S.  If that is what it takes to generate interest from the public, then we
should proceed apace with the fireworks!

Regards
Crispin sweating it out on a hot January night.


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