[Stoves] RE Adding a fan

[Dean Still]

Dear Jigme,

If you add a fan to a Rocket stove it works whether the fan is on or off.
Using the fan cuts CO and PM, Time to Boil but fuel use stays in the same
range.

I also prefer chimneys but it's practical to explore options. In India, by
the way, a 10' chimney 4" in diameter made from asbestos/cement costs about
$1.50. Really good .6g/cc firebrick costs about twenty five cents. A 100KW
gasified electric generator costs $75,000. A good enough hammer costs $1.

In the places I have visited folks usually use long sticks of wood to cook
food. Batch loading has many advantages but for folks who use long sticks
it's often necessary to offer them cleaner burning stoves that do not need
further prepared fuel.

Best,

Dean

-----Original Message-----
From: Jigme Rangdrol [mailto:rangdrol at turboisp.com] 
Sent: Saturday, May 20, 2006 10:42 AM
To: Dean Still; Stove List
Subject: Re: [Stoves] RE Adding a fan

So am I missing something here?

Each layer of devicevness adds cost and increased failure rate in a 
multiplying wave so that efficiency and safety and health limits are 
rapidly breached.
So far every model I make comes back to the same problem.
The real fan problem for all fan stoves is how they burn when the fan fails.
The stove must work on its own without the fan and that puts a lot more 
pressure on the fan.
Since a chimney can produce the same effect it is going to be superior 
due to its lack of moving parts so there is little or no incentive for 
the user to go to an electric fan or a "Frankenstove".
Escapements are cheaper and more reliable than electric drives but also 
easily separated from the stove and less mobile.
By cheating and making "Fixed" in place stoves, the much more reliable 
mechanical fans can be used instead of electric drives but the user has 
to really want the extra efficiency enough to go the extra expense and 
give up mobility. That user does not need a non-chimney stove.

Why would they want to?

SNIP

>
>Cooks like how it cooks food
>Side fed long sticks
>Fast to boil
>Fuel efficient to simmer (good turndown)
>Safe
>When used does not damage health of user (ventilation helps a lot here!!)
>$2-$5
>Long lasting
>
>  
>