[Stoves] Tom Miles' Highlights from ETHOS 2007

[Kevin Chisholm]

Dear Tom
----- Original Message ----- 
From: "Tom Miles" <tmiles at trmiles.com>
To: "'Discussion of biomass cooking stoves'" <stoves at listserv.repp.org>
Sent: Friday, February 02, 2007 12:58 AM
Subject: Re: [Stoves] Tom Miles' Highlights from ETHOS 2007



Kevin,

> We discussed species and densities during side conversations at ETHOS. In 
> most field circumstances a wide variety of species are burned, even during 
> a single day. So identifying the species and their known characteristics 
> would be helpful.

I would suggest that while species is relevant, the most important factors 
in stove operation (from a fuel standpoint) are unit surface area and 
moisture content. These factors seem to be generally ignored when reporting 
results

> We actually know quite a bit about fuels. The challenge is to let the 
> stoves talk to us about what efficiency and emissions we can expect from 
> the different fuel qualities in use (types, size, moisture, density).

I think this is backwards... if the Stove Designer properly designs the 
stove for the wood at hand, the stove tells the fuel what to do. :-)

> At present we have some emissions and performance measurements for a 
> variety of stoves using kiln dried less-than-10%MC douglas fir, a medium 
> density softwood. The typical equilibrium moisture content for dry season 
> wood in most areas would be 10%-15% MC.

>One recurrent theme during the ETHOS presentations was the need to do 
>Indoor Air Pollution testing during the rainy or wet seasons. In the lab 
>this could be represented by burning high (650 kg/m3) and low (500 kg/m3) 
>density hardwoods and softwoods at 25% MC.

I've always been a great fan of chimneys and exhaust for eliminating Indoor 
Air Pollution. I can't see why they don't have general acceptance in the 
Third World, when virtually nobody in Canada or the US would consider living 
in a house that had an inside stove with no chimney. Is there any Building 
Jurisdiction in these areas that would permit construction of a building 
where a solid fueled stove was vented inside?

Best wishes,

Kevin

-----Original Message-----
From: stoves-bounces at listserv.repp.org
[mailto:stoves-bounces at listserv.repp.org] On Behalf Of Kevin Chisholm
Sent: Wednesday, January 31, 2007 7:15 PM
To: Discussion of biomass cooking stoves; rozisjf at club-internet.fr
Subject: Re: [Stoves] Tom Miles' Highlights from ETHOS 2007


----- Original Message ----- 
From: "Tom Miles" <tmiles at trmiles.com>


>Jean-Francois,

>You have demonstrated that we need several approaches to stoves and to
>stove
testing and sometimes we have to compromise some technical values for more
usable features.

>I would like to see the laboratory techniques for measuring performance and
emissions become closer to what is experienced in the field so that the
transition from lab to field is smoother. As Dean and others have emphasized
the lab tests are nothing more than development tools, but we need to make
them as close to the actual use as it is practical. Step by step maybe we
can reduce  the differences between them.

Wouldn't you think that Frank Shields is on the right track, with his
proposal to categorize fuels?

Best wishes,

Kevin