Entries by Kim Still

Turn Down Ratio

One of the things that I like about the IWA Water Boiling Test is that it mimics the boiling and simmering functions of cooking food. Wood burning stoves are notorious for being too slow to boil big pots of water and for burning things like rice because they can’t be turned down enough to simmer. […]

Stick Size: CO, PM2.5 and Thermal Efficiency

The diameter of sticks from the same species of wood (we use Douglas fir at ARC for testing) seems to have a dramatic effect on emissions and thermal efficiency. We used to use small diameter sticks of wood and experienced high thermal efficiency, low CO and high PM2.5. Small sticks make a lot of flame […]

ISO 19867: Thermal Efficiency

Boiling that five liters in 25 minutes max! There have been many versions of Water Boiling Tests, including the 1987 International Standards, Shell Foundation, IWA, ISO 19867, Chinese, Indian and many others. The lab tests do not predict in-field use but are intended to compare results when variables are controlled.  It can be amusing, in […]

What a Great Year!

Regional Testing and Knowledge Centers ARC just received a grant to hire full time assistance for the Regional Testing and Knowledge Centers (RTKC). Many of the RTKCs use our emission equipment. Jaden has just returned from Tanzania where she was setting up a new lab and Travis is going to Mozambique soon to do the […]

AI: Great but Stuck in a Box

It’s great to have colleagues whose opinions are trusted. Dr. Larry Winiarski was usually right, by which I mean, that when we built and tested his inventions they might not have been perfect but were significant improvements, good starting places for further development. I always appreciated talking to Dr. Tom Reed, inventor of the TLUD, […]

Cleaning up combustion: TOO COLD!

In the middle of August, we had three stoves under development using the three emission hoods (two-forced draft, one natural draft). Sam and Travis built the natural draft hood to help improve heating stoves. Sam is thinking about making another one, number four, since we are working on more heating stoves and things can get […]

Lowering Emissions in a Short, Natural Draft TLUD

Lowering Emissions in a Short, Natural Draft TLUD The great thing about 12” high tincanium natural draft TLUDs is that they are cheap, short and powerful. Dr. Tom Reed had a dream that a billion TLUDs would protect health, save wood, etc. We wondered if an all Tier 4, affordable, stainless steel ND-TLUD might help? […]

Learning From People

A rat proof box When Dr. Larry Winiarski and I lived for a season at Rancho San Nicolas in Baja California Sur, Mexico we wanted to be helpful. We built cook stoves, solar cookers and other delightful inventions that we found interesting. But Larry was an insightful fellow and he started to listen to folks […]

What’s Cooking at Aprovecho

Capacity Building with CSIR Over the past 3 years, thanks to three grants from Fire Capital, Aprovecho has been working with CSIR (Council for Scientific and Industrial Research) in Ghana to expand their lab capacity. We have focused on teaching stove design principles through co-developing a stove retrofit for boarding schools in Ghana. During the […]