A few years ago, on another series of hot summer days, Aprovecho hosted a seminar on biochar. About twenty enthusiasts from all over the US joined us for a biochar summer camp, lighting a lot of stoves and scaring the safety advisors. We needed more spark screens. At the closing event, we created a list […]
Following the COP26 international climate conference, Senator Susan Collins (R-ME) and Senator Dick Durbin (D-IL), have introduced a bill to accelerate access to clean cooking. Here is the opening text of the section defining the activities directed in the bill. H.R.6316 has been referred to the Subcommittee on Energy: SEC. 5. CLEAN COOKING PROGRAM. (a) Department Of […]
The Problem with Metal It’s great to start making stoves and testing ideas with tincanium (cut up tin cans). Making new prototypes from tin cans is a quick, inexpensive way to start the design process but tin cans only last for a limited amount of time, depending on the temperature of the combustion chamber. At […]
Written decades ago, the lab based tests for both biomass heating and cooking stoves were designed to achieve statistical validity by controlling variables. Because many real world variables were removed from the heating and cooking stove protocols, the results were known not to predict real world performance. Automobiles are currently tested on a dynamometer instead […]
For good thermal efficiency, be sure that as much heat as possible is being transferred to the outside of the cooking pot. The temperature of the hot gas flowing past the surface of the pot is increased by 1.) Creating as much flame (1,100C) as possible in a low mass, insulated combustion chamber 2.) Decreasing […]
“Lightweight walls have the intrinsic potential for much higher performance than massive walls due to their lower thermal inertia.” –Baldwin, Biomass Stoves: Engineering Design, Development, and Dissemination, 1987 After about 80 minutes, the earthen mass wall in the illustration above gets hot enough to equal the heat loss in a single metal wall. After about […]
Yesterday, two fine fellows who manufacture stoves in southern Oregon visited our lab. One of the very competent guys had just installed a Corvette engine in a Jaguar, for fun. We quickly got on the same page when the ARC staff showed them how an emission hood (with both real time and gravimetric measurements) enables […]
Watching a Rocket stove or a pellet stove (as above), it becomes obvious that metering the fuel is a primary factor in achieving close to complete combustion. When too much fuel is introduced into the combustion chamber, the emissions of smoke increase almost immediately. For the clean burning of biomass, the controlled metering of fuel […]
We have been having a lot of fun doing a modern literature search: Surfing YouTube. YouTube is often years ahead of the slower, but probably more accurate, information in peer reviewed journal articles. I suppose that many people are looking at both. A shared misunderstanding seems to be that making the combustion zone hotter cleans […]
Transitioning to carbon neutral electric generation would replace a big climate problem in the U.S., since about 60% of its electricity comes from burning natural gas. The World Energy Forum forecasts that around 40% of electricity could be from wind and solar doing most of the heavy lifting by 2040, enabling a net zero global […]