Sunken pot, 50% thermal efficiency cook stove with chimney
When (oh, when!) will PM2.5 be included in carbon offset methodologies?
Who can blame stove manufacturers for selling high thermal efficiency/low combustion efficiency stoves when protecting health is not financially rewarded?
Factories can only sell what the market demands even when they manufacture better stoves. Manufacturers, like SSM, already have slightly more expensive, much cleaner burning stoves ready to go.
Including PM2.5 in carbon revenue might go a long way to help projects pay for higher combustion efficiency stoves.
PM 2.5 needs to be reduced by ~ 90% to protect health in kitchens with 15 air exchanges per hour. The needed % reduction is halved when air exchange rates are doubled. This may be the most cost effective way to protect health? Cooking outdoors with an estimated 60 air exchange rates per hour is very effective in reducing exposure.When cooking inside, perhaps a durable stove with improved combustion efficiency and a chimney would help the large percentage of cooks who, for many reasons, continue to cook with biomass?
https://aprovecho.org/wp-content/uploads/2024/09/sunken-pot-cad.jpg630438Kim Stillhttps://aprovecho.org/wp-content/uploads/2015/11/Aprovecho-Logo.pngKim Still2024-09-06 15:46:042024-09-06 16:04:40Increased Air Exchange Rate Protects Health
Using the ISO testing protocols, Champion (2021)* reported energy emission factors (g/MJ) from the Three Stone Fire, a forced draft Pellet Stove, a forced draft Wood Fan stove, a natural draft Rocket stove and a charcoal stove. ARC added results from a Jet-Flame stove. Using the estimates of global warming potential from the Gold Standard 2017 Methodology** we started to develop a feeling for how various stoves might address climate change.
The calculations suggest that the Three Stone Fire could be a lot worse for climate when Black Carbon and short-term climate forcers are included in offset calculations. At the same time, forced draft stoves appear to have the potential to generate increased emissions reductions (and higher carbon revenues).
*Champion, Wyatt M., et al. “Cookstove Emissions and Performance Evaluation Using a New ISO Protocol and Comparison of Results with Previous Test Protocols.” Environmental Science & Technology, 2021, 55, (22), 15333-15342. DOI: 10.1021/acs.est.1c03390
Unfortunately, although introductions to lab tests warn that results do not predict actual performance, the recent use of lab data to earn carbon credits has made an unfortunate error more commonplace. For decades, introductions to lab tests have warned that only field-testing can determine actual efficiency, emissions, effectiveness, market validity, etc. The World Health Organization based their stove standards aimed at protecting health on field-testing for this reason.
Lab tests are helpful when comparing performance to understand how fire might be more useful.Starting with the 1985 International Standards, test users were advised not to use lab data to predict actual performance. While improving other carbon methodologies, using field-testing to estimate reductions would dramatically improve the accuracy of offsets.
Carefully performed lab tests tend to overestimate fuel efficiency and underestimate emissions. This has landed cook stoves and heating stoves in serious controversy. A lab tested Tier 4 cookstove can be Tier 2 in real life – or mistaken for a flowerpot. My first Rocket stoves were often used for this important function in Mexico.
A lab tested 2 g/hr PM heating stove often emits a lot more smoke when the harmful pollutant is measured from chimneys in houses. In an effort to reduce confounding variables, lab tests show closer to optimal performance. Real life human beings tend to operate stoves with less care, wood is wet, life deserves attention, too.
Maybe the test warnings should have been highlighted in green?
International Standards, 1985
“This is a laboratory test…while it does not necessarily correlate to actual stove performance, when cooking food, it facilitates the comparison of stoves under controlled conditions with relatively few cultural variations.” (Testing the Efficiency of Wood Burning Cookstoves, International Standards 1985).
(ISO 19867-1)
“This document provides a standard test sequence that can be used to compare the performance of various cookstove types, cookstove fuels, and cooking practices under controlled laboratory test conditions, as specified in this document. For evaluation of the performance and predicted outcomes of a cooking system in the field [comprising cookstove(s), fuel(s), cooking vessel(s), kitchen, ventilation, and user(s)], ISO 198691 applies.”
The British Petroleum clean burning Oorja FD-TLUD stove from India
If protecting health and climate are important in stove projects, why not monetize the reductions of health/climate pollutants in carbon-offset projects?
Only the reduction in fuel use earns carbon income now!
With equal heat transfer efficiency, dirty burning stoves earn as much as clean burning stoves.
Dirty burning stoves are less expensive. “Market demand” reinforces the use of biomass stoves with low combustion efficiency.
Why not add income from reductions in CO, PM2.5 and Black Carbon, etc. to carbon projects to get cleaner burning stoves into use?
