Entries by Kim Still

Learning from the Three Stone Fire

Use of traditional three stone fire in one Rakhine village.  ©FAO/Myanmar As with any tool, the skill of the operator determines how well the work is accomplished. It takes years to learn how to use a hammer or shovel. The Three Stone Fire can be effective and clean or it can be very dirty and […]

Turn Down Ratio and Firepower in 18 Stoves

Firepower and turn-down ratio of 18 stoves, from “Test Results of Cook Stove Performance” The ARC/EPA 2011 book “Test Results of Cook Stove Performance” compares performance and emissions, including turn down ratio and firepower, from survey of 18 stoves. Firepower is a measure of how much energy is released per unit of time. More energy […]


Investigating the Chitetezo Mbaula Cookstove

Read more about the Chitetezo Mbaula project at unsustainablemagazine.com. Photo by Deogracias Benjamin Kalima The Chitetezo Mbaula cookstove is distributed by United Purpose in Malawi with the goal of combating deforestation by replacing the traditional charcoal/firewood cooking stoves. In an effort to assist, ARC worked with stakeholders to see how small changes in the stove might […]

Health and Emission Rates of PM2.5

photo by urbanfeel on flickr Several articles have pointed out that using biomass-heating stoves can result in health problems in densely populated areas. We are working with friends at the EPA to think about how we might define PM2.5 emission rates for residential biomass heating stoves that would protect health in densely populated cities.  When the […]

Exploring Horizontal Gasifiers

What happens if a bunch of sticks are bundled together, lit at the tips, and inserted into a well-insulated horizontal enclosure that enters a Rocket stove providing draft? Well, it’s hard to get everything to work well. As Dr. Winiarsky pointed out “Gasifiers are finicky.” But, when all of the tips of the bundle of […]

Shipping and Climate Change

Balthazar Schulte, Lyttleton Harbor, New Zealand I recently read a Time article that pointed out that shipping accounts for 2.2% of annual global greenhouse gas emissions. To put it in perspective the writer, Aryn Baker, suggests that if shipping was a country, it would be the sixth largest CO2 emitter in the world, on par […]


Natural Gas, Methane and Nitrogen Oxides

I didn’t realize that natural gas is mostly methane which is about 84 times worse for climate change compared to CO2. As reported in the recently published study “Methane and NOx Emissions from Natural Gas Stoves, Cooktops, and Ovens in Residential Homes,” methane leaks are bad news for both environmental and personal health. (Lebel, et al, […]

Climate Change: Replacing Natural Gas and Coal Burning in the USA

Could biomass energy reduce the increased demand on electricity for home heating? Could the clean burning of biomass make a greater percentage of electricity partially replacing coal and natural gas, powerful climate forcers? Source: www.eia.gov/energyexplained/electricity/electricity-in-the-us As seen above, renewable energy now makes 20% of the electricity generated in the USA. Residential and commercial energy use makes […]

Tuning A Stove With Real Time Data

PM2.5, CO2, CO and other metrics measured by the LEMS are displayed in a real-time graph during testing. When enough data is available in real time, it is not hard to make progress improving a stove. The LEMS emission hood provides real time, holistic feedback as the experimenter makes changes. Watching all of the measures […]