Cooking outside When the air exchange rate is doubled, the concentration of smoke is reduced by half. The average house in low middle income countries is estimated to have around 12 air exchanges per hour (ISO 19867-3). When ARC measured the air exchange rate outdoors in a gentle breeze it was found to be about […]
There are at least three ways to make institutional stoves with chimneys, all of which work well and save fuel and decrease emissions. Here they are: Shell Foundation supported the making of an eight-part video, a step by step guide to making a 50 to 100 liter institutional Rocket stove, with a heat resistant metal […]
by Kirk Harris Blade cross sectional shapes: There are several main physical principles that can be used to make a functional cross-sectional shape. The gas enters the stationary fan vertically from below, and should leave the fan at as flat an angle as possible. Deflection: The side of the blade that faces the oncoming gas […]
learnmech.com/importance-of-turbulence-swirl-squish-tumble-related-to-ci-engine Turbulence is very important for close to complete combustion. Swirl, Squish, and Tumble are used to create turbulence in internal combustion engines. Kirk Harris discovered that a static fan shape with overlapping 70 degree blades creates lots of fast moving swirl at the approximately one to two meter per second velocities found in TLUDs. […]
In the last Newsletter, we announced the publication of Aprovecho’s recent research on the Jet-Flame, “Retrofitting stoves with forced jets of primary air improves speed, emissions, and efficiency: Evidence from six types of biomass cookstoves” Here is a simplified summary of the findings: When the goals for biomass cook stove interventions were raised to include protecting […]
The Journal “Energy for Sustainable Development” has just published Aprovecho’s most recent research paper, “Retrofitting stoves with forced jets of primary air improves speed, emissions, and efficiency: Evidence from six types of biomass cook stoves.” It was authored by Samuel Bentson, David Evitt, Dean Still, Dr. Daniel Lieberman and Dr. Nordica MacCarty (Energy for Sustainable Development 71 […]
The Rocket stove requires forced draft to create sufficient mixing in the flame to achieve Tier 4 for PM2.5. In addition, when sticks are pushed too fast into the Rocket, too much wood gas enters the combustion zone and a lot of smoke is emitted. Metering of the fuel is necessary to keep the Rocket […]
Before starting to develop cleaner burning cook stoves in the 2013-2015 DOE project, ARC researchers completed a survey of best performing existing stoves. Improving combustion efficiency to protect health (and climate) has continued as various cook stove organizations have worked tirelessly to meet the WHO 2015 PM2.5 Intermediate Emission Rate Target of 1.75mg/minute, calculated to […]
How can smoke, extremely dangerous for health and climate change, be ignored in carbon credit equations? Carbon dioxide and methane are counted but not smoke. Carbon dioxide is reduced when heat transfer is improved resulting in less wood being burned. Wood doesn’t make appreciable amounts of methane. Because smoke is not counted to earn carbon […]
The investigation of how to reduce emissions and fuel use in biomass stoves continued with support from an EPA SBIR award. Two products were manufactured by our Chinese partner SSM, a heating/cooking stove and the Jet-Flame, a $12 insert that has made stoves 67% cleaner burning in field tests. https://www.jet-flame.com/ The Gates funded Global Health Labs […]