Smell the Coffee, Not the Smoke: Biochar Stoves on Coffee Farms in Central America

Good coffee and great biochar are a match made in heaven. Especially since one product of that match is a cleaner cook stove for migrant coffee pickers who often have only open fires for cooking.

Biochar in use in a field.

Cooking on an open fire in a migrant coffee picker camp. Photo courtesy of Art Donnelly.

students and stoves

Santos Tour’s Australian students, with some of the TLUDs built during a one-day stove workshop in Providencia CR. (Art Donnelly in orange t-shirt).

cooking dinner

The Estufa Finca cooks dinner.

char yield

After the wood gasifies, biochar is left.

Future “estufa” builders of APORTES

The match started in Seattle, a global center of coffee consumption and home of the Seattle Biochar Working Group. SeaChar (as it is known) is barely one year old, but this biochar regional group has a huge stack of accomplishments already. Last summer, SeaChar brought in TLUD (Top-Lit UpDraft) gasifier stove expert Paul Anderson to give a stove making workshop. That inspired SeaChar member Scott Eaton to pack his tin snips down to Nicaragua and start building stoves for people who were still cooking over smoky open fires.

SeaChar co-founder and metal sculptor Art Donnelly was also badly bitten by the TLUD bug. He began making elegant TLUD stoves with artistic scrolls and whimsical touches like an air controller made from an Altoids mint can. Showing off his stoves at a Seattle garden fair, Art met Arturo Segura, owner of Sol Colibri, a sustainable, shade grown, organic coffee farm in the Santos region of Costa Rica. Segura is also a direct trade sales rep for La Alianza, an alliance of organic producers of coffee, cocoa, and bananas. Arturo Segura was interested in making biochar on his coffee plantation and he also wanted to help the migrant coffee pickers from Panama and Nicaragua who live with very little resources in difficult conditions during the picking season. Poor indoor air quality associated with cooking on an open fire is a major cause of respiratory disease.

In January, Art traveled to Arturo’s farm in Santa Maria de Dota, Costa Rica. What followed was an intense two weeks of interviews with pickers, demonstrations for farmers, and scrounging the countryside to see what stove making materials were available locally. The result was another elegant Art Donnelly design – the Estufa Finca (farm stove).

TLUDs use two nesting cylinders with a gap between them. Art discovered that readily available corrugated roofing tin made a perfect outer cylinder with built in gap spacing. With the help of Santos Tours, a local eco-tourism company, a group of Australian students visiting the region was recruited to help construct the stoves and in one long day they made 15 new TLUDs. The coffee pickers on Arturo’s farm tested the stoves and were pleased with how they made cooking meals easier and cleaner. The pyrolytic gasification process converted about 40 percent by volume of the cooking fuel (wood scraps) into biochar.

Arturo Segura and other organic coffee farmers in the region are already heavy users of a biochar-bokashi mix. They ferment the waste coffee berry meat with bokashi organisms and mix that with charcoal to produce a superior fertilizer. Unfortunately, the charcoal is getting more expensive to buy and Segura does not like the destructive methods used to make it – whole trees are cut down, placed into pits, covered with damp earth and left to smolder for a week. Low biochar yield, air pollution, and forest destruction are the results. The biochar produced by the pickers Estufa Finca stoves could provide a significant source of free, sustainably produced biochar to the growers.

Art Donnelly’s stoves were a hit, and he is now preparing for a return trip to pave the way for a larger project with many partners. One essential partner is a group of local women entrepreneurs. Forming under the umbrella of a rural development association: APORTES (Association of Small Organic Farmers and Eco Educative Rural Community Tourism of the Santos Region) they want to set up a woman-owned co-operative to produce stoves and stove kits. As one of their members pointed out after seeing an Estufa Finca stove demonstration: the potential market in the region is in the millions. When Art returns to Costa Rica in April, with finalized and emissions tested prototypes, he will be training stove builders and helping to outfit the stove factory workshop.

Other items on the agenda for the April trip include recruiting households to participate in field tests of stove emissions and cooking efficiency. Art hopes to cement relationships with several international aid groups that have shown an interest in supporting the project. Student helpers will continue to be an important part of this project and Art hopes to get everything ready for a group from Educators Without Borders to come in July to help build stoves.

Art is also busy involving universities, both the National University in Costa Rica and California State University at Humboldt, where graduate students at the Schatz Energy Research Center will help test and engineer improvements to the Estufa Finca.

The farmers of La Alianza and SeaChar members have been using their own money to make this much needed work happen. But as a new organization, SeaChar does not have funds to support the Costa Rica project. “We are asking for seed money to support travel and training and to buy materials and tools,” Donnelly said. “We have a handy donation link up on the SeaChar website at”

SeaChar is also asking for donations of tools that Art can take to Costa Rica with him in April. Tin snips, pop-rivet guns, small sheet metal working tools, electric drills, and drill bits would all be very useful.

Contact Art directly if you have tools to donate, or for more information. His email address is:

Written by Kelpie Wilson and posted on the IBI site: