Past, Present and Future

After handing in a bachelor’s thesis in 2007, Prof. Joaquin Perez Diaz had a chat with Vianney and the story of generating biogas from waste came up. So we began to investigate how energy from organic waste was to be produced. We end up by experimenting with cow dung and a few selected organic waste in plastic bottles. This research lasted a 15 months. We managed to publish part of the results. We also had our 1st Generation biogas digester.


Between 2009 – 2010, William Woche, Emma Casson and I were on another interesting experiment. Biogas from a mixture of Chimpanzee poop and food waste. We also experimented making briquettes from waste. Biogas from Chimp poop was a tough job and challenging, however, it was fun. We went out to Ngamba Island on a couple of weekends after going over the design of the digester proto type. This was our 2nd generation digester. A trip to ARTI India was a great and memorable, we learnt a big deal about different digester designs and briquette making. It was after this trip that we were able to produce enough BIOGAS which cooked the first meal at Justice’s home! It was a SUPER day we will never forget.

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Established in 2011, Green Heat is a social enterprise determined to transform waste into energy helping the country to eradicate the over dependence on wood-fuel. The growing renewable energy company is based in Kampala, Uganda with a primary focus on converting waste products into biofuel; the company’s expertise is in biogas and briquette production. Biogas is the syngas produced from the breakdown of organic matter in the absence of oxygen. Briquettes are a clean fuel alternative to charcoal using dried banana peelings and charcoal dust (a waste char product). Green Heats products provides high quality, reliable and long-term sources of sustainable cooking and lighting energy for local communities. Green Heat is aiming to upscale its briquette production to meet local demands while continuing to increase its expertise in biogas. The company is looking to build upon its well established position in the renewable market, to expand into the national general energy sector with aspirations to be the partner of choice for green energy products and services in Uganda.

Digester location and educational illustrations


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Developing the logo  

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Future work with Afri-Flame Network: “The Potential of Small Scale Biogas Digesters to Alleviate Poverty and Improve Long Term Sustainability of Ecosystem Services in Sub-Saharan Africa”

Main project features: This proposed action focuses on improving the efficacy of energy production by small-scale biogas digesters and biomass stoves in rural households in SSA. The aim is to integrate energy production within the whole farm system to reduce biomass energy consumption, improve rural livelihoods, increase productivity of soil, crops and other diversified farm outputs as well as improving the health of families through reduction in indoor air pollution.

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Activities performed: Three pilot projects for each of the three digester designs will be set up in three selected villages located in Ethiopia, Uganda and Cameroon. A further three pilot projects in each country will use the significantly cheaper option of improved efficiency cook-stoves. In addition, a controlled trial will be set-up for each of the digester types and for improve efficiency cookstoves in each country. The processes of installation design will be formalised to include environmental, financial and technical factors. The flow of finance, pathogens, carbon, nutrients, energy and water will be quantified and compared to baseline data obtained before each pilot was established. Changes in household air quality will also be measured. Key loss processes will be identified and changes to the established practices to reduce inefficiencies will be proposed.

In the 18th month of my PhD in Environmental Sustainability at the University of Aberdeen. This paved way for Gabriel Okello and team to take charge of the innovations at Green Heat. Gabriel is an Environmental Chemical Engineer. 


Finally, we thank our esteemed clients, Green Heat team, friends and Family. Without you watching our backs we would never improve.  




Biogas Appliances

Biogas stoves are made in two parts: the burner itself, which mixes gas and air and feeds it to the flame ports, where it burns; and the frame within which it sits, which uses the flame to heat cooking pots or to generate light or use the heat in some other way. The frame for a stove supports the burner on legs and holds cooking pots the right distance away from the flame for effective heating. See the images below, look out for the frame (in red) and the burner.

The amount of gas that flows into the burner is controlled by the jet, a hole which is carefully sized. The air and biogas are mixed and fed to a ‘manifold’ which feeds the flame ports, where it burns. The burner ports are drilled into a shaped cap, which can be removed for cleaning if food is spilled into the burner ports.

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