GreenHeat, Uganda

Triple-wins for African biodigesters

Green Heat has created an on-farm system that produces biogas and fertilizer while reducing the demand for water by 80%

On-farm biodigesters – devices where organic waste matter is broken down by bacteria to produce burnable biogas – have been promoted widely throughout Africa as well as other parts of the world. One of the most significant caveats to keeping them running is their need for water. Green Heat, a Ugandan company, has found out how to address this challenge through its patented Slurry-Separation Technology (SST). The Green Heat biodigesters can be fed a range of wastes, including animal manure, human waste and decaying plant matter. The biodigesters can also be fed with a variety of liquids such as rainwater, wastewater, and even urine. Green Heat’s SST separates water from waste matter, recycling water by-products back into the system. This process reduces the demand for water by 80% and cuts time-consuming water collection dramatically. The SST dewaters slurry (waste) and converts it to solid fertilizer. This dry fertilizer can then be applied directly to the farmers’ fields. According to Green Heat, the dry fertilizer has boosted crop yields up to 270%.