Lake Tana: Turning Water Hyacinth into Home Energy ^{CEFR B2}

In recent years Lake Tana’s fishermen have struggled as invasive water hyacinth spread across large areas, blocking boats, damaging nets and driving fish away from traditional fishing grounds. In Shehagomngie village, Gondar Zuriya district, residents found that hand removal was tiring and ineffective because the plant quickly returned.

Assistant professor Yezbie Kassa and colleagues tested a small-scale biogas approach. They collected water hyacinth and animal dung, fed both into anaerobic digesters, and over several weeks the organic matter broke down to produce biogas, primarily methane and carbon dioxide. The remaining bioslurry became a nutrient-rich fertiliser. Kassa noted that decaying hyacinth releases an oily substance and that the plant yields a higher volume of biogas with a higher methane concentration and fewer harmful gases than many other materials.

The pilot was installed in just five households. An early volunteer, fisherman Fentie Wabi, said his family now uses the gas for cooking and lighting instead of firewood, and that applying bioslurry raised maize and vegetable yields while cutting spending on chemical fertilisers. Villagers were sceptical at first, but seeing lights and smelling the cooking gas changed minds and reduced time women spent collecting wood.

Experts such as Getachew Sime Feyissa say turning invasive plants into biogas, biofertiliser or other products can reduce environmental damage and create livelihoods. Scaling up faces hurdles: it needs stronger government support, funding and policy backing, and expansion is made costly by security problems in rural conflict zones, rising construction costs and the need for imported materials. Kassa urged subsidies and cooperative organisation to help more families adopt the technology.