Plans to construct an 800m3 bio-digester in Mbare are at an advanced stage. City of Harare (CoH) has already received the €300,000 ($411,000) donation from the European Union which will be used to construct the digester. The Mbare community has been consulted and has pledged their full support for the project.

The bio-digester is a bid to utilise the vegetable waste at Mbare Musika, the country’s top vegetable market (see Big and Bustling: Mbare Musika), which attracts farmers from all corners of the country.

CoH acting environmental regulatory planner Clifford Muzofa explains, “We are just waiting for the construction tender to be awarded and then for the rains to recede so we can start digging.” Muzofa said they expect to start construction mid-March or early April if the State Procurement Board is quick in awarding the tender. “We are going to make it a point that whoever wins the tender is going to employ the general labourers from the community so that they may also benefit financially.”

When complete, the bio-digester will significantly reduce the cost of taking waste to Pomona dumpsite. “Though we will mainly be taking in agricultural waste, we have engaged the Mbare community to bring their household waste, which we will screen to take the biomass.” Paper and plastic will be separated from other waste to be sold to recycling companies.

Muzofa said, “As part of the project we will be buying a 100 kilovolt generator which will be generating  electricity to be fed into the ZESA supplies.” There will be a team of specialists monitoring the plant at all times so that power generation is maximized and any changes are quickly observed.

With the local community bringing in their waste there will be a reduction in breeding grounds for diseases including cholera and typhoid. As an added benefit, Muzofa revealed, “We are also going to make life easier for the community by installing heated showers which the public will use for a small fee.”

Farmers who contribute their residue will be given organic fertiliser that will be produced at the plant. The bio digester is expected to be fully functional by year end.

The Mbare bio-digester is not the first in the city as the Rural Electrification Agency (REA) has already constructed plants at Harare Hospital and Roosevelt Girls School. CoH plans to establish more bio-digesters in different communities depending on the success of the Mbare project. This would mean an increase in electricity generation.

Bio-digesters are increasingly popular around the world. Nigeria’s African Women and Rural Environment (AWARE) has established digesters in different communities, benefiting the environment as well as the economic well being of over 500 rural women. Another initiative is the Mumbai Women Bio-digester Project in India. In Mumbai approximately 3,000 tons of organic waste is produced daily, generating a lot of greenhouse gas into the atmosphere. The project has seen CoLab partner with Stree Mukti Sanghatana (SMS), a women’s liberation organisation that uses the Nisargruna bio-digester technology to generates biogas and high-grade fertiliser, to create jobs for women waste pickers. These have changed lives in one of the poorest communities.