To promote renewable energy as a cost-effective technology in a world facing the impact of climate change and global warming, the University of South Africa, diversified miner Exxaro Resources and the South African National Energy Development Institute launched the first institutional anaerobic digester at nonprofit organisation EARTH Centre’s premises, in Johannesburg.

Making use of a sustainable water supply, including grey water, the anaerobic digesters will be used as a source of fuel for cooking in households, schools and community organisations, and will not only vastly improve people’s standard of living but also help the environment by minimising organic waste.

The digestate can also be used as a source of biofertiliser.

The digester at the EARTH Centre, in particular, uses horse manure as a feedstock.

The project is also able to create employment, help mitigate climate-change- related challenges, improve the living standards of beneficiaries, facilitate sustainable waste management, enhance the transfer of skills and knowledge and stimulate an interest in renewable energy.

A 10 m3 digester was successfully installed in June at the EARTH Centre, which provides holistic therapy for disabled children through programmes with horses. The digester has been running trouble-free for three months.

With the successful installation of the first institutional digester in Gauteng, 19 more are in the pipeline, to be installed at a variety of locations, with particular focus on institutions such as old-age homes, early childhood development centres, schools and clinics.

This focus on institutions, Working for Energy GM David Mahuma tells Engineering News, was motivated by the higher ratio of people who can benefit from one such system at an institution.

This was not to say that digesters would not be installed at households, he adds; these will only be on a smaller scale and in areas where a need has been identified.

Before installations were done, Mahuma explains to Engineering News, feasibility studies were conducted to ensure that there was a sustainable environment and water source, as well as a need for the digesters.

He was unable to provide a timeline for the remainder of the institutional installations, saying that it would be dependent on where the demand and needs were identified, as well as the result of the feasibility studies.

“In line with our mandate to be an enabler for South Africa to take full advantage of our abundant energy resources, we look forward to more strategic collaborations, which will see more communities being introduced to sustainable and clean-energy solutions,” Mahuma said.