By Hazvinei Mwanaka
Many rural communities in Zimbabwe are living in extreme poverty and are relying on firewood for cooking and heating. Few have access to reliable sources of energy such as solar or biogas which are clean and environmentally friendly.
“I have little knowledge about renewable energy sources. I know little about solar which my neighbour uses. I envy her and my life would be a lot better but with my current economic situation I cannot afford it,” said Maria Sendu from Mushandike village in Zimbabwe’s southern province of Masvingo.
Maria, a single mother of two, says she struggles to feed and pay school fees for her three children and and accessing renewable energy at her home is way behind her economic means.
“I sell vegetables and on a good day I can get $3 dollars, but some days I do not even get anything and from that amount how can I purchase something of any value apart from living from hand to mouth,” she said.
Many people in rural areas are not aware of biogas technology and how it works.
“I only heard about biogas at a community meeting that was done here and honestly I did not understand most of the things that were said.
“I would actually like to have one (biogas digester) since I still remember that it can last for over 20 years. So if I can purchase one I know it’s a lifetime investment,” added Maria.
However, as is the case with several people surviving on subsistence farming in rural areas, installing one biogas digester is just but a dream.
Renewable Energy Expert and Principal Energy Development Officer in the Ministry of Energy and Power Development, Blessing Jonga, said the amount needed for one to set up a biogas digester varies with the availability of some local materials.
“Cost varies between US$750 – US$1200 for biogas digesters of sizes between 4m3 – 9m3. It can be more for sizes greater than 9m3 but less than 20m3. Availability of some local materials such as bricks, concrete stone, river sand and pitsand, also have an impact on the cost in the sense that some households can get such materials for free in the rural areas.
“The price for biogas digester construction is a once off payment with just minor maintenance once in a while. The life span of a biogas digester system is more than 25yrs and there is no significant cost linked to its operation,” said Jonga.
He said that biogas is a sustainable and clean source of energy compared to firewood adding that besides energy provision, one also gets bio-slurry (a rich organic fertiliser) from the technology which can be used to replace expensive inorganic fertilisers.
According to Jonga between 2012 to date, more than 250 domestic biogas digesters have been constructed in rural areas by builders who were trained by government and some NGOs.
“There are also more than 50 institutional digesters constructed by government at institutions like boarding schools, hospitals, prisons and farms. Government is working with some NGOs in building capacity within the country through training builders on how to construct digesters and promoting the technology through awareness raising,” he said.
A biogas-digester causes organic waste such as human excreta, animal dung, vegetable waste or kitchen residue to ferment in anaerobic conditions to produce inflammable gas and organic manure as a by-product.
It contains large amounts of methane gas which can be used directly for heating, cooking and lighting.