Kwa Njenga primary school at the centre of an energy revolution

At the South East of Nairobi lies the sprawling Mukuru Kwa Njenga slum. Life here is fast-paced as boda boda riders, roasted maize hawkers, water vendors and food kiosks compete for
a share of the economy.

These roadside businesses operate from day break to nightfall when everyone flees to the safety of their shanties in fear of darkness.

The densely populated slum is beset by insecurity, poor sanitation and unmet power needs. However, one man is determined to change this. Mr. Amos Nguru is putting the final touches to a biogas unit that he has strategically located at the Kwa Njenga Primary School, deep in the heart of the slum.

Mr. Nguru, the Chief Executive Officer at Afrisol Energy Ltd and his men have been working on the project since April and are set to generate off-grid power in January 2015.

Mr. Nguru explains that his simple bio-digester unit was born out of the desire to use locally available materials for off-grid power solutions. In the Mukuru Kwa Njenga slum, the biggest problem is sanitation and toilets are such a big burden; he says.

“Bio-digester manages waste in a sustainable manner to give both hygiene and energy. It is the future of power and sanitation in high density slums in Kenya and by extension, Africa,” he says.

Afrisol Energy Ltd has been operational since October, 2010 and specialises in biogas system installations and consultancy in biogas generation. The 15KW electricity Afrisol project at Kwa Njenga primary
school is a beneficiary of the Power Africa Off Grid Competition.

General Electric (GE) teamed up with the US Africa Development Foundation (USADF) to launch this competition in 2013 in order to address the energy needs of marginalized communities in Africa who are not reached by the national grid.

Mr. Nguru is one of the competition winners and his project is the recipient of a $100,000 (Sh8.8 million) grant from USADF.

With the financing, Mr. Nguru has been able to implement the biodigester project development, right from planning and design of the system, community mobilisation and the actual construction of the biodigester system. “We have done the excavation and the construction of the toilets (waste-collection chamber),” he explains.

He is awaiting the importation of the biogas generators from China, which will cost $5,000 (Sh445,000).

Once the generators are here in the next two weeks, Mr. Nguru will oversee the installation of the high-mast flood lights and the general electrical works for the distribution of power in the school.

The project too has provided direct jobs to a minimum of five people who are always on site. “In addition, we regularly employ as many as 30 young men who work on the project from time to time,” Mr. Nguru says.

The 15 KW of power will be shared between the school and the neighbouring community. “A high mast of flood lights will be erected at the school compound and this will light up the slum and its dark alleys in all directions,” states Mr. Nguru.

This will help to arrest insecurity in the slum. Kwa Njenga primary school is connected to the grid, but the power is unreliable due to vandalism of the connection lines that pass through the slum. “At times, it takes over a month for the problem to be fixed,” Mr. Nguru says.

The neighbouring community frequently taps the school’s power lines through illegal connections, states Mrs. Deborah Mwandagina – one of the three deputy headteachers at the school.

This sees the school’s administration struggle to pay for high power bills, for electricity that they least use. As such, green power from the biogas unit will offer some relief. It will light up the school and restore back to operation some of their unused computers due to power deficiencies.

Mrs. Mwandagina explains that all their 1,800 pupils come from disadvantaged households in the locality and thus benefit greatly from the daily free lunch at school.

“For some, it could be their only meal for the day,” she says. However, the high cost of fuel-wood and its limited supply is a challenge to the school. “Cooking for the vast population consumes a lot of firewood, which is hardly available in Nairobi and this makes it even costly,” Mrs. Mwandagina explains.

Thus, the school has very high expectations that the bio-digester will deliver sufficient gas for their cooking needs.

Kwa Njenga Primary School is indeed set to reap big not only through power connectivity, but also improved sanitation. Mr. Nguru and his team have put up new toilets in the school compound, which they intend to use as the waste collection chamber.

There is a shortage of toilets in the school as eight of the boys’ toilets are unusable due to a blocked sewer. The older girls are also making do with a pit-latrine. “I would love to see our children in class when it is class-time, but not in the toilets,” shares the deputy headteacher. This will also see better time management for the school. The pupils will make use of the toilets

The biogas project has introduced water points in the school with in-built sinks in the toilets, where children will wash their hands. The used water from the sinks will be recycled, as it will be dripping to the urinal and the toilets, while the overflow will go to a storage tank.

The project too, has given exposure to the student population at Kwa Njenga primary school – who mainly emanate from the slum that there is good life out there, if only they work harder.

“Most of them hardly know that there are flushing toilets, and they have never used sinks before. This, is a big motivation to them that there is a better life,” Mrs Mwandagina explains.

With the provision of enough fuel for lighting, cooking, improved sanitation and security in the school and the community, the many challenges at Kwa Njenga Primary School will be halved.

The biodigester will not just be powered by human waste, as Mr. Nguru is considering tapping into organic waste from the neighbouring community.

The outside of the toilets houses the waste storage chamber, where the pupils will deliver organic waste from their homes. “The waste will be sorted out so that we only use the organic compounds that can decompose,” Mr. Nguru says. This will further ensure hygiene and sanitation is maintained in the vast Kwa Njenga slum, which has got no proper structures for waste management and disposal.

Given the perennial water shortage problems in Kwa Njenga, Mr. Nguru has designed the toilets in a way that they will utilise as little water as possible, while still maintaining hygiene. “They will all be flushing from a common point,” he says.

The facility will also make use of harvested rainwater. The bio-digester has the potential to arrest the problem of insecurity on a wider- scale. “If I am to replicate this unit in the slum, I will also make use of around
the clock digital surveillance system,” he says.

This will help a lot in arresting insecurity because, everyone, including notorious criminals will have to make use of a toilet, he adds.

The system will require some little money for maintenance. Mr. Nguru is counting on the production of the organic fertilizer to raise some income to a point where the unit is self-sustaining. He intends to use UV rays from the sun to process organic fertilizer from the solid remains in the expansion chamber. “The solids will be picked and processed into granules,” he says.

Mr. Nguru’s innovative bio-digester technology is an effective solution that both creates value and addresses climate change issues. The technology has the capacity to produce refined, non-chemical fertiliser, clean and cheaper energy.

This significantly reduces greenhouse gas emissions and limits deforestation by minimising the need for wood fuel.