How Nwoya residents turn farm waste into electricity

Residents and visitors tour the gasifier plant at Mandulis Energy Ltd at Gotngur Village, Purongo Subcounty in Nwoya District  PHOTO/TEDDY DOKOTHO

What you need to know:

  • The waste has led to the creation of a mini-grid with a power generation capacity of 32KW.

It only takes a resident to deliver their used up batteries and backups to a collection point from where they are conveyed to Mandulis Energy Ltd, a modern farm in Gotngur Village, Purongo Sub-county, Nwoya District.

More than 200 batteries are collected from about 150 homes in Gotngur and Paminolango villages and delivered to the farm for charging.

For members of a community struggling to meet their growing energy (electricity) needs while also lowering greenhouse gas (GHG) emissions, they have turned to one promising option, often overlooked by policy-makers, biogas gasification.

At the farm, locals collect agricultural (rice straws and husks) residues and deliver them to the farm to complement what the farm raises from its harvest. It is then converted into bioenergy for electricity.

The huge quantities of agricultural residues in this area are a big potential for energy generation, an alternative model of diversification, besides solar power.

Mr Peter BenHur Nyeko, the director of Mandulis Energy Ltd, says they constructed a mini-grid at Gotngur that generates approximately 32KW last year but it currently consumes only 20KW.

“We have a mini-grid with a generation capacity of 32KW from biomass gasification and we are now supplying electricity to the village at a free cost,” Mr Nyeko says.

According to him, another 20KW from solar energy was recently added to the mini-grid to bring the facility’s power storage capacity to about 120KW.

“The power in storage can supply more than 100 homes and an equal number of business units connected based on the model we are using,” Mr Nyeko says.

The farm has a value-addition unit with a rice mill that generates the rice husks, which are processed for feeding into the biomass gasification plant.

“The generated rice husk goes directly to the drier that accumulates it ready for use in a biomass gasifier plant,” Mr Nyeko says.

Here, biomass from agricultural processing waste is put into a gasifier that in turn produces three remarkable results, the char dust is used to produce briquettes, which is a cheaper cooking fuel for farmers.

While the gasifier turns this biomass into electricity for agricultural processing plants at the farm, a gas engine and generator is attached to this gasifier to produce its own electricity that is then supplied to communities.

Mr Raymond Lumansi, a technical manager at Mandulis Energy Ltd, says farmers bring their rice for milling after which the residue is kept for biogas gasification.

Others also ferry in husks and straws from their farms after harvest and deliver them to the facility.

In future, residents will be tasked to pay a subsidised fee to support the management of the facility.

“The 150 homes were connected in the first year to the mini-grid at zero cost but this will change in the coming future. When we begin to charge, a consumer will have to pay only $26 cents (aboutShs927) for every kWh to be able to access the electricity, which is the limit the regulator set,” Mr Lumasi says.

Every year, farmers in Nwoya create hundreds of thousands of tonnes of waste in form of rice husks. Purongo Sub-county alone produces more than one-third of the husk annually.

This bears an adverse impact on the environment since much of it is either burnt or dumped in fields.

Recently, Mr Nyeka says the farm introduced four vehicles that are being used in Gotngur to transport rechargeable batteries to the homes of people who are not directly connected to the mini-grid.  “This is done every three days and at no cost. The vehicles move cargo batteries to people’s homes so that they can get electricity,” he says.

Mr Nyeko says cooking gas is also generated from the plant, an intervention he argues will eliminate the use of firewood in the future.

“We will be able to cook food using a clean biogas stove using agricultural waste, the idea is that the entire ecosystem enables us to solve energy issues easily from productive energy to cooking as well as income generation,” he says.

Mr Geoffrey Ojok, the Paminolango Village chairperson, says hundreds of households are already benefitting from the intervention.

“Besides the electricity, wastes from our gardens that we previously burned or left to rot have been put to alternative use, those who deliver these wastes are paid,” Mr Ojok says.

Mr Emmanuel Orach, the district chairperson, says since the project started, there has been significant changes in the area that has prompted many people to flood into the area.

“There have been a big lack of electricity in these rural areas, they are yet to get connected to the national grid, and if we have such interventions, it is a big boost in enhancing the productivity of these communities,” Mr Orach says.

He says it helps them to eliminate agricultural wastes and hazardous disposal practices and turns agricultural waste into valuable ash to be used as fertilisers.

About the energy project 

The pilot project focuses on the use of Renewable Energy to Power Agriculture and Rural Livelihoods Enhancement (REPARLE) through the development of an off-grid electrification.

Led by Mandulis Energy Ltd with support from USAID’s Power Africa programme, it is on course to transform farming through the use of renewable energy to provide a rural farming communities with access to value addition for their crops and power solutions for households. Last week, the Department for International Trade, Uganda (DIT) in collaboration with Innovate UK hosted a team of UK energy experts for a trade mission in Uganda to seek partnerships with key Uganda energy companies to realise affordable and clean energy.

Daily Monitor established that the focus areas for the visit were next-generation solar technologies, smart green grids and mini and main grid-related technologies, energy storage, including batteries and mechanical storage, etc. The visit, according to Ms Tina Wamala, the British High Commission spokesperson, presented an opportunity for UK companies to work with Ugandan companies, researchers and innovators to tackle the challenges in clean, affordable and sustainable energy.

Dr Abiolak Oladiko, an energy expert with the London-based Tiwakiki Consults Ltd, said green energy is the way to go considering the current impact of climate change. “We can see the impact of climate change, there is prolonged drought leading to famine in some parts of the country while major rivers dry up. That means transitioning from traditional hydrocarbon energy into clean energy is the way forward,” he said.