Students and teachers at Kasiisi nursery and primary school in Uganda have found an innovative way to save money and protect the planet when nature calls – by building a biogas digester that allows them to harness the energy contained in human faeces.



The thought of it is enough to put most people off their food, but the plan is to produce enough methane to cook meals for the school lunch programme, which provides rural schoolchildren living near the Kibale national park with a meal every day. A large brick-lined vessel was installed in a pit beneath the latrine. Here, the waste is mixed with cow dung to aid the process of breaking down the organic materials into methane, carbon dioxide gas and nutrient rich fertiliser.



The children at Kasiisi school help create the biogas digester. Photograph: Elizabeth Ross

Elizabeth Ross, founder of conservation and education charity the Kasiisi Project, which runs the school, explains that most people in the region burn wood to generate power. But this is expensive and environmentally harmful; by using children’s poo they not only get free gas, but protect the forests too.



The project has proved to be a useful tool for teaching students about alternatives to traditional fuel resources. Ross says: “We hope that when they are adults and their turn comes to make choices about what fuel they use or what kind of stove they use, they will be more open to trying new things.”



The alternative fuel is having a surprising impact on children in other ways too. Ross says it is common for children in Uganda to spend hours every day gathering wood for their homes.



“They are really keen to think about ways they can reduce the time they are out collecting wood because they want to do their homework and play with their friends,” she says.

The practice of converting toilet waste into green fuel is not unusual. Last year Kenyan teenager Leroy Mwasaru led a similar project at his school, while students in a rural school in Thailand have used elephant dung to create biogas. Water companies in the UK are also providing gas for heating and cooking to the National Grid using sewage. So with more and more schools embracing renewable energy sources, could poo power be next?



Virginia Gardiner, chief executive of Loowatt, developers of a hygienic waterless toilet that converts waste into biogas, claims the idea has potential in schools, but to provide the amount of gas needed for a large school, toilet and food waste would have to be combined.



“Sometimes it is advantageous to add carbon rich material so that you get more bang for your buck in the digester,” she explains. “But if you take it as an assumption – as I think you can in a school – that you are going to have food waste as well, then you are going to be laughing your way to the bank in terms of the energy you will produce.”



The technology, Gardiner says, is already there to have whole schools running on this system. A company called Qube Technologies, for example, supplies small anaerobic digestion generators to clients such as the military, non-governmental organisations and landowners. She believes innovations such as this could one day be used on a larger scale to provide schools with enough electricity for lighting and cooking.



The educational value of this technology is also high, claims Gardiner. She hopes that by discussing the topic in class, young people will be inspired to develop the next generation of energy producing toilets.



Luke Wynne oversees school programmes for environment charity Global Action Plan and believes there are plenty of ways teachers can bring the subject into lessons. One way to demonstrate anaerobic digestion, the process that releases methane, is to start a worm farm. All you need is a plastic bin or bucket with some holes drilled into it and plenty of organic waste to feed your colony of wrigglers. After a few weeks of feeding, the worms will have produced a rich compost which can be used in the school garden.



For urban schools, a trip to the zoo could also be an opportunity to learn about alternative uses for poo. Zoos dispose of tons of animal waste every day and Wynne claims they often get it composted and sell it for fertiliser. He suggests: “For a school going on a trip to the zoo, as well as seeing the tigers and lions, perhaps they can look at the processes that happen behind the scenes.”



Another option, Wynne suggests, is to connect with a school in Africa that is currently running a project converting toilet waste into energy. A valuable way to empower students to take the lead in improving the environment in their own communities is to allow them to see how it is done in another school and country that is very different to their own.



Students could talk to other pupils facing environmental and societal challenges and look at how they might adapt or build on the innovation that is being developed in another country for their own context. That could take the form of a project to design their own device or system for turning toilet waste into fuel for the school. The lesson should be student led, Wynne insists, to ensure the lesson sinks in.



“From a strictly education and teaching point of view, the ideas the students come up with don’t actually have to be implemented in reality,” he explains. “But you can take the students through the whole process of research and development, product design, and project management, for example.”



He adds that you can bring whole areas of the curriculum into the process, particularly science and maths.



“Who knows what they will come out with in the end?” Wynne continues. “It could be something commercially viable and of interest, but the important thing is that the students understand the process, they develop a product concept and they can even pitch that to their peers or teachers in school.”



While schools in the developing world may be taking poo power seriously, their western counterparts are only just waking up to its potential as a renewable source of energy. The technology is already there and could not only help schools cut costs but is rich in educational value. Where there’s muck there’s brass – it is time we stopped using toilets as waste disposal and started investing in their potential.



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