Your food peels could power your wristwatch

By:  Afia Agyapomaa Ofosu

In the quiet evenings in Ablekuma-Fanmilk, a suburb in Ghana’s Greater Accra region, thirteen-year-old Abdul Latif and his younger brother, Ali, walk from house to house carrying a small sack. They're not begging. They're collecting cassava peels, plantain skins, and yam remains to feed the goats and sheep at home. On rainy days, they spread the peels in the sun to dry first.

This simple act is familiar across many Ghanaian homes. Families feed cooked leftovers to animals and turn peels into compost. Yet Africa still wastes around 195 million tonnes of food every year. Much of this waste ends up in landfills, where it rots and releases harmful methane gas, contributing to climate change.

A 2024 study in Waste Management & Research by Daniel Mmereki and colleagues shows that while composting and biogas from food waste hold great promise, many African countries are not yet making full use of them. Policies, awareness, and investment remain limited.

Far from the streets of Accra, something exciting is happening at Imperial College London’s South Kensington Campus. In the sustainable energy solutions laboratory of the Department of Chemical Engineering, two scientists are looking at the same food waste in a completely new way.

Turning Peels into Battery Power

Dr. Kamogelo Modisane on food waste batteries

Dr Kamogelo Modisane, a chemist from South Africa, works with trays of dried organic material. To her, these are not mere kitchen leftovers.

“We use things you can find in your own home,” she says. “Anything with starch, lignin and cellulose (things people throw away every day) can become a source for our battery materials.”

She and her colleague dry, grind, and heat the peels.

“We are basically cooking the material,” she says with a gentle laugh.

This process creates a special hard carbon for battery anodes.

“This anode is used in pouch cells. So, when you think about the battery in your power bank or some watches, it’s likely this type.”

Instead of relying on expensive imported materials, the team uses sodium and locally available African minerals such as iron and vanadium (a metal used in some batteries).

“We're trying to move away from critical materials like lithium, cobalt, and graphite,” Dr Modisane explains. “With biomass and locally available minerals, we can make batteries without worrying about shortages.”

Two Scientists, One Shared Purpose

Dr Priya Shanmuga explains battery innovation

Working alongside her, Dr Priya Shanmuga focuses on aluminium-based batteries. Using advanced coating techniques, she strengthens the surface of aluminium to make the batteries last longer.

“Aluminium is cheaper and widely available,” she says. “By modifying the surface, we improve how long the battery can last.”

Together, these scientists are building cleaner, smarter energy solutions from materials that are already part of everyday life in Africa.

Speeding Up Discovery

Science journalists from West Africa, including Ghana and Nigeria, who visited the lab saw this innovation come alive at DIGIBAT (the UK’s first self-driving laboratory for energy research). Here, artificial intelligence and robots work together to test new materials rapidly. What once took years can now be done in months.

The young boys in Ablekuma and the scientists in London are connected by the same thing: food waste. They use it to feed animals. The others transform it into energy storage. What was once thrown away may soon power small devices and, one day, support larger clean energy systems across Africa.

The next time you see yam peels or plantain skins, remember this journey. From a home in Accra to a world-class lab in London, humble scraps are becoming part of something much bigger. With creativity and care, yesterday’s waste can help build a brighter, more self-reliant tomorrow.

This report is part of the UK-Ghana ST&I Media Training Programme.

The writer is a science journalist.

E-mail: prissyof@yahoo.com