Esource is a bicycle powered electrical cable recycling system to be used in developing countries. It allows the copper to be recovered from the cables without being burnt, which is currently the most common practice. It also preserves the plastic insulator meaning that this too can be sold providing additional income to workers. It consists of two machines: a shredder which shreds the cables leaving a mixture of plastic and copper particles, and a separator that uses gold panning techniques to separate the copper from the plastic, leaving clean copper, and clean plastic. It is designed to be manufactured in developing countries as cheaply as possible. It can process around 5kg of wire per hour and this could be further increased with more development.
I found that 70% of the west's electrical and electronic waste is illegally exported to developing countries where it has a huge impact on the environment. The worst practice is the burning of electrical cables to recover the precious copper they contain, leading to serious health problems. In Accra, Ghana, the dioxin emissions from this burning is equivalent to up to 15% of Europe’s dioxin emissions.
It was the fact that I could see the real impact of my waste that motivate me. In Ghana I was amazed by the resourcefulness of the people and their enthusiasm despite the difficult circumstances they live in. I knew that I wanted to do something to impact this situation. It turned out that far from being a last resort people were making above average wage through this work, and burning wire was providing youngsters with a high enough income to attend school. If ewaste could be dealt with sustainably in developing countries it could be a great source of income to these communities.
The project was developed mostly through prototyping and thinking rather than using CAD and sketching, although these were both used to refine the final designs.
I started by developing hand tools but quickly realised that these would be too slow to be economically viable. I then started looking at small scale shredders from plastic extruders and decided these were a suitable scale.
The separator required much more development. I started by trying to replicate the techniques used by industrial cable recycling machines in Europe, which mostly use air jets and vibration. This proved very hard to fine tune and expensive to produce. The final piece of the puzzle came from a book about gold panning that led to the development of the final separator which achieves a separation of over 97%.
My trip to Ghana had a huge impact on the development of the project as it provided me with insights into the lives of the people working their that I could never have gained through literature.