Two fourth year students from the College of Mechanical Engineering at Makerere University have invented a mechanical powered battery charging system that generates electricity from walking. For many years, electricity in Uganda has been generated from water, sun and wind.
This however is likely to change with the invention of electricity from walking by Ivan Ojandu Ezati and Ogwang Joshua. With the emerging trends, there has also been a change in the energy harvesting process. According to the book Emerging Research Trends in Electrical Engineering, human movement could be a potential source of energy harvesting. It is from these emerging trends that the two students got inspiration to try out something that is both environmentally friendly, cheap and readily available to even the people in remote areas.
According to Ojandu, the project is in its mid-stages and its main aim is to provide an alternative energy source that can be afforded by every person in Uganda, since the project is more of a humanitarian cause in that it targets people involved in a lot of walking. "We thought of something that is different from the other energy sources and does not require a lot of resources to use. Walking is a day to day activity that can be done almost by everyone," Ojandu said.
The project will involve use of piezo electric discs that will convert physical energy to electrical energy and use of diodes to amplify current. This will involve connecting the discs to amplify the voltage and the terminal ends connected to the diode that changes alternating current to direct current, which is then connected to the Elithium-Polyma battery (Li-Po) to store the charge.
"The piezo discs can be installed in a shoe carpet on the heel or the toes, such that as someone walks, he or she applies pressure that generates physical energy,” Ogwang said. According to Anuray Kasyap in the book Miniature Portable Ambient Energy; Harvesting Modules powered by RLP Technologies, miniatures are portable energy harvesting modules that get energy from the surrounding and convert it to usable electrical power that can be stored in batteries for further use.
However according to Ojandu, for the meantime, the project is only suitable for small devices since the current generated is little. And for one to generate enough current to charge a heavier device, he or she will have to connect a number of discs in series to a battery. “My project is still being tried on a small scale but with time, after it has been tried and approved, we will work on a larger project that will be able to charge bigger devices,” he said.
The biggest challenge that the students continue to face is limited resources and funding. Some of the required equipment are scarce and this has halted their work. “It is not easy getting some of the components required for the project for example the piezo electric discs are not readily available in Uganda,” Ojandu added.
The student is partnering with his supervisors, Dr. Betty Nabuuma and Dr. Francis Mujuuni to jointly finance and accomplish the project. The supervisors come in to provide the necessary equipment needed and also provide guidance where necessary.
According to their university supervisor, Dr. Betty Nabuuma, the project has potential of charging smaller units and with time they will be able to upgrade to larger ones. “The recent results from the project showed that the product has potential to charge lithium batteries, though there is room for improvement since it showed positive signs for further development,” Nabuuma said.
For every student in the Department of Mechanical Engineering to graduate, they are required to do such projects. The projects are categorized into three groups namely; design and construction, design and simulation and lastly research. The projects run for a year whereby the students do project proposals in the first semester and the last semester is dedicated to fabrication, design and construction of what they are planning.