Physics student invents power backup system

The University of Malawi never runs out of reasons to celebrate its students, due to their high academic excellence, their determination, and their innovations. One of the departments that can always be relied upon to innovate is the Department of Physics. A student in the department, Enoch Kachokola, a 4th Year Bachelor of Science in Electronics students, is one of the recent innovators, having recently invented what he calls a power backup system.

The invention is not part of Kachokola’s school work, but has arisen from his realization that he can use knowledge gained at the university to solve some problems in the country. He points out that the invention arose from two specific challenges. The first was the load-shedding programme implemented by ESCOM in Malawi. “I observed the adverse effects that the programme caused, mainly in terms of inconveniences that many people experienced during power outages. I decided to come up with a power system that can eliminate this problem,” he said. Secondly, he points out that his interested in assisting health centres in rural areas, whose work is usually negatively affected by the absence of power backup systems. He hopes that he can eventually create various machines that may be donated to these health centres.

It took me 9 months to develop the current machine,” Kachokola said. “There are a number of factors that caused this, such as the institution closure, and the fact that I had to source some of the components, such as the battery management system, from China. There is a sponsor who helped me to acquire these parts. The machine has a total of 352 cells. This translates into a capacity of around 200 amp-hours. If we do the mathematics, it comes up to around 3.3 Kilowatts. This power is converted to AC, which can power a load of a maximum of 4 Kilowatts. I have tested this with various items, such as hotplates, kettles, irons, units and other equipment. With smaller loads such as entertainment units, lights and laptops, it can go for up to 24 hours or more. For this prototype, I managed to secure old laptop batteries that had not completely lost their capacity.”

Kachokola insists that his machine is not merely an inverter, but rather a portable backup system complete with an inverter, batteries, overload and overheating protection. The equipment relies on utility power (ESCOM) and takes between 3 to 5 hours to fully charge. He installed a changeover switch that enables the machine to change from utility power to battery power. The battery management system (BMS) ensures that the batteries will not overcharge.

Apart from designing and installing the scientific components, Kachokola also designed its outward appearance using graphic design software. Currently, the Physics Department is assisting Kachokola and other students with patenting some projects that are under development. However, he points out that if people are interested, they may contact him so that he can design a power backup unit that will meet their specific needs, complete with component costs and labour charges