1. Department of Materials and Energy Science and Engineering, Nelson Mandela African Institution of Science and Technology, P.O. Box 447, Arusha, Tanzania
2. Water Infrastructure and Sustainable Energy Futures, Nelson Mandela African Institution of Science and Technology, Nelson Mandela Rd, P.O. Box 9124, Arusha, Tanzania
3. Electrical Engineering Department, Saint Augustine University of Tanzania, P.O. Box 307, Mwanza, Tanzania