Design Of A Net Metered Solar System In Makerere University

Abstract

Uganda is a growing economy and energy particularly electricity is one of the major drivers of this growth. There is however an overdependence on only one source of electricity which is hydropower in Uganda. As a result, the cost of electricity is high and there is a lot of power rationing which affects the reliability of this source of electricity. This project aims to tap the solar energy at Makerere and utilize it to produce electrical energy. The produced energy will be consumed by the University and the extra energy will be sold to the grid through Net Metering. The generation of this solar energy will reduce the electricity expenditure incurred by the university by at least 20%. The project was carried out by first estimating the solar PV potential of Makerere University as well as the space the panels would occupy. This involves the use of software called PVGis. Then this was followed by data collection. This was done through interviews and site visits. One of the sites we visited was Tororo North Solar plant. Then, we did the analysis of the effect of the PV power plant on the already existing system. This was done using Dig Silent software. Lastly, we did the financial appraisal. This was carried out using a mathematical model to get the cost of equipment and cost benefit analysis. From the work done we found that although the name plate of the plant is 1204kW, we shall produce 135,500 kWh per month which is about 21% of the energy consumption in Makerere per month. We also discovered that for optimum operation the modules should be place at a 10° tilt angle and facing the south direction. We applied the use of packing factor (51%) to determine the actual space the panels will occupy and leave spacing for maintenance of the panels. The simulations carried out revealed that the network losses and voltages do not vary significantly after the addition of our solar energy to the Makerere Network. The payback period for our project will be about 7years and after the seven years the project will continue to reduce the expenditure by 21% every month. The 135,500 kWh produced monthly will save the university about 63Million Uganda shillings.