Abstract:
As the global energy demand is increasing rapidly all over the world, hybrid systems of renewable energy sources provide reliable, clean and cost-effective electrical energy. The hybrid system formed by solar PV and hydro power plant is the best choice in Rwanda the country with high potential of hydro resources and solar irradiance.
In this research the hydro logical data with the corresponding power produced in different three consecutive years 2020,2021,2022 were collected at Rugezi hydropower plant which really helped to identify the existed highest power shortage, this highest power shortage was 1850kW and occurred in August 2020 and this is the basis of the designed solar PV power plant. The minimum power produced at Rugezi hydro power plant corresponding to that highest power shortage was 822kW. The designed solar PV power plant to mitigate the power shortage was combined with Rugezi hydro power plant so that the power generated by that formed hybrid system is always equivalent to the installed capacity of Rugezi hydro power plant. During this design the Musebeya site nearest water intake of Rugezi hydro power plant was selected as the best site for solar PV power plant installation ,the yearly average solar irradiance of the selected site is 4.71kWh/day .The installed capacity of the designed solar PV is 2000kWp and the output of the inverter is 1900kWac which is capable to mitigate the power shortage of 1850kWac.The PVsyst 7.3 software and PVsol software were used to design solar PV power plant and Homer pro was used to combine solar PV and hydro power plant so that they form hybrid system ,ETAP software was used for drawing the single line diagram of the hybrid system whereas Matlab software was used for linear programming of the hybrid system. Based on the hybrid system optimization it was found that one generating unit of Rugezi run of the river hydro power plant must be in operation and works in parallel with solar power plant during dry seasons for 1850kWac power shortage mitigation. As recommendation, Rwanda Mountain Tea Ltd the owner of Rugezi hydro power plant should implement this project because this will maximize their profit as independent power producers and mitigate the power shortage which occurs at Rugezi hydro power plant, this hybrid system will increase the country installed capacity and will contribute to carbon emission reduction once it is implemented
