Feasibility study of Hybrid PV-Hydropower complementarity: Case study Mukungwa HPP

Abstract

Photovoltaic-Hydro hybrid generation is a new multi-energy hybrid system combined with respective advantages, solar energy and hydropower. Stability and reliability are crucial parameters in power system operation. This research topic focuses on studying hybrid PV– Hydropower complementarity; the case of Mukungwa Hydropower Plant (HPP). This is a power station located in Rwanda’s Northern Province. It was built in 1982 and has an installed capacity of 12 MW. Since its construction time, it has been operated as a reliable power plant. This is the plant that stabilizes the voltage for the Northern network. However, the power produced by the plant is reduced due to the high evaporation of water from the dam and hence, reduces the power generation during the summer season. This power reduction is estimated to be around 3 MW that is going to be covered by using the installation of a photovoltaic (PV) plant. It has been proposed in this study that a PV system can complement that power deficit during the high sunshine time. To validate the recommendation and check whether the system will be capable to supply the required power, the system is modeled and simulated using HOMER and PVSYST software. This study shows that the power reliability of Mukungwa HPP is improved by 5%. That is; the reliability is increased from 0.94 for a single generator to 0.99 after adding another generator in parallel. Economic analysis also shows a positive net present value (NPV) to prove the viability of the project.