Unlocking the Potential of Solar-Hydro Hybrid Solutions: Feasibility and Economic Analysis

Abstract: Hybrid solutions that combine multiple renewable energy sources, such as solar power and hydro power, are gaining popularity as a means of meeting the growing energy demands while minimising environmental impacts, but also as an opportunity of connecting solar power plants to the grid in areas where this might not be possible unless large investments are made. This master thesis aims to evaluate the feasibility and economic viability of integrating solar panels with an existing grid connection point at a hydro power plant, along with the introduction of an energy storage solution using a hydro power plant reservoir. The study is conducted in cooperation with Eolus Vind AB and focuses on a selected site at Karsefors in southern Sweden, but also discusses hybrid solutions in a broader context, considering other solar and hydro power technologies such as pumped hydro power and floating PV, emphasising their potential advantages and challenges. Four different scenarios are simulated and analysed, including standalone hydro power production, standalone solar power production, and two hybrid solar-hydro power production scenarios with and without an implemented refinement method. The simulations provide insights into the benefits and disadvantages of implementing a hybrid system compared to standalone solar and hydro power plants. The study examines technical aspects such as grid utilisation, curtailment and refinement methods, as well as economic factors such as income generation, net present value (NPV), internal rate of return (IRR) and payback time. The results indicate that the technical and operational feasibility of a solar-hydro hybrid system at a shared grid connection point was found to be viable. The study highlights the potential to reduce curtailment and grid capacity limitations through refinement methods. However, curtailment may still be necessary during certain periods. The economic analysis revealed mixed results with suboptimal financial metrics but higher income for the hybrid scenarios compared to standalone systems. Alternative hybrid solutions like pumped hydro power and floating PV offer additional possibilities for storage and synergies, but require trade-offs and consideration of implementation costs and environmental impacts.