Techno-economic feasibility assessment of integrating floating solar with hydro: a case study for Victoria Power Station Sri Lanka

Abstract

The addition of floating solar photovoltaic (FSPV) to existing hydropower facilities is a potential game-changer in the incorporation of renewable power sources while maximizing resource allocation. This study explores the potential deployment of an FSPV system configuration at the Victoria hydropower station in Sri Lanka from a technical, as well as a financial perspective. It explores the possibility of approximately 93 MWp of solar capacity being placed on the surface of the reservoir, which would result in the generation of 133.5 GWh of energy per year. By utilizing the existing grid structure at Victoria, this method serves as a cheaper solution than ground-mounted and independent floating solar plants. The analyzed comparative levelized cost of electricity (LCOE) data is suggestive of a hybrid model in comparison to the standard solar PV design in the country. Dynamic simulations were carried out on the proposed system with the aid of Power System Simulator for Engineering (PSS/E) and a dynamic model received from the Ceylon Electricity Board (CEB) Transmission Division. The outcome suggests that the complementary operation of FSPV and hydropower does not put system stability at risks, since the frequency response and bus voltage profiles of the system are within allowed limits under all system disturbances. Furthermore, the existing arrangement for power sharing between solar and hydro resources offers additional energy security in that it permits dominance of solar over daylight hours while allowing hydro resources to be stored for generation during the night. The results of this study elaborate that the complimentary use of floating solar PV (FSPV) and hydropower has the potential in making the country’s energy transition economically sustainable. Even though there may be some boundaries, the analysis does set up a strong case for the future large-scale implementation of hybrid FSPV- hydro systems.