Technical and economic feasibility study for the expansion of a PV installation with surplus energy storage integration

Abstract

This project analyzes the technical and economic feasibility of expanding an existing industrial self-consumption photovoltaic installation, considering at the same time the possibility of adding energy storage systems with batteries. This analysis is carried out in parallel to a real project undertaken in an internship with a company of this sector. The main objective of the project is to study and clearly understand this type of installations in order to determine the most suitable project for the client based on their specific circumstances. To achieve this, it is also essential to understand this energy source in its context within the energy sector. The methodology used is mainly based on Wattwin, an integrated software for solar selfconsumption projects, which offers multiple analysis options. For this analysis, the client’s actual electricity consumption data is imported and its available surface area is studied in order to create simulations of various installation proposals, with or without the inclusion of surplus energy storage. The economic factor also plays an important role in this analysis, with economic indicators such as NPV (Net Present Value), IRR (Internal Rate of Return) and payback period being taken into account. The results show that the proposed PV system expansion, maximized to the client's high energy demand and available surfaces, offers a technically and economically feasible solution to enhance energy self-sufficiency. With a total installed capacity of 303.88 kWp, the system is expected to produce 410.17 MWh annually, reducing the client's grid dependency by 23%, which could increase to 28% with the integration of battery storage. The PV expansion alone offers an attractive payback period of less than 5 years, with estimated annual savings of 37,020 €, while the addition of batteries increases savings to 44,745 €, albeit with a longer payback period due to the seasonal underuse of the storage system. In conclusion, both technical alternatives, with and without battery storage, have been presented to the client, along with their respective economic and operational implications, to support an informed decision based on their specific needs and priorities. The project successfully meets its objective of providing a well-founded, site-specific proposal for the expansion of the PV installation, along with a realistic assessment of the benefits and limitations of surplus energy storage.