The company aims to incorporate photovoltaic (PV) systems into its extensive real estate portfolio to boost sustainability and reduce energy costs. However, accurately estimating roof areas and assessing the potential energy yield from solar installations across diverse properties poses a significant challenge. Current methods lack automation and scalability for large portfolios. The focus is on properties located in Switzerland.

The project involved conducting a thorough literature review and an expert interview to explore existing roof estimation models and their applicability. Various tools were evaluated, including several Solar APIs and PVGIS. An Excel tool was developed that automates the calculation of PV potential, integrating data from APIs, and performing financial viability assessments based on roof area, solar radiation, and energy tariffs. Testing and validation were conducted using historical data and expert input to ensure accuracy and reliability.

The thesis resulted in an Excel-based tool developed to estimate the photovoltaic (PV) potential of the companies real estate portfolio. The tool automates roof area estimation and calculates solar energy potential based on location, roof size, and solar radiation. It provides estimated returns for each property by factoring in energy output, installation costs, and rates, helping evaluate the financial viability of potential PV installations. Testing showed that well-positioned roofs with optimal sunlight yielded higher returns, while some roofs, particularly gabled ones, showed marginal or negative returns due to incomplete area capture. Despite some limitations in roof area estimation, the tool offers valuable financial insights and supports decision-making on solar energy investments. Future improvements in roof area accuracy and regional expansions will enhance the tool's scalability and the companies sustainability goals. In Germany, state-specific solar cadastres offer limited coverage, making the tested Google Solar API a promising alternative for broader analysis.