The current dissertation examines the role of available financial instruments in improving the economic attractiveness of investments in photovoltaic systems, which are combined with energy storage systems for industrial applications. More specifically, this analysis focuses on the financial instruments proposed in the Roadmap for the Energy Efficiency of Buildings, as published in the Government Gazette in July 2025. In this light, their potential application in the PETech investment project of Nera Kritis S.A. was evaluated. The methodology followed was based on quantitative financial analysis, as well as on the comparative evaluation of alternative financial mechanisms. Thus, a representative investment scenario for the installation of a 1 MWp photovoltaic system in combination with a 2 MWh energy storage system was developed. For this scenario, cash flow, Net Present Value (NPV), Internal Rate of Return (IRR) and payback period analyses were performed. At the same time, different financing scenarios were examined, including self-financing, subsidies, bank loans, leasing, ESCO models and Power Purchase Agreements (PPAs). The results showed that the investment can become financially viable even without receiving external financial support. However, subsidies and mixed financing schemes improve efficiency indicators while also reducing investment risk. In conclusion, this study indicates that the combination of public support and limited borrowing is the optimal financing solution for industrial enterprises seeking their energy transition, while maintaining their financial flexibility and competitiveness.