Análise técnico-econômica sobre eficiência energética e a viabilidade de implantação de sistema de geração fotovoltaica em uma unidade consumidora de baixa tensão

Abstract

The concept of energy efficiency in Brazil is not new and has been discussed and applied for a long time. However, in recent years, this topic has gained significant prominence. Electricity is essential in all aspects of life and becomes increasingly present as society develops. The efficient use of electricity is crucial for economic growth and international competitiveness, ensuring the sustainable development of the electrical sector. The objective of this study is to evaluate how energy efficiency impacts the implementation of a grid-connected photovoltaic system (On-Grid) under the remote self-consumption compensation modality to reduce electricity consumption in a low-voltage commercial consumer unit located in the city of Itajubá. All analyses are based on the annual average energy consumption using electricity bills provided by CEMIG. Additionally, an assessment of the area and location for the installation of the solar micro-plant and its economic feasibility is conducted. The simulations are carried out using the PvSyst software for photovoltaic system sizing. The study demonstrated that the combination of energy efficiency and photovoltaic energy generation is a viable and advantageous solution, both economically and environmentally. The implementation of energy efficiency measures resulted in an approximately 15% reduction in the commercial electricity bill. Furthermore, this optimization allowed for a reduction in the area required for the photovoltaic system and the number of solar panels, making the project even more efficient. Initially, the installation of a 9.78 kWp system with 29 modules and a 15 kW inverter was planned, capable of generating 17,643.64 kWh over 20 years, with an initial cost of R$ 45,450.04 and a payback period of three years. After adjustments in the establishment’s energy consumption and the adoption of energy efficiency measures, it was possible to design a smaller system of 8.14 kWp with 24 modules and a 10 kW inverter, capable of generating 14,718.29 kWh over 20 years, with a reduced initial cost of R$ 35,008.52 and a return on investment in two years.