Impactos técnicos e de operação da geração distribuída fotovoltaica na rede de transmissão

Abstract

The study addresses the technical and operational impacts of photovoltaic distributed generation (DG) on the transmission network of the National Interconnected System (SIN), analyzing the challenges imposed on the quality, reliability, and stability of electricity supply within the context of Brazil’s energy transition. The purpose of the study is to understand how the accelerated expansion of DG, originally connected to distribution networks, has altered the behavior of net load and influenced system operation, including at transmission levels. The methodology was based on bibliographic and documentary research, grounded in official reports from the Brazilian Electricity Regulatory Agency (ANEEL), the National Electric System Operator (ONS), and the Energy Research Company (EPE), in addition to technical studies such as the *Diagnosis and Perspective on the Evolution of Generation Curtailments in Brazil* and the *Ten-Year Energy Expansion Plan (PDE 2035)*. Real cases of disturbances in the SIN were analyzed, including the August 15, 2023 event, the near blackout on Father’s Day 2025, and the blackout of the Iberian Peninsula, in order to identify parallels among the operational difficulties associated with the massive integration of renewables. The analysis of real cases shows that, although DG contributes to the diversification of the energy mix and the reduction of losses, its high penetration without proper planning can cause reverse power flow, local overloads, voltage control difficulties, and reduced system inertia, increasing the risk of instabilities. It is concluded that the safe integration of DG requires the improvement of grid procedures, investment in storage technologies, and the expansion of transmission infrastructure. The study also highlights the importance of adopting flexibility measures and coordinated regulation so that DG can be consolidated as a strategic asset for the reliability and sustainability of the Brazilian electric sector.