Storage at the edge: Distributed BESS as a technical and regulatory solution for Brazil's energy transition

As distributed solar generation expands rapidly in Brazil, new operational challenges have emerged, including renewable curtailment and steep evening ramps in net load. Battery Energy Storage Systems (BESS) are widely seen as a promising solution, but their effective deployment, particularly at the grid edge, depends on technical feasibility, economic viability, and regulatory alignment. This study offers an integrated, scenario-based evaluation of three BESS deployment strategies in the Brazilian National Interconnected System (SIN): (i) operating standalone BESS as independent market agents, (ii) shifting low-voltage consumption via behind-the-meter storage, and (iii) shifting distributed photovoltaic (PV) injection through co-located BESS. Drawing on real operational data from the 12-month period between July 2024 and June 2025, the analysis assesses each strategy across technical, economic, and regulatory dimensions. The study makes three key contributions: it introduces an empirical benchmark for assessing distributed storage performance in high Distributed Generation (DG) contexts using real-world data, it reveals the structural misalignments between economic incentives and system needs, particularly regarding tariff design and spot price signals, and it identifies actionable regulatory gaps that must be addressed to unlock the full potential of distributed flexibility. These findings provide practical insights for system planners, regulators, and policymakers seeking to align distributed energy resources with grid reliability and decarbonization goals.