Optimizing Hybird Wind-Solar Plants in Brazil: Addressing Curtailment and Constrained-Off Challenges

Hybrid wind-solar plants in Brazil offer significant advantages due to resource complementarity and shared infrastructure. However, their operation faces two key power generation restrictions. The first is curtailment, an internal power reduction to respect contracted transmission limits when combined output is high, typically affecting the solar plant. The second, constrained-off, is a less predictable reduction imposed by the National Electric System Operator (ONS) due to systemic grid constraints, severely impacting the project's economic viability and revenue predictability. This article presents a methodology to analyze the combined impact of curtailment and constrained-off on the optimal sizing of a solar plant in a hybrid complex. Through a case study of a new photovoltaic plant being added to an existing wind farm, we calculate and compare the resulting generation losses across different installed capacity scenarios to support decision-making.