Case Studies with BESS: Association for Mitigating Constrained-off and LRCAP

The integration of battery energy storage systems (BESS) in renewable power plants has become a highly relevant topic in the electricity sector. With the expansion of solar and wind generation, the efficient management of generated energy is essential to ensure the stability and profitability of projects. In this context, Aeroespacial conducted studies to evaluate the feasibility of using BESS in different scenarios, considering both the mitigation of energy and financial losses due to constrained-off and as a product for the Capacity Reserve Auction with Storage.

Case Studies: BESS Sizing

1. BESS in Photovoltaic Power Plants with Constrained-off

The first analysis focused on integrating BESS into a photovoltaic plant (UFV) subject to generation curtailments (constrained-off), a common situation in scenarios of transmission grid congestion. To quantify and mitigate these impacts, the following aspects were considered:

• Future generation projections and constrained-off losses from a systemic perspective (considering generation forecasts from all sources, demand, distributed generation, transmission, ONS reliability criteria, among others);
• Modeling of the joint operation between the plant and BESS, analyzing storage charging and discharging;
• Economic evaluation considering CAPEX, OPEX, transmission system usage tariff (TUST), and return on investment.

The results demonstrated that integrating BESS reduced curtailment losses and improved the plant's operational efficiency, increasing revenue predictability and enhancing operational security.

2. BESS for Capacity Reserve Auction (LRCAP)

The second study focused on the use of BESS in an independent context, aimed at supporting the electricity system's capacity reserve with a view towards the LRCAP with storage in 2025. The key aspects considered were:

• Connection point flow and technical limitations;
• Equipment characteristics in relation to local climate conditions;
• TUST/D of the project;
• Definition of optimal sizing and augmentation strategy for system expansion over time.

The results indicated that BESS is a viable solution for capacity reserve, contributing to grid stability and enabling better energy dispatch management in critical moments.

Final Considerations

The studies conducted by Aeroespacial reinforce the importance of energy storage as a strategic solution for market participants and the electricity sector as a whole. The integration of BESS in renewable plants helps mitigate curtailment losses, optimize the use of electrical infrastructure, and strengthen system reliability. Today, Aeroespacial has been conducting studies considering different perspectives on ancillary services that can be provided by standalone BESS solutions or those associated with plants. Furthermore, its application in LRCAP demonstrates economic feasibility and contributes to grid resilience. With this, storage systems are becoming an essential element for the future of the Brazilian electricity matrix.

To discuss:

(1) Future constrained-off quantification,

(2) BESS for constrained-off mitigation,

(3) Grid margin for plants and/or BESS,

(4) LRCAP storage 2025,

(5) Ancillary services and revenue stacking with BESS,

(6) Auctions for isolated systems,

and other related topics, schedule a meeting with our specialists to discuss how we can contribute to your project. Contact: [email protected] | +55 51 99951-2174