Daniel Mesquita

The discussion about energy security and the expansion of electrical capacity in Brazil took on new dimensions with the LRCAP 2/2026 (Capacity Reserve Auction in the form of power), held on March 18th, in which power volumes were negotiated, mainly from hydroelectric and thermoelectric plants, with the expectation of guaranteeing the continuity of electricity supply to the SIN (National Interconnected System), meeting the need for power and energy at any time, with reliability and security, even during critical periods. In this scenario, Battery Energy Storage Systems (BESS) are emerging as an increasingly competitive alternative to traditional thermal power plants, especially in applications that require operational flexibility, rapid response, and integration of renewable energy sources. Historically, thermal power plants have been the main solution for ensuring additional power to the interconnected electrical system during peak demand periods or operational contingencies. However, technological advancements in battery storage systems are altering this paradigm, offering significant gains in efficiency, sustainability, and speed of deployment, while simultaneously reducing dependence on carbon-intensive assets. Quick response and operational reliability. One of the main advantages of BESS is its speed of response. Energy storage systems can come online in milliseconds, supplying power to the electrical grid almost instantaneously. One example is Henan, China, a province with high population density and a strong industrial presence, characterized by high load variability, where a 33,5 MWh storage system from LONGi Energy Storage acts as an integrated solution between generation, grid, and load, responding in milliseconds to smooth load fluctuations. Thermal power plants, depending on the technology used, can take several minutes, or even hours, to reach full operational load, especially in combined cycle plants. In the context of LRCAP, this characteristic is especially relevant, as the system operator seeks resources capable of responding quickly to frequency fluctuations, network failures, and instantaneous demand peaks. In this respect, BESS offers greater predictability and operational reliability, especially in short-duration, highly critical events. Sustainability and decarbonization Another important point is the environmental issue. BESS systems have no local CO₂ emissions during discharge operation, while thermal power plants fueled by natural gas, diesel, or coal continue to contribute significantly to emissions from the electricity sector. Additionally, when charged with renewable energy, batteries allow for the capture of surplus solar and wind power generation that would otherwise be lost, increasing system efficiency and reducing energy waste. As investors, consumers, and regulators increase pressure for ESG and decarbonization targets, storage solutions are gaining strategic relevance. Furthermore, the expansion of intermittent sources, such as solar and wind, requires technologies capable of balancing the variability of generation without increasing emissions, thus avoiding the lock-in of fossil fuel assets in the long term. In other words, the need to maintain carbon-intensive infrastructures in operation for decades due to investments already made. An example of this is the 30 MW photovoltaic plant combined with 50,16 MWh of storage from LONGi Energy Storage in Montalto di Castro, Italy, a region with a strong presence of solar generation and high exposure to seasonal irradiance variations, which requires greater capacity to manage intermittency. The project is expected to export more than 332,4 GWh over 18 years, preventing the emission of more than 74.000 tons of CO₂ annually and meeting the equivalent consumption of approximately 123.000 Italian homes. Photo: LONGi/Disclosure In this context, battery storage is consolidating itself as a fundamental element of the energy transition, aligning with Brazilian guidelines for the sustainable expansion of the electricity sector, the increasing inclusion of renewable sources in the energy matrix, and the objectives of reducing emissions and increasing the operational flexibility of the system. Superior operational efficiency. BESS systems also feature high energy efficiency. LONGi Energy Storage's Utility solution, for example, boasts an average operational availability of 99% and an RTE (Round Trip Efficiency) of approximately 93%, an indicator that represents the ratio between output energy and input energy throughout a complete load and discharge cycle. Photo: LONGi/Press Release. In comparison, thermal power plants have significantly lower efficiency in the energy conversion process, generally between 35% and 60%, considering thermal losses and fuel consumption. Furthermore, BESS reduces energy waste and allows for greater utilization of renewable energy generation, especially during periods of low demand and high production. Speed of deployment and modularity. Another important differentiator is the implementation timeframe. BESS projects can be implemented in approximately 12 to 24 months, depending on the project scale and licensing processes, while thermoelectric projects often require between 3 and 6 years, considering environmental licensing, civil works, fuel infrastructure, and electrical connection. This speed allows the electrical system to be more responsive to increased demand and emergency capacity needs, as well as enabling gradual expansions through the high modularity of the systems, keeping pace with load evolution or operational needs, as is the case with ancillary services. Locational flexibility and congestion reduction: Storage systems can be installed close to load centers, in substations, or in regions with transmission restrictions. One example is the project in Edinburgh, Texas (an American state characterized by strong growth in renewable energy generation, especially wind and solar, and by frequent power grid stress events) with the implementation of 25MWh of the LONGi Energy Storage solution, aimed at increasing the stability and reliability of the power grid, providing ancillary services such as frequency regulation and voltage support. This flexibility reduces the need for large electrical infrastructure projects and helps alleviate congestion on the grid. Photo: LONGi/Disclosure Thermal power plants, on the other hand, typically depend on a continuous supply of fuel, water availability for cooling systems, and more complex environmental processes, which limits their project location flexibility. In the Brazilian context, this characteristic is particularly relevant in regions with rapidly growing demand or high penetration of renewable energy generation. Lower operating costs: Although the initial investment for a BESS project is still relatively high, operating costs tend to be significantly lower when compared to thermal power plants. Storage systems do not rely on fossil fuels and have lower mechanical complexity, which reduces operating and maintenance costs over time. Thermal power plants, on the other hand, remain exposed to the volatility of natural gas and diesel prices, as well as supply logistics, factors that can significantly impact operating costs. Multifunctionality of BESS systems Another relevant aspect is the ability to provide multiple services simultaneously to the electrical system. In addition to power delivery, BESS systems can perform the following functions: Frequency control; Voltage regulation and stabilization; Black start (ability to re-energize the system after blackouts); Energy arbitrage to optimize economic benefits; Support for the integration of solar and wind power plants; Grid stabilization. This multifunctionality increases the economic value of the asset and expands its revenue potential, especially in evolving markets like Brazil. The role of BESS in the future of the electricity sector In the current context of the Brazilian electricity sector, there is enormous potential for BESS in replacing peak thermal power plants, meeting rapid load ramp-ups, supporting renewable energy expansion, and postponing investments in transmission. With the continued reduction in battery costs and the maturation of capacity markets, the trend is for energy storage to assume an increasingly important role in the Brazilian electricity matrix, which has long lacked solutions that could be provided by the use of this technology. What's lacking is proper planning that explores the full potential of services that batteries can provide to the system. The future of the electricity sector is likely to be marked by the complementarity between technologies: batteries providing flexibility and rapid response, while thermal power plants – fueled by increasingly smaller carbon footprints – remain relevant for prolonged supply and structural energy security.

Daniel Mesquita

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BESS in the Brazilian LRCAP: advantages compared to thermal power plants in expanding the capacity of the electrical system.

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