The plant does not have a large reservoir, which affects water availability; the same is true of the Santo Antônio hydroelectric plant, which operates at 10% of its capacity.
Two of Brazil’s largest and newest hydroelectric plants are facing severe operating restrictions due to the severe drought. The Belo Monte plant, the country’s second largest in terms of installed capacity, has been generating less than 3% of its projected electricity due to low water availability. The Santo Antônio plant is operating at 10% of its capacity.
A target of environmentalists before and after its construction, the Belo Monte plant in Pará has the capacity to produce 11,233 MW of energy (or 11.2 GW). But with the drought, it is generating 323 MW on average in September, −2.9% of its capacity. The data is from ONS (National Electric System Operator).
Performance is a reflection of worst drought recorded in Brazil since the beginning of the historical series, in 1950. In 2023, Belo Monte dealt with a severe drought of similar proportions. The rains in the Amazon, which normally begin between November and December, were delayed and only arrived in January of this year.
In 2024, the hydroelectric plant did not generate the total amount of energy for which it was designed on any day. The highest daily production was 10,397 MW, on April 30. Generation levels were above average from February to May, but then fell drastically with the return of the dry season, since Belo Monte does not have a reservoir to store water.
This year, the plant’s lowest daily energy generation was 174 MW on August 27. Currently, only one of Belo Monte’s 18 turbines is in operation due to the low level of the Xingu River. Each turbine has a capacity of 611.11 MW – equivalent to an Angra 1 nuclear power plant (with around 640 MW).
The fact that Belo Monte generates energy well below its capacity is not new during dry periods. Because it is located in a region where there is significant rainfall from December to May, the plant produces less during the dry months. This is mainly due to the fact that the plant does not have a large storage reservoir.
SANTO ANTÔNIO AT LOW LEVEL
In operation since 2012, the Santo Antônio plant has also suffered from the drought. Considered the 4th largest hydroelectric plant in Brazil in terms of power, with 3,568 MW of installed capacity, it has an average generation of 370 MW in September (10.3%).
Like Belo Monte, the hydroelectric plant recovered from the 2023 drought with rains from January to May, but then the lack of rain began to reduce the available water. The highest daily energy generation in 2024 was on April 8, with 3,228 MW. And the lowest, of just 241 MW, was recorded last Wednesday (September 18).
Santo Antônio is located on the Madeira River, which is facing the worst drought in its history in 2024. On September 14, the water level reached a height of 41 centimeters in the section that passes through Porto Velho (RO), according to the SGB (Brazilian Geological Service).
The plant has 50 bulb turbines, which, together with the concept of a run-of-river reservoir, significantly reduces the reservoir area. Of the generating turbines, 44 supply the Southeast and other regions of the country. The other 6 are dedicated exclusively to Rondônia and Acre.
LACK OF RESERVOIR
Both plants, located in the northern region of the country, operate using the “run-of-river” model. In other words, without a large accumulation reservoir. In this model, the force of the river current is used to generate energy, without the need to store water. In addition to Belo Monte and Santo Antônio, this is also the case with the Jirau plant.
Despite being a sustainable model, with environmental and social advantages, the run-of-river plant has impacts on the system. This is because, in periods of prolonged drought, these structures may run out of water to generate electricity, since their small reservoirs do not guarantee operation for long periods.
In recent years, the country has built few hydroelectric plants, and all of them are run-of-river. This policy aimed at reducing environmental impact makes gigantic plants such as Belo Monte, Santo Antônio and Jirau hostage to the natural flow of rivers, reducing the delivery of energy and the security of the country’s supply.
In the case of Belo Monte, the hydroelectric plant has a flooded area of approximately 480 km². According to the original project, it was supposed to be 1,200 km² with the construction of a large reservoir. However, the idea was defeated in the discussions that preceded the implementation. If the model had been implemented, the plant’s capacity would now be 19,000 MW, instead of 11,233 MW.
Construction of Belo Monte began in 2011. It was inaugurated in 2016, in a project that cost around R$20 billion. The last of the 18 turbines was inaugurated in November 2019. As it is a run-of-river hydroelectric plant, it only delivers a volume of energy close to the projected volume in half the year.
According to the Aneel (National Electric Energy Agency), the last plant with a significant reservoir that entered the electrical system was Serra da Mesa, in 1998. After that, the country prioritized run-of-river plants.
Within the government, there is an intention to review this policy to make new hydroelectric plants with reservoirs viable. Despite the will of the Ministry of Mines and Energy, the idea is viewed with reluctance by the Ministry of the Environment.
Read more about drought:
#Due #drought #Belo #Monte #generates #projected #energy