Despite sharp decline, Brazil's hydro reservoirs in a 'comfortable' situation

Water levels in Brazil’s hydroelectric reservoirs fell significantly in the last year but the national energy storage situation remains comfortable, a local expert told BNamericas. 

According to data from electric power system operator ONS, the southeast/center-west subsystem is currently at 66.3% of energy storage capacity, almost 20 points down from a year ago. 

In the northeast and south, the levels fell from 79.3% to 68.1% and from 93.7% to 85.0% of capacity, respectively. 

In the north – a region that experienced a serious drought last year – the figure was flat at approximately 90%. 

The southeast/center-west subsystem is the most important in the country, accounting for 70% of the country’s hydroelectric storage capacity. 

Given the scenario, electric power watchdog Aneel changed the electricity rate flag after two years to a higher rate, and could activate the red flag in the coming months.  

Alexandre Nascimento, managing partner and meteorologist at consultancy Nottus, said last year was the best on record in terms of reservoir levels. 

"Even with the drop in reservoirs in recent months, they can still be considered full at the moment, compared to the historical total. This situation is still more comfortable than the average of recent years," he told BNamericas. 

For the coming months, according to the expert, the expectation is for normal to slightly below average rainfall in most of the national electricity system and normal to slightly above average in the south. 

"In general, this would imply an estimate of average depletion of around 20pp of the electricity system by the end of the dry period, at the end of October, reaching close to 48-52% [of capacity]. Last year, at the end of October, we had 68%," Nascimento said. 

SUPPLY ASSURANCE

During a meeting of the electricity sector monitoring committee (CMSE) last week, mines and energy minister Alexandre Silveira stressed the importance of planning in the sector to find measures to increase the supply of resources to meet the country's need for power generation. 

He highlighted the decision to reduce the flow of the Jupiá and Porto Primavera hydroelectric plants on the Paraná river to conserve reservoirs during the dry season and avoid resorting to thermal power plants. 

"We're also making progress with investments in various projects across the country and in modernizing the electric power grid, always seeking a balance between low tariffs and energy security," said Silveira.