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SAO PAULO, March 22 (Reuters) - Brazil's state-run oil company Petroleo Brasileiro SA threatened to turn off several thermal power plants it operates in the country due to lack of payment, according to a letter sent by the company to Brazil's electricity regulator Aneel.
Petrobras, as the company is known, said in the letter seen by Reuters on Tuesday that overdue payments for thermal generation have reached 1.5 billion reais ($418 million) and are hurting its cash reserves.
The oil company, which is already facing financial hurdles due to falling oil prices and a far-reaching corruption scandal, has 20 large thermal power plants in several Brazilian states with total capacity of 6,000 megawatts.
It should be paid monthly following the settlements at power clearing chamber CCEE, but a legal dispute involving several power companies have put those payments on hold for months, sharply reducing the amounts passed on to thermal generators.
"It is urgent that the Energy Ministry takes action and find a solution to avoid that Petrobras reaches a situation where there will not be other option than to halt the thermal generation", said the letter signed by the company's Power & Gas director Hugo Repsold Junior.
Brazil went to the brink of a power rationing early last year after back-to-back droughts in 2013 and 2014 depleted hydropower dams' generation.
During that period, the country turned on basically the whole network of thermal power plants, provoking a spike in power bills. The overdue bills currently owed to Petrobras stem mainly from hydroelectric and power distributing companies who drew on the thermal plants' output to meet customer demand.
Ample rainfall returned last year together along with the strongest El Nino weather phenomenon in decades and stabilized the hydro power system.
Petrobras asked for the government to use money it raised by charging consumers extra amounts during the crisis to pay the overdue bill and reduce the financial load carried by thermal generators.
It is unclear if there was a formal answer from the government to the oil company's letter.
There was no immediate response from the Energy Ministry to requests for comment.
($1 = 3.585 reais)
Reporting by Luciano Costa and Marcelo Teixeira; Editing by Chizu Nomiyama and W Simon