The Nuclear Safety Council (CSN) said in a statement that it had approved a technical opinion regarding the renewal.
It said it has authorised Almaraz-1 to operate until 1 November 2027 and Almaraz-2 until 31 October 2028.
CSN said its decision was based upon technical reports and the requirements of laws governing the operation of nuclear facilities.
The ministry for ecological transition must now give final approval.
Almaraz-1 is a 1,011-MW pressurised water reactor unit that began commercial operation in September 1983. Almaraz-2, a 1,006-MW PWR , began commercial operation in July 1984.
Spain’s fleet of seven commercial nuclear power plants generated 21.43% of the country’s electricity in 2019, making it the leading source of generation, industry group Foro Nuclear said in January.
In February 2018 the Spanish government published a draft energy and climate plan for 2021-2030. The plan estimates the contribution of different technologies to the Spanish electric system every five years until 2030 and specifies that, at least until 2025, installed nuclear power will remain the same at around 7,400 MW. It will be reduced to 3,181 MW from 2030 onwards.
The plan – after comments from the European commission – was due to be approved before the end of 2019. However, it has not been updated since the November 2019 general election, in which the governing Socialists won the most seats, but fell short of a majority.