Atucha 2 achieves first criticality

04 June 2014

Just days after receiving a licence allowing nuclear operations to begin, Argentina's Atucha 2 has achieved a sustained chain reaction.

Atucha 2 first criticality 460  (Ministry of Planning)
Planning minister de Vido and NASA president Antunez, centre, watch as the reactor reaches criticality (Image: Ministry of Planning)

The 745 MWe pressurized heavy water reactor (PHWR) achieved first criticality yesterday at 9.02am, the Ministry of Federal Planning reported. Minister of planning Julio de Vido was in the unit's control room to witness the milestone being met, together with president of Nucleoeléctrica Argentina SA (NASA) Jose Luis Antunez.

The issuance of a licence by the Autoridad Regulatoria Nuclear allowing nuclear operations to begin at the unit was announced on 29 May. On the same day, de Vido ceremonially launched the process to fill the reactor with borated heavy water. The neutron-absorbing boron has since been gradually extracted from the heavy water allowing the controlled nuclear chain reaction to occur.

Grid connection is expected soon, after which tests will be conducted at different power levels to verify the performance of the systems to reach commercial operation.

Antunez was quoted by the Telam news agency as saying, "We will complete tests already planned, then connect at 5% of power, and later take it to 30%, 50%, 70% and 100% and by year-end will be operating at full power." He noted that the unit will meet at least 4% of Argentina's annual demand for electricity.

The program to build Atucha 2, originally a Siemens-designed PHWR, was suspended in 1994 after 13 years of construction work. The project was revived after a 2006 government decision to complete the plant as part of a $3.5 billion strategic plan for the country's nuclear power sector, and the reactor design is unique to Argentina.

Atucha 2 is Argentina's third nuclear power plant, joining the 335 MWe Atucha 1 PHWR, which has been in operation since 1974, and the 660 MWe Embalse PHWR, operating since 1983.

Researched and written
by World Nuclear News