Romania's Cernavoda nuclear power plant (Image: Nuclearelectrica)

The work agreed with Cernavoda's owner, Nuclearelectrica, is worth CAD64 million (USD49 million) and covers engineering and early procurement for the retubing of the reactor core. Candu units are pressurised heavy water reactors designed to operate for 30 years, with a further 30 years available subject to refurbishment. This means the replacement of key components in the reactor core: fuel channels, pressure tubes and feeders.

As the holder of the original design, Candu Energy has taken part in this work several times before at the Darlington, Bruce and Point Lepreau plants in Canada, as well as Wolsong in South Korea and Embalse in Argentina. Candu Energy said it would be sending specialised staff to Romania, while Nuclearelectrica noted it had hired 100 people, some of whom would be spending time in Canada at Candu units that have already undergone this process.

"Romania needs renewed nuclear power capacities for producing clean, stable and affordable energy, as a solution for achieving energy security and the protection of consumers," said Cosmin Ghi??, CEO of Nuclearelectrica. He noted that Cernavoda 1 has met 9% of the country's electricity needs over its 25 years of operation so far while avoiding 125 million tonnes of carbon dioxide.

Romania's nuclear strategy

Nuclearelectrica plans to operate Cernavoda 1 until the end of 2026 and then undertake the refurbishment from 2027 to 2029. Once it is approved for restart by safety regulators, unit 1 should then operate until around 2060. The project therefore represents a major plank in Romania's policy to reach net-zero in terms of carbon dioxide emissions from 2050. The total cost of the refurbishment is estimated at EUR1.85 billion (USD1.85 billion).

Cernavoda 2 will also be a candidate for refurbishment, but it is nine years younger than unit 1 and would be due for this in 2037.

In parallel to refurbishments, Nuclearelectrica wants to complete and bring into service two half-built Candu units at Cernavoda, units 3 and 4. The first contracted work for this, with Candu Energy as well as Sargeant & Lundy, began in November last year. Unit 3 could be in operation by 2031.

A third aspect of Romania's nuclear power strategy relates to small reactors. Last year Nuclearelectrica signed agreements with NuScale towards the goal of bringing one of the US-based company's reactors online in 2028 at Doice?ti. It was recently announced that this would benefit from USD14 million in US federal support for front end engineering and design.