Cernavodă nuclear reactor to reconnect to grid this week after three-month shutdown

Nuclear energy producer Nuclearelectrica announced that it started procedures to reconnect Unit 1 of the Cernavodă Nuclear Power Plant after the minimum required conditions were met. The reactor is expected to be synchronized with Romania’s national electricity grid on Friday, November 6, following a shutdown of more than three months.

Unit 1 was taken offline in a controlled procedure on July 28 because of the severe drought and low Danube water levels. The river’s flow has increased in recent days, allowing the company to begin the reconnection process.

“The start of Unit 1’s reconnection procedures, following the fulfillment of the minimum conditions for fully safe synchronization, is an important step,” Nuclearelectrica CEO Mihai Gioară said. “Synchronizing Unit 1 with the National Energy System is necessary to ensure energy security and system stability.”

Nuclearelectrica said reconnecting a nuclear reactor was a complex and strictly regulated operation carried out under nuclear safety requirements.

Unit 1 requires large volumes of cooling water, and its operation will lower the water level in the plant’s intake basin. As a result, Unit 2 can only be restarted if the Danube’s water level continues to rise, the company explained.

Unit 2 has remained offline since August 13, when it was also shut down because of the drought. Once sufficient conditions are met, it will be restarted and subsequently synchronized with the grid.

The Cernavodă plant operates two reactors, each with an installed capacity of 700 MWe. Together, they normally account for approximately 20% of Romania’s electricity production.