Calvert Cliffs 1 shut down on February 15 to begin the largest refurbishment project in the plant’s history.

The outage marks the end of five years of planning and manufacturing of components, including new steam generators and main transformers to replace original equipment dating to start-up in 1974. Key components of the electrical generator will be replaced, a section of the cooling system will be upgraded with new high-strength tubing, and the reactor will undergo extensive inspections.

The two new steam generators will increase generating capability of the 835MWe unit by slightly more than 1%. New steam generators at the 840MWe unit 2 will be installed when the reactor is refuelled in February 2003, completing the project.

Outage work will be performed by 1200 Calvert Cliffs employees, specialists from other Constellation Energy Group organisations, and more than 1400 contract workers from across the USA. Standard outage work includes replenishing about 40% of the unit’s fuel and testing and inspecting its turbine and safety systems. The company expects the outage to last about 90 days.

The last time unit 1 shut for refuelling was from 10 March to 18 April, 2000, while unit 2 last refuelled between 16 March and 14 May, 2001.