LUSBY, Md., Feb. 16, 2002 -- Operators at the Calvert Cliffs Nuclear Power Plant safely shut down the Unit 1 reactor at 11:55 p.m. Friday, Feb. 15 to begin a scheduled maintenance and refueling outage that encompasses the largest refurbishment project in the plant's history. The Unit 2 reactor continues to operate at full power.

The outage ended an outstanding operating run for Unit 1, which was last refueled in April 2000. The reactor had generated 7.4 million megawatt-hours of electricity, the most in its history, during that operating period.

Five years of in-depth planning and manufacturing of key components at facilities from Canada to Japan set the stage for the outage. More than a half-million man-hours will be invested in upgrades and tests focused on keeping the 850-megawatt unit generating electricity at high levels of safety, reliability and efficiency. New steam generators and main transformers will 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.

Unit 1's two new steam generators-massive 500-ton steel cylinders that use the reactor's heat to make steam to produce electricity-use a state-of-the-art design and materials that increase generating capability by slightly more than 1 percent. Unit 2's new steam generators will be installed when the reactor is refueled in 2003, completing the project.

Standard outage work includes replenishing about 40 percent of Unit 1's uranium fuel and testing and inspecting its turbine and safety systems.

Outage work will be performed by 1,200 Calvert Cliffs employees, specialists from other Constellation Energy Group organizations, and more than 1,400 contract workers from across the United States.

Calvert Cliffs produces approximately 1,700 megawatts of electricity, enough to meet the needs of more than a half-million homes, and provides about 20 percent of the electricity used in Maryland.

Calvert Cliffs is part of the Constellation Energy Group. Constellation Energy Group owns energy-related businesses, including a North American wholesale power marketing and merchant generation company and the Baltimore Gas and Electric Company (BGE), a regulated energy delivery company in Central Maryland. BGE provides service to more than 1.1 million electric customers and more than 600,000 natural gas customers in Central Maryland.

Constellation Energy Group had $3.9 billion in revenues in 2001 and assets of $13.7 billion at December 31, 2001.