Calvert Cliffs Nuclear Power Plant


The Calvert Cliffs Plant at Lusby, Maryland has 2 Combustion Engineering PWR units with ~800 MWe generators. Calvert Cliffs is the first US plant authorized for renewal of the operating license past 40 years. 

The Screenhouse is shown in the foreground, substation in the background. This facility is owned/operated by Baltimore Gas & Electric.

Courtesy EEI -Electric Perspectives

A number of simplified diagrams illustrate the the design of this pressurized water reactor plant. Although these diagrams were provided by Westinghouse, they are representative of the Combustion Engineering design. A major difference between the two designs is that Combustion Engineering plants have 2 reactor coolant pumps per loop, whereas Westinghouse plants have 1 reactor coolant pump per loop. The original Combustion Engineering design also made more use of computer-based systems in the reactor protection system which automatically shuts down the plant. For more on the PWR Cycle.

In each reactor, 217 fuel assemblies of the 14x14 design are used with 176 fuel rods per assembly. The containment is a large steel structure rated at 50 psi pressure.Each reactor coolant loop has 1 U-tube vertical steam generator and 2 reactor coolant pumps. Each unit has a pressurizer connected to one of the 2 loops. Normal makeup water is provided by 1 of 3 Chemical and Volume Control System charging pumps rated at 44 gpm and 2500 psi.

On the non-radioactive secondary side of the steam generators, condensate-feedwater is supplied by 3 condensate pumps, then 3 condensate booster pumps, and 2 turbine-driven feedwater pumps which move the water from the condenser to the steam generators. Pressure and temperature are raised from vacuum and 90F to 1100 psi and 425 F.

Emergency equipment for each unit include:

See the US plant address, plants, and map pages for more information.


Copyright 1996-2006.  The Virtual Nuclear Tourist. All rights reserved. Revised: January 11, 2006.