Catawba Nuclear Power Station

The Catawba nuclear power station is a 2.3GW nuclear power plant (NPP) located at Lake Wylie on the Catawba River, County, South Carolina, US.

Operating at a load factor of more than 86% since 1985, the facility produced approximately 567TWh of electricity as of 2018, with its two reactors.

The Catawba nuclear power station is jointly held by three municipalities, namely the North Carolina Municipal Power Agency Number One (NCMPA1), North Carolina Electric Membership Corporation (NCEMC), Piedmont Municipal Power Agency (PMPA), and Duke Energy Corporation.

Duke Power, a subsidiary of Duke Energy, is the operator of the Catawba NPP, which is capable of powering approximately 1.4 million US households.

The Catawba-1 reactor unit completed 30 years of clean and reliable energy generation in June 2015, while the unit two accomplished the same in August 2016.

The US Nuclear Regulatory Commission (NRC) approved Duke Energy’s request to increase the generating capacity of Catawba-1 by 1.7% in May 2016.

Catawba-1 and Catawba-2 are expected to be operational until 2043.

Catawba nuclear power station history

Construction of the Catawba NPP was started in May 1974. The Catawba-1 generating unit was commissioned in June 1985, while the second unit was commissioned in August 1986.

Both the reactors at the Catawba nuclear energy facility were  issued 40-year operations license by the NRC at the time of commissioning.

NRC, however, extended the operating licenses of both the units for another 20 years until 2043, in 2003.

Environmental review for a 60-year operation period of the nuclear power plant was conducted by the NRC, prior to the license renewal.

Catawba nuclear power station site details

The Catawba nuclear power plant site lies approximately 29km south-west of Charlotte, the commercial hub of North Carolina, and approximately 10km south of the town of Rock Hill.

It is situated approximately 48km south-west of the McGuire nuclear power plant, which has been operational since 1981.

Catawba nuclear reactor details

The Catawba NPP consists of two four-loop pressurised water reactor (PWR) units of 1,145MW net design capacity each, supplied by Westinghouse.

The nuclear fuel core of each unit comprises 193 fuel assemblies with each assembly featuring 264 fuel rods. Further, each 12ft-tall fuel rod encloses 272 Uranium pellets with each pellet measuring less than one inch long.

The fuel core is enclosed within a 44ft-long and 14ft-diameter reactor vessel with 8in-thick steel wall, which is placed within a containment building with 3ft-thick concrete walls and 0.75in steel lining.

Catawba NPP infrastructure facilities

The primary infrastructure facilities of the Catawba nuclear power plant include two reactor buildings, two turbine buildings that house a GE steam turbine generator each, an auxiliary building, a shared service facility, and two diesel generator building,  besides six mechanical draft cooling towers.

Common facilities for the two generating units are the water intake and discharge structures, and the standby nuclear service water pond.

The water required for the nuclear plant operations is sourced from the Lake Wylie, which extends for 45km between the Wylie Dam and the Mountain Island Dam.

Both the units of the Catawba nuclear power generation facility are fitted with additional pumps and back-up electrical supply system for emergency.

Power transmission

The electricity generated by the Catawba nuclear power station is evacuated to the grid through transmission network by means of five 230kV double-circuit overhead transmission lines from the switchyard located onsite.

The transmission lines originating from the Catawba NPP are the 17.5km-long Catawba-Allen transmission line, the 39.3km-long Catawba-Rip transmission line, the 2.1km-long Catawba-Pacolet line, and two 8.4km-long Catawba-Newport transmission lines.