Exelon has launched a series of planned power uprates across the company’s nuclear fleet that will generate between 1,300 MW and 1,500 MW of additional generation capacity—equal to a new reactor—within eight years.
Exelon operates the nation’s largest fleet of nuclear reactors. The company’s 17 reactors produce some 20% of the nuclear power generated in the U.S. A series of plant upgrades and uprates have already added approximately 1,100 MW over the past 10 years, Exelon said.
The first nuclear 38-MW uprate was confirmed following equipment upgrades at the company’s Quad Cities nuclear plant near Cordova, Ill. Uprate projects are also under way at Exelon’s Limerick and Peach Bottom nuclear stations in Pennsylvania and the Dresden, LaSalle, and Quad Cities plants in Illinois. Those are expected to produce nearly a quarter of the new megawatts. The remainder of uprate megawatts will come from additional projects at nine Exelon plants beginning in 2010 and ending in 2017.
The uprate projects, overseen by the Nuclear Regulatory Commission (NRC), use a variety of technologies. These include:
- “Measurement uncertainty recapture” (MUR) uprates, in which more accurate metering allows more precise reactor operations and more electrical output. MUR uprates increase reactor thermal power and require NRC approval.
- Extended power uprates, in which reactor power can be safely increased by up to 20% after careful, rigorous analysis, equipment upgrades, and NRC approval.
- Generator rewinds, in which replacing certain generator components with new copper makes it possible for the generator to produce more electricity. Power plants will continue to meet all NRC license basis requirements.
- Turbine retrofits, in which advanced technology has allowed production of new and better shapes and sizes of turbine parts, such as blades, rotors, and casings. These new parts make the turbines more efficient, akin to improving the gas mileage on an automobile by using computer-controlled fuel injection rather than a carburetor.
In addition to producing more megawatts, these component upgrades improve the reliability of the units and support operating license extensions, which require extensive review of plant equipment condition, Exelon said. Exelon Nuclear President and Chief Nuclear Officer Charles Pardee added that they would also be a critical component of “Exelon 2020”—the company’s plan to eliminate the equivalent of its 2001 carbon footprint by 2020.