Watts Bar Unit 2 Nuclear Plant Completes Power Ascension Testing
The Tennessee Valley Authority (TVA) has reached another milestone in its effort to bring Watts Bar Unit 2 into commercial operation: The unit completed its final power ascension test—a 50% load rejection from full power—and safely returned to full power on September 30.
The testing had been halted on August 30 due to a switchyard transformer fire. Although the fire did not affect Unit 2’s systems, which responded to the event as designed, the affected transformer had to be replaced before testing could resume. The TVA said a rigorous and detailed inspection, repair, and testing process was performed before the transformer was returned to service on September 26.
Power ascension testing included more than 40 required tests at various power levels up to 100% output, with pauses at 30%, 50%, and 75% (Figure 1). The gradual increase in power provided data, which was used to verify that the unit was operating as designed.
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1. Watts Bar Unit 2 power ascension testing plan. |
