Engineering tests during the initial operation of the peach bottom HTGR

The initial power operation of the Peach Bottom Atomic Power Station was programmed as a series of physics, engineering and chemistry tests. These were performed in the first half of 1967 and were successful in bringing the reactor to full power in carefully measured stages which assured both safety and complete verification of earlier design predictions. The steam generators required modifications during these tests but successfully produced design capacity at the design steam conditions of 1000°F at 1450 psig. The plant controls met design requirements of controlling these values closely at steady state and at load change rates of up to three per cent per minute, with the reactor and steam generators following turbine load demand. Plant safety actions (scram, setback, loop isolation) were also tested and proved to be much gentler than originally predicted. The overall plant produced a maximum of 44.5 MW(e) gross (40.0 MW(e) net) with a maximum measured efficiency of 38.7% gross (34.7% net), believed to be the highest nuclear power plant performance yet achieved. Main coolant gaseous activity has remained well below 1 Curie total and all the chemical impurities are well below design limits; less than 10 ppm total oxidants. Power production continued through 1967 with periodic testing and maintenance operations requiring occassional shutdowns.