▁than ▁ 2   percent , ▁and ▁are ▁achieved ▁by ▁implementing ▁en hanced ▁techniques ▁for ▁calculating ▁re actor ▁power . ▁This ▁involves ▁the ▁use ▁of ▁state - of - the - art ▁feed water ▁flow ▁measurement ▁devices ▁to ▁more ▁precisely ▁measure ▁feed water ▁flow , ▁which ▁is ▁used ▁to ▁calculate ▁re actor ▁power . ▁More ▁precise ▁measurements ▁reduce ▁the ▁degree ▁of ▁uncertainty ▁in ▁the ▁power ▁level , ▁which ▁is ▁used ▁by ▁anal yst s ▁to ▁predict ▁the ▁ability ▁of ▁the ▁re actor ▁to ▁be ▁safely ▁shut ▁down ▁under ▁post ulated ▁accident ▁conditions . ▁Because ▁the ▁re actor ▁power ▁can ▁now ▁be ▁calculated ▁with ▁much ▁greater ▁accuracy ▁than ▁with ▁the ▁old ▁vent uri ▁type ▁measurement , ▁the ▁plant ▁can ▁safely ▁run ▁within ▁a ▁t ighter ▁margin ▁of ▁error ▁to ▁its ▁limits . ▁The ▁new ▁flow meter ▁works ▁by ▁comparing ▁the ▁time ▁it ▁takes ▁ul tr ason ic ▁sound ▁p uls es ▁to ▁travel ▁up stream ▁versus ▁down stream ▁inside ▁the ▁pipe , ▁and ▁uses ▁the ▁time ▁differential ▁to ▁figure ▁the ▁flow ▁rate ▁of ▁the ▁water ▁in ▁the ▁pipe . ▁ ▁The ▁N RC ▁approved ▁Vog t le ' s ▁License ▁Am end ment ▁Request ▁( L AR ) ▁in ▁March   2 0 0 8 . ▁The ▁N RC ▁staff ▁determined ▁that ▁Southern ▁N uc lear ▁could ▁safely ▁increase ▁the ▁re actor ' s ▁power ▁output ▁primarily ▁through ▁more ▁accurate ▁means ▁of ▁meas uring ▁feed water ▁flow . ▁N RC ▁staff ▁also ▁review ed ▁Southern ▁N uc lear ' s ▁evalu ations ▁showing ▁that