Tokyo Electric Power Company Holdings Inc. plans to start loading nuclear fuel into a reactor Monday at an idle plant northwest of Tokyo, as part of preparations to potentially restart the facility. The Nuclear Regulation Authority granted approval earlier in the day for the loading of the No.7 reactor at the Kashiwazaki-Kariwa plant in Niigata Prefecture. However, the timing of the restart remains uncertain. TEPCO has yet to restart any of its nuclear reactors, which were halted after the Fukushima Daiichi nuclear disaster triggered by the March 2011 earthquake and tsunami. The utility said i…