Posted Tue 31 Jan 2012 at 8:03pmTuesday 31 Jan 2012 at 8:03pmTue 31 Jan 2012 at 8:03pm, updated Tue 31 Jan 2012 at 8:14pmTuesday 31 Jan 2012 at 8:14pmTue 31 Jan 2012 at 8:14pm Hamaoka Nuclear Plant: Japan has 54 nuclear plants, but only a handful are operational.(ABC News) United Nations nuclear experts have backed Japan's efforts to prove its nuclear plants can withstand massive natural disasters