Further scrutiny of isolation condensers at Fukushima Daiichi and another year of big losses for nuclear utilities highlighted the news from Japan this week.Recent developments related to the Tokyo Electric Power Co. reactors blacked out by the 2011 earthquake and tsunami include:NRA Sets Timeline for Safety Systems InvestigationJapan's Nuclear Regulation Authority used the first-ever meeting of its investigative panel to order an investigation at Fukushima that will be forwarded to the International Atomic Energy Agency, the Asahi Shimbun reported. Specifically, the investigations will follow up on NRA promises made in February to study isolation condensers in unit 1, which TEPCO maintains were undamaged by the earthquake but that the Japanese government has sought to know more about as it establishes new seismic requirements for nuclear plants. The NRA will also look into other contentious areas of the accidents, including the source of a hydrogen explosion in the reactor building of unit 4, which was offline at the time of the tsunami. The work is due at the end of the year and will likely be incorporated into a larger IAEA investigation scheduled for completion in 2014.More Yearly Losses for Japan's UtilitiesOnly two of Japan's ten regional power companies posted profits for the fiscal year that closed at the end of March, the Asahi reported Wednesday. The rest reported combined losses of $16 billion for 2012, driven by fossil fuel costs for replacement power and the ongoing maintenance of idled reactors. Government-rescued TEPCO took the biggest hit, with a $7 billion loss fed in part by growing accident settlement claims.Photo: Workers on April 26 remove a pipe used to guide a camera into the primary containment vessel of unit 2 after searching for the exact locations of water leaks.