Tokyo Electric Power Co. via Reuters

The south side airlock double-entry doors are seen at Tokyo Electric Power Co. (TEPCO)'s Fukushima Daiichi nuclear power plant in this combination photo taken from the large equipment service entrance using a normal camera (top) and a gamma ray camera on May 20 and released by TEPCO on May 22. Gamma cameras are used to take images of gamma radiation.

TOKYO — Tokyo Electric Power Co reported a $15 billion net loss on Friday to account for the disaster at its Fukushima nuclear plant, marking the biggest loss in Japan by a non-financial company and prompting the firm to warn its future was uncertain.

Much-criticized president, Masataka Shimizu, 66, resigned to take responsibility for the worst nuclear crisis since Chernobyl in 1986, making way for an insider, managing director Toshio Nishizawa, 60.

Engineers are battling to plug radiation leaks and bring the plant northeast of Tokyo under control more than two months after a 9.0 magnitude earthquake and deadly tsunami that devastated a swathe of Japan's coastline and tipped the economy into recession. Continue reading.