Since the 11 March Fukushima catastrophe, nuclear energy companies worldwide have been pummeled by the new market realities, as more and more countries turn away from nuclear power.

Australia’s uranium reserves are the world’s largest, with 23 percent of the global total. Australia, Kazakhstan and Canada are the world’s top three producers, together accounting for 63 percent of world uranium production.

Rio Tinto’s locally listed uranium subsidiary, Energy Resources of Australia, has slashed uranium reserves by 46 percent and shelving a planned expansion, The Australian newspaper reported.

The Darwin-based ERA has also reported a January-June 2011 net loss of $121.75 million, down from a $22.7 million profit a year earlier. Contributing factors for the loss include disappointing first-half production figures from its Ranger uranium mine after heavy rains stopped operations as well as uncertainty over the immediate future of uranium markets in the wake of the Fukushima nuclear disaster.

ERA's share price fell sharply to its lowest close since 2004 following its downgrading of estimated reserves at its key Ranger uranium mine in the Northern Territory from 29,800 tons to 16,000 tons, which wiped $99 million of inventory value from ERA’s balance sheet.

ERA stock has fallen 70 percent in the past year, representing a $1.3 billion loss for Rio, which has a 68.4 percent stake in ERA.