The disaster in Japan and the instability around nuclear power plants has sent Australian uranium stocks tumbling.

Energy Resources of Australia, a Rio Tinto subsidiary, which owns Ranger Uranium mine in the Northern Territory, fell by 14 per cent on the stock exchange yesterday.

The picture is similar around the world. On the Johannesburg Stock Exchange, local uranium share prices fell by as much as 20 per cent.

Independent market analyst Peter Strachen says he believes it's a knee-jerk reaction.

"There are still quite a number of new power plants being developed in India, China, Brazil and elsewhere," he said.

"So I think this will basically blow over in the next 12 to 18 months, as people realise that there's no real alternative in the short to medium term, for large, baseload power supply."