Laser enrichment could cut cost of nuclear power

By Richard Macey
May 27, 2006

NUCLEAR power could become significantly cheaper thanks to world-leading laser technology being developed in Sydney.

A team of about 25 scientists, engineers and technicians at Lucas Heights, home of Australia's only atomic reactor, has succeeded where other nations, with budgets stretching into billions of dollars, have failed.

After a decade of work they have tested a new way to process, or enrich, the uranium needed to drive power plants.

The technology, said Michael Goldsworthy, a nuclear scientist and leader of the project, may halve enrichment costs, which he estimated accounted for 30 per cent of the price of nuclear fuel.

Power stations are fuelled by a specific blend of two types of uranium. About 5 per cent must be uranium 235, with the rest made from uranium 238. But natural uranium is 0.7 per cent U-235 and 99.3 per cent U-238.

There are at present only two methods for sifting uranium atoms, or isotopes, to create the right mix. One, called diffusion, involves forcing uranium through filters. Being lighter, U-235 passes through more easily and is thus separated from its heavier counterpart. The second method, widely adopted in the 1970s, uses centrifuges to spin the heavier and lighter atoms apart.

Both, said Dr Goldsworthy, are "very crude. You have to repeat the process over and over," consuming enormous amounts of electricity. The spinning method requires "thousands and thousands of centrifuges".

The Lucas Heights team, working for Dr Goldsworthy's research company Silex (Separation of Isotopes by Laser Excitation), is the only one in the world developing a third technique that involves streaming uranium through lasers tuned to a frequency that only "sees" the U-235 atoms.

The lasers electrically charge the atoms, which become trapped in an electromagnetic field and drawn to a metal plate for collection. "It's absolutely cutting-edge technology, incredibly difficult to develop," Dr Goldsworthy said.

During the 1980s and '90s the US, France, Britain, Germany, South Africa and Japan attempted to develop laser-enrichment technology, but all failed. One US effort involving 500 scientists gave up after spending $2 billion.

"By world standards, we have worked on a shoestring budget," Dr Goldsworthy said, estimating the "more elegant and sophisticated" Australian concept at about $65 million.

This week Silex, which has no government funding, signed a deal giving General Electric the rights to commercialise the technology. The first laser-enrichment plant will be built in the US, but others could follow in Australia.

Dr Goldsworthy hopes that in 20 years the laser technology could be enriching a third of the world's power station uranium, returning "handsome royalty streams" to Australia.

Asked if the Federal Government, which this week speculated Australia could "value-add" mined uranium through enrichment, was aware of his team's progress, Dr Goldsworthy said that, due to regulation, "we report to the Government regularly".
