UPDATE 1-Lack of fuel may limit US nuclear renaissance -MIT

(Updates with Neff's comments, other details)

NEW YORK, March 21 (Reuters) - Limited supplies of uranium fuel for nuclear power plants may thwart the renewed interest in nuclear energy in the United States and other nations, according to an industry expert at the Massachusetts Institute of Technology.

Over the past 20 years, none of the nation's utilities has ordered a new reactor and there has been little investment in new uranium mines or facilities to produce fuel for existing reactors due to safety concerns.

Instead, the industry has lived off commercial and government inventories, which are nearly gone. Uranium production worldwide meets only about 65 percent of current reactor requirements.

"Just as large numbers of new reactors are being planned, we are only starting to emerge from 20 years of underinvestment in the production capacity for the nuclear fuel to operate them," Dr. Thomas Neff, a research affiliate at MIT's Center for International Studies, said in a release.

Only a few years ago, uranium sold for $10 per pound. The current price is over $90 a pound, according to the latest data from the Ux Consulting Co. LLC, of Roswell, Georgia.

Despite the higher prices, uranium year-on-year production actually declined in 2006 due to various problems at the mines.

Currently, much of the uranium used in the United States comes from mines in Australia, Canada, Namibia and Kazakhstan. Mines in the Western United States produce only a small amount of uranium.

The United States also relies on Russia for half its fuel under a "swords to plowshares" deal that Neff originated in 1991. This deal is converting about 20,000 Russian nuclear weapons to fuel for U.S. nuclear reactors, but it ends in 2013, leaving a substantial supply gap for the United States, Neff warned.