The cost of keeping uranium out of the hands of terrorists and safe from natural disasters is sidelining nuclear energy, which officials once dreamed would power a utopian future of cheap, almost limitless electricity.

The amount of power produced by nuclear reactors has dropped to a 32-year low, the International Atomic Energy Agency was to tell its 162 member states meeting in Vienna Monday. The agency was also to present lower forecasts for future output as governments in developed nations seek other sources of power.

Even as a new generation of campaigners promote carbon emission-free nuclear power as part of a strategy to tackle climate change, growth has stalled in Europe and North America while Japan's reactor network — the world's third biggest — remains idle following the March 2011 earthquake and tsunami that wrecked the Fukushima No. 1 atomic plant. Concerns that Iran, Syria, or even some terrorist group, might squirrel away fuel for making bombs have pushed up the price of nuclear power in the rest of the world.

"Where electricity markets are liberalized, nuclear is finding that it cannot compete on cost," said Edwin Lyman, a physicist at the Cambridge, Massachusetts-based Union of Concerned Scientists. "The biggest external cost of nuclear power stems from its potential to be misused for nuclear weapons."

It's all a far cry from the IAEA's origins in the 1950s when it was set up following President Dwight D. Eisenhower's appeal to the United Nations to promote the use of "Atoms for Peace."