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Thorium technology although being used in some countries is no where as mature as Uranium tech. Efficiency is very low and procedure is costly. As of today, we are better off investing on uranium based reactors. But India is heavily investing in R&D for thorium reactors, because India has lots of reserves of Thorium.
In 15-25 years, we will finally have enough knowledge to put this thorium to use. That is the day I am waiting for.
A thorium fuel cycle offers several potential advantages over a uranium fuel cycle, including greater abundance on Earth, superior physical and nuclear properties of fuel, enhanced proliferation resistance, and reduced nuclear waste production.
The thorium fuel cycle, with its potential for breeding fuel without fast neutron reactors, holds considerable potential long-term benefits. Thorium is significantly more abundant than uranium, and is a key factor in sustainable nuclear energy. Perhaps more importantly, thorium produces one to two orders of magnitude less long-lived transuranics than uranium fuel cycles, though the long-lived actinide protactinium-231 is produced, and the amount of fission products is similar..
The mighty thorium
The nearly perfect energy source nobody has heard of
Sunday, March 7, 2010 2:56 AM
BY DOUG CARUSO
THE COLUMBUS DISPATCH
COURTESY OF KIRK SORENSEN
A look inside the thorium reactor, which was operated at Oak Ridge National Laboratory from 1965-69.
Craving reliable energy that doesn't come with a big side order of carbon, the United States is taking a new look at nuclear power.
But even as they hail President Barack Obama's announcement last month that the government would back $8 billion in loans for new nuclear power plants, some engineers also are urging a new look at an alternative to the uranium fuel those plants will inevitably use.
Thorium, they say, provides all the carbon-free energy of uranium - about 300 times more, actually - with almost none of the guilt.
Thorium plants cooled with molten fluoride salt would leave a fraction of the nuclear waste compared to the uranium-fueled, water-cooled plants in use today. In addition, thorium plants can't melt down and don't produce reliable fuel for bombs.
"What's not to love?" asked Kirk Sorensen, a NASA rocket scientist in Huntsville, Ala., who is earning his doctorate in nuclear engineering.
Sorensen has taken up the cause of thorium reactors, an idea conceived in the 1950s and last researched in the United States in the early 1970s at Oak Ridge National Laboratory in Tennessee.
And compared to coal?
"The amount of thorium it would take to power my whole life is the size of a marble that would fit in my hand," Sorensen said. "The amount of coal that would power my life would bury my yard to 30 or 40 feet."
The scientists who designed the first molten salt reactors at Oak Ridge were so far ahead of their time, Sorensen said, that "It's like a little moment of the 21st century was plucked out and plunked into the '50s."
So why aren't there thorium reactors all over the country?
Several nuclear scientists said the nation was simply too wedded to uranium when the Department of Energy cut funding to the Oak Ridge reactor research.
"It was demonstrated in a couple of test reactors here that it works and it works well," said Dan Ingersoll, senior program manager for nuclear technology programs at Oak Ridge National Laboratory.
"It was abandoned not because it was a bad idea. It was a matter of having limited resources at the national level and choosing a single technology."
In other words, given the investment the nation had already made in uranium enrichment and power plants, the government backed research into the next generation of more-efficient uranium reactors and took thorium off the menu.
Weapons had nothing to do with the decision, Ingersoll said. But at the height of the Cold War, uranium had another advantage over thorium: Uranium reactors produce plutonium, which makes much better bomb fuel.
India is pursuing thorium.
Both uranium and thorium are mined as ore and then separated from the rock. But thorium is four times more prevalent in Earth's crust than uranium.
"They have tons of thorium and almost no uranium resources," Ingersoll said. "To me, that's the compelling argument. We've already made the investment and we have no shortage of uranium."
Richard Denning, a professor of mechanical engineering at Ohio State University who studies the safety of nuclear reactor designs, agreed that uranium is a proven technology that is here to stay.
"Right now, we're so into the fuel cycle," he said. "There is enough uranium to fuel the next generation of plants, which will look much like the last generation."
Sorensen and others warn that if we don't invest in thorium, others will beat us to it. In addition to India, which is pursuing less-efficient, water-cooled thorium reactors, he said, the Czech Republic is exploring liquid fluoride thorium reactors similar to reactors tested at Oak Ridge.
"You don't have to be a superpower to do this," Sorensen said. "You could be a state to do this. If the state legislature of Ohio said 'We want to become the thorium state,' it could.
"A handful of engineers in the '50s did it."
In the Energy Policy Act of 2005, Congress called for next-generation nuclear reactors that would be highly economical, equipped with safety enhancements, have minimal waste, and be proliferation-resistant.
Al Juhasz, a senior engineer at the NASA Glenn Research Center in Cleveland, said that liquid fluoride thorium reactors could easily meet those goals.
He started out studying such systems as potential power plants for a moon base or a spacecraft. But he came to the conclusion that they could make a big dent in greenhouse gas emissions and energy needs right here on Earth.
Juhasz noted that it takes more than 300 tons of naturally occurring uranium to produce the same energy as 1 ton of naturally occurring thorium.
With the United States holding 16 percent of the world's thorium supply - about 1.4 million tons - he said, there is enough to power the country safely for thousands of years.
Thorium, the nearly perfect energy source no one has heard of | The Columbus Dispatch
