Nuclear powerThorium holds promise of safer, cleaner nuclear power

Published 22 January 2013

Thorium as nuclear fuels has drawbacks, but its main advantage includes generating far less toxic residue. The majority of the mineral is used during the fission process, and it can burn existing stockpiles of plutonium and hazardous waste, saving the need to transport it and bury the waste in concrete. If thorium becomes available as a source of energy in the future, the world will rely less on coal and gas, and wind turbines will become a thing of the past. The risk of a global energy crunch will decrease considerably.

In the 1960s the Oak Ridge National Laboratory in Tennessee built a molten salt reactor which used liquid fuel, but it the project was stipped by the Nixon administration because the Pentagon needed plutonium residue from uranium to build nuclear bombs.

The blueprints for thorium sat in the archives until they were retrieved by NASA engineer Kirk Sorensen, who published them.

Jiang Mianheng visited the Oka Ridge labs and obtained the designs after reading an article on thorium energy in the American Scientist two years ago.

The Sydney Morning Herald reports that Mianheng is now leading a project for the Chinese Academy for the Sciences with a start-up budget of $350 million. Mianheng wants to stop the use of pressurized water reactors, which are fuelled by uranium, and use thorium reactors which produce far less toxic waste.

“China is the country to watch,” Bryony Worthington, head of Britain’s All-Party Parliamentary Group on Thorium Energy, recently told the Sydney Morning Herald.

“They are really going for it, and have talented researchers. This could lead to a massive break-through.”

Thorium energy can do for nuclear power what hydraulic fracking has done for natural gas, meaning cheaper energy with almost no carbon dioxide emissions.

China, Norway, and Japan are all currently looking into thorium energy.

According to Mianheng, China’s energy shortage is becoming “scary” and could pose a threat to national security in the near future. Disputes between India, Vietnam, the Philippines, and Japan over energy are quickly becoming threats to regional peace.

Mianheng’s team, which includes 140 scientists who are working full time, plan to build a two megawatt plant that uses liquid fluoride by the year 2020, before scaling up to a commercially viable size. Mianheng estimates that China has enough thorium  to support its electricity need for the next 20,000 years.

China plans on having twenty-six new conventional reactors within the next two years, and fifty-one more are planned, with 120 in the pipeline. The Herald notes that all these reactors will rely on imported uranium.

According to Robert Cywinski from Huddersfield University, who leads Britain’s thorium research networkThorEA, using thorium energy ensures that a situation like the Fukushima disaster cannot happen.

The metal  must be bombarded with neutrons to drive the process. “There is no chain reaction. Fission dies the moment you switch off the photon beam,” Cywinski told theHerald.

“People are beginning to realize that uranium isn’t sustainable. We’re going to have to breed new nuclear fuel. If we are going to the trouble of breeding, we could start using thorium instead, without introducing plutonium into the cycle,” Cywinski added

Thorium does have its drawbacks. .It has to be converted into uranium-233, it is fertile but not fissile, and the metallurgy is demanding. It can also be used as feedstock for bombs, although it is not easy to do so.

Its positives include the ability to leave far less toxic residue. The majority of the mineral is used during the fission process and it can burn existing stockpiles of plutonium and hazardous waste, saving the need to transport it and bury the waste in concrete.

If thorium becomes available as a source of energy in the future, the world will rely less on coal and,  gas, and wind turbines will become a thing of the past. The risk of a global energy crunch will decrease.