Small thorium reactors could lead to fossil-fuel-free world within five years

Georgia nuclear power plant faces hurdles,” 22 February 2010 HSNW).

Nuclear plants need fuel, though, which means building controversial uranium mines. Thorium, on the other hand, is so abundant that it is almost an annoyance. It is considered a waste product when mining for rare-earth metals.

Boyle notes that thorium also solves the nonproliferation problem. The Nuclear Nonproliferation Treaty (NPT) prohibits processes that can yield atomic bomb ingredients, making it difficult to refine highly radioactive isotopes. Thorium-based accelerator-driven plants, however, only produce a small amount of plutonium, which could allow the United States and other nations to promote nuclear power without running afoul of the NPT.

Evans-Pritchard says Obama needs a Roosevelt moment, recalling the famous breakfast meeting when Albert Einstein convinced the president to start the Manhattan Project.

Accelerator Driven Thorium Reactor at a glance

How does the ADTR power station work? The ADTR power station uses thorium as its main fuel. As a nuclear material, thorium is not fissile; it is described as “fertile” — which means that by capturing nuclear particles or neutrons it “breeds” or converts to a type of uranium which is able to react in a fission process and produce energy.

In order to provide these neutrons, initially a small amount of material is required along with the use of the accelerator which, through a process known as spallation, provides further neutrons. These spallation neutrons initiate the fission process that goes on to breed further uranium from the thorium.

Aker Solutions says the ADTR power station concept has the following benefits:

• Thorium is an abundant mineral deposit; there being 3 to 5 times more thorium in the world than uranium. More importantly, virtually all of the thorium mined can be used as fuel compared to only 0.7 percent of the uranium recovered in its natural state. Put simply, in energy terms, one ton of thorium mined is equivalent to 200 tons of uranium mined, which is equivalent to 3.5 million tons of mined coal.
• The concept incorporates intrinsic safety features which are fundamental to its design. A significant advantage of this type of process over conventional reactors is that the accelerator is the main source of reactor control; turn off the accelerator and the reaction reduces virtually instantaneously.
• The ADTR power station has proliferation resistance advantages compared to other reactor systems, specifically long fuel residence time mitigates material diversion, the degree of self-protection afforded by irradiated fuel and no enrichment process is needed. Additionally, there is no requirement for enrichment technology with the thorium cycle.
• Construction below ground means that the reactor is highly resistant to damage from aircraft impact.
• Actinides from a thorium reactor are 0.006 times the amount from a conventional reactor.
• The ADTR power station can be configured as an actinide “burner” reducing long term waste burden.