by Dr Inkerman
Since the early 1990s Russia has had a program to develop a thorium-uranium fuel. Their research in more recent times has moved to having a particular emphasis on the utilization of weapons-grade plutonium in a thorium-plutonium fuel for the use in current reactors.
A Safe and cheap nuclear option Accelerator-driven systems (ADS)
ADS systems use a particle beam to feed the nuclear reaction and without the beam the reaction stops.
For many years there has been interest in utilizing thorium (Th-232) as a nuclear fuel since it is three times as abundant in the earth's crust as uranium and also, all of the mined thorium is potentially useable in a reactor, compared with the 0.7% of natural uranium. Some 40 times the amount of energy per unit mass should be available compared to uranium. This means that the carbon costs as well as the environmental damage from the mine is reduced significantly. No expensive enrichment process or facilities are needed farther reducing the carbon equation.
ADS reactors are safer than a normal fission reactor because they are subcritical and stop when the input current is switched off.
Thorium fuel may be mixed with long-lived wastes from conventional reactors to incinerate them.
Thorium cannot be used to produce weapons but it can be used to destroy them.
Thorium subcritical nuclear reactor will be able to convert all transuranic(long lived) elements into (generally) short-lived fission products and yield some energy in the process. Much of the current interest is in the potential of ADS to burn weapons-grade plutonium.
Ultimately the burning of the transuranic wastes including plutonium means that overall radiotoxicity is reduced greatly by 1000 of years, and is less than that of the equivalent uranium ore.
Mr Grae from Kurchatov Institute in Moscow believes mixed thorium fuels can not only dispose of weapons-grade plutonium, but also be developed into a fuel for many conventional reactors this would prevent production of any further plutonium as a by-product. The Russians are running thorium fuel in their IR-8 research reactor and are hoping to test in a full-size commercial nuclear power plant in Russia in 2008.
CERN PARTICLE LAB Geneva.
Released a detailed report covering the financial viability of the ADS design for power generation, and found it to be at least three times cheaper than coal and 4.8 times cheaper than natural gas.
The lack of promotion of this technology is because it is currently the only threat to the American nuclear arsenal. As the worlds supplies of plutonium are burnt in mixed fuel reactors an economic need for plutonium would drive the dismantling of Americas as well as other global nuclear weapons stockpiles in the need for fuel.
The current renewable energy push will contribute to the future of power in big ways and we need to promote it as much as possible but at the same time be aware that the consequences of renewals will be a large unnecessary increase in power price and the continued lining of corporate pockets. We have a once in a lifetime chance to take back our right to public power and a better world.
The increasing need for power is undeniable and despite all the good intentions a choice will have to be made coal powered carbon sequestration or nuclear power. It is most important that if the nuclear option is taken it is thorium based not uranium. I believe that we must lobby to remove funding from carbon sequestration and for it to be put into ADS thorium.
Boldeman, J.W., 1997, Accelerator driven nuclear energy systems, AATSE symposium "Energy for Ever".
Arkhipov, V., 1997, Future Nuclear Energy Systems: generating electricity, burning wastes, IAEA Bulletin 39/2/97
Treulle, H. 2002, The answer is No - Does transmutation of spent nuclear fuel produce more hazardous material then it destroys?, Radwaste Solutions July-August.
Nucleonics Week 7/11/96.
Euradwaste summary 3/2/00.
Bertel, E. et al 2003, P&T: A long-term option for radioactive waste disposal? NEA News 20.2.
COSMOS Magazine Issue 8 April 2006