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Thorium: Upgraded and Extended BY DANNY RITT, CLASS OF 2013



Even though nuclear energy provides the United States with around twenty percent of its national electricity, no new nuclear construction has broken ground since 1977. While U.S. nuclear energy industry is seemingly at a standstill, India has created a plan based off of nuclear-produced electricity that utilizes domestic resources to supply a great majority of its increasing energy demand. What gives? It turns out that nuclear development in using the element thorium is what has allowed India to set their sights on energy independence. In turn, this pioneering effort should set an example for countries looking to improve their domestic energy production. As a matter of background, there are three nuclear isotopes that are “fissile,” which essentially means that they are capable of sustaining a nuclear reaction – uranium-233 (U233), uranium-235 (U235), and plutonium-239 (Pu239). In a nuclear fission reactor where U235 is often used, it absorbs an extra neutron into its nucleus and produces

an unstable compound that quickly decays to a more stable form by splitting apart and producing ionizing particles. The resulting particles carry an immense amount of kinetic energy to the atoms with which they interact, causing ionizations and a chain of subsequent nuclear reactions. Eventually, the transferred energy would appear in the form of heat in surrounding materials. In the reactor complex, this heat is used to then steam power turbines that ultimately produce electricity. Nuclear fission is appealing in that it is a self-sustaining method of producing huge amounts of energy. Ordinary chemical reactions involve energy levels on the order of single electron volts, but on the other hand, nuclear reactions involve energy levels on the order of millions of electron volts. One can thus see why nuclear reactions have an important place in energy production. Unfortunately, even while nuclear energy is utilized globally because of its potential, the current production capacity of nuclear reactors is limited by the fact that they only run on only uranium or plutonium for its energy producing fuel. Enter thorium. It would seem counterintuitive at first to consider thorium as a solution to uranium and plutonium shortages since thorium is a “fertile” material, meaning that it has to be used with a nuclear driver isotope to kick-start the nuclear reaction. So why bother with it? The main reason is that thorium is capable of producing U233, a very efficient fissile material, when reacted with nuclear drivers. This process is called transmuting and is accomplished by adding neutrons to an element and creating a new element in the process. In addition, thermal reactors are able to produce more U233 than the U235 and Pu239 material they

PSR- Issue 02-online version  
PSR- Issue 02-online version