Is thorium the missing piece of the energy jigsaw? Thorium is an element that is more abundant than uranium and can be used in nuclear reactors more safely than uranium. The advantages of relatively carbon free electricity generation by uranium are well understood, and so are the disadvantages.
There are three main disadvantages – the danger of a catastrophic accident is the first. There have been accidents with poorly designed nuclear reactors, like those at Chernobyl, and less dangerous accidents at reactors which have created radioactive discharges. Not many people have died, as far as we know, as a result of these accidents but the risks are very high and this involves a great deal of safety management.
The second disadvantage is that nuclear waste is dangerous and has to be processed safely and then stored for thousands of years. The storage has to be impeccably safe and with human beings history teaches us that it is impossible to guarantee safe storage for thousands of years. Certainly main controls can be put in place today to ensure safe storage as far as possible, but we do not know why some structures were built by humans thousands of years ago and we cannot be sure that humans will understand why nuclear storage facilities were built and why they should be maintained in five thousand years time. A lot happens in history.
The third disadvantage is the reason why the western countries seek to deny nuclear energy to states of which they are suspicious. Nuclear waste can be reprocessed into plutonium that is suitable for nuclear weapons. The process is not easy but certainly feasible enough for some nations wanting to stop other nations from building nuclear reactors. Nuclear weapons are the world’s major source of weapons of mass destruction, which get everyone excited a few short years ago.
So any nuclear energy argument has to address these three major disadvantages. Once the nuclear genie is out of the bottle it becomes hard to say that, for example, the western democracies will always use it safely or that autocratic and despotic regimes will always use it badly. We just do not know.
However, some of the arguments against nuclear reactors may become less imperative if we can use thorium instead of uranium. For a start you need less thorium to drive a power plant than uranium. Thorium produces around 250 times more energy per kilo than uranium so there will be a great deal less waste material created by a thorium power plant. Then you take into account that you cannot easily manufacture plutonium for weapons from thorium waste. It is theoretically possible but has not yet been done, as far as I know. That is a big advantage. Then, waste thorium material remains radioactive for “only” hundreds of years, as opposed to around 10,000 years that uranium remains radioactive.
Thorium is thought to be less inherently dangerous in a power plant than uranium. When a uranium-235 atom splits, it releases a wave of high-energy neutrons. These can then collide with other uranium-235 atoms, releasing more neutrons creating a potentially dangerous chain reaction.
If you use thorium, instead of uranium, you can start and stop the heat reaction by beaming protons on the material. This then becomes a simple way to shiut down a thorium reactor and a very safe process.
Creating a thorium reactor will require about half a billion pounds and around fifteen years of development work. Even if the money needed is two or three times as much if thorium can provide an important part of the world’s energy solution, someone should make a start on the research.
There seems to be a lack of political will; perhaps this inertia is compounded by the fact that we can get uranium supplies form places like Australia, where much of the world’s thorium is located in India. Using thorium would create some political change of energy power, but there seem ample supplies in nations like the United States and Australia.
Thorium was discovered 180 years ago by a Swedish chemist, Jons Jakob Berzeliu, who named the element for the Norse God of thunder, Thor. If the metal named for Thor can be subjected to a proper detailed trial to help us produce safer, low carbon energy, it certainly seems worth a worthwhile investment and the nation making the investment will have great advantage in the future.
Filed under: carbon emissions, climate change, energy, global warming, nuclear, nuclear energy Tagged: | advantages of thorium, chernobyl, disadvantages with nuclear, plutonium, sources of thorium, thoirum. thorium power plants, Thor