True Alternative Energy: The Power Of Thorium
One of the best kept secrets regarding alternative energy sources is based on an element most people have never heard of—thorium. Named after the Norse god of thunder, Thor, thorium is a fertile (not fissile) fuel that can power safe nuclear reactors to provide almost unlimited amounts of emissions free power. At the same time, such reactors can also burn up existing stockpiles of nuclear waste. For various political reasons thorium has not found support in countries like the US, but now a Norwegian company is making the switch from uranium to thorium, running one of its power reactors for a four year test to prove the viability of this true source of clean alternative energy. Norway, like the US and many other countries, have abundant supplies of this element—perhaps it is time to actually solve the world's energy problems for the foreseeable future, without all the expensive solar cells and bird killing wind turbines.
Thorium was discovered in 1828 by the Swedish chemist Jons Jakob Berzelius who named it after the Norse god of thunder, Thor. Found in trace amounts in rocks and soil world wide, thorium is three times more abundant than uranium. It is found on the periodic table of elements with other dense, radioactive substances, including uranium and plutonium, known as actinides. Thorium is a lustrous silvery-white metal that is only slightly radioactive. One of the most attractive things about thorium is that it cannot be used to make atomic bombs—but it can be used to power nuclear reactors. Currently, Norway is conducting a multi-year test of thorium in an existing reactor.
According to Singularity Hub, Oslo based Thor Energy is teaming with the Norwegian government and US-based (but Japanese/Toshiba owned) Westinghouse to begin a four year test that they hope will “dispel doubts and make thorium the rule rather than the exception.” The thorium test will take place at the government reactor in Halden, which is no stranger to experiments in nuclear energy technology.
The Halden Reactor Project has been in operation since 1958 and is the largest Nuclear Energy Agency (NEA) joint project, supported by more than 130 organizations from 19 countries. It brings together an important international technical network in the areas of nuclear fuel reliability, integrity of reactor internals, plant control/monitoring and human factors. The program is primarily based on experiments, product developments and analyses carried out at the Halden Nuclear Reactor.
Halden, one of Norway's two reactors, is a conventional Boiling Water Reactor which has been used in the past for fuel stability testing. In this test some of the fuel rods that normally contain uranium are replaced by thorium rods so they undergo the thorium fuel cycle. As neutrons from the nuclear reaction bombard the thorium, 232Th, it is transmuted into the fissile, artificial uranium isotope 233U, by way of a short lived isotope of protactinium, 233Pa. This transmuted uranium is then consumed by the reactor like normal uranium fuel.
Thor Energy AS has previously evaluated the possibility of utilizing Norway’s thorium deposits and completed a 2-year thorium fuel cycle feasibility study. That study concluded that thorium-based nuclear fuel has several advantages over uranium-based fuel. These include better waste characteristics, improved proliferation resistance, and abundant raw material supply.
Building on that work, Thor Energy has established a consortium that is conducting a 5-year thorium irradiation project at the Halden site, which started at the beginning of 2012. Thor Energy is owned by Thor Corporation a holding company which also has shares in businesses related to thorium fuel, thorium mining and separation of rare earth elements.
One previously developed technology, the liquid thorium fuel reactor with molten salt coolant, is re-emerging as a potentially safe, cost-effective solution to future energy needs. Known as the Liquid Fluoride Thorium Reactor (LFTR), it is being championed by the Energy From Thorium Foundation. According to them, thorium is abundant, produces far less toxic fission products than uranium and may soon compete with coal for cost per kilowatt-hour. “The chemistry of thorium fission is compelling, and the engineering of thorium reactors, with a longer history than most people realize, appears to be seductively manageable,” their website states.
Some are skeptical. The UK’s Department of Energy & Climate Change released a report that stated: “thorium has theoretical advantages regarding sustainability, reducing radiotoxicity and reducing proliferation risk. While there is some justification for these benefits, they are often overstated.”
Acknowledging that their report “should be seen as a preliminary analysis of technological potential and are not intended as an exhaustive review,” they go on to acknowledge that worldwide interest in thorium is likely to remain high and they recommend that the UK maintain a “low level” of research and development into thorium fuel. None the less, other countries are pressing ahead with field trials of thorium reactors.
India and China are particularly interested in thorium as a fuel. According to a report in New Scientist, India is pressing ahead with plans to utilize its abundant supplies of thorium:
Last week, the Nuclear Power Corporation of India (NPCIL) put out statements to the Indian press touting the safety of its new Advanced Heavy Water Reactor (AHWR), which could break ground near one of the country's conventional reactors next year. Once operational, they claim it will fulfil the vision of India's 60-year-old blueprint for thorium-based nuclear energy production, generating 300 megawatts of power from thorium more safely than nuclear energy has ever done. NPCIL's technical director, Shiv Abhilash Bhardwaj, told the press that such reactors will be so safe they can be built right inside major cities like Mumbai.
In January 2011, despite an active uranium reactor building program, the Chinese Academy of Sciences (CAS) announced a $350 million 5 year thorium MSR project engaging 400 people. Jiang Mianheng, son of former president Jiang Zemin and a leader of the CAS, gave the lead-off presentation at the International Thorium Energy Organization 2012 meeting in Shanghai, a conference sponsored by the Shanghai Institute of Nuclear and Applied Physics and the CAS. His speech confirmed China's intense interest in the LFTR concept and thorium in general.
With most other energy resources in high demand and limited supply, thorium is thought to be quite abundant and distributed world wide. In terms of crustal abundance it is about 3.5 times as abundant as uraninum. The 2007 IAEA-NEA publication Uranium 2007: Resources, Production and Demand (referred to as the 'Red Book') gives a figure of 4.4 million tonnes for total known and estimated resources. But the report acknowledges that the by country amounts account for only 72% of known resources and that excludes data from much of the world. Data for reasonably assured and inferred resources are given in the table below.
|Country||Tonnes||% of total|
The figures above should only be used for judging relative national resources. The Red Book estimated total for thorium of 6.08 million tons only slightly exceeds its 5.5 million ton estimate for uranium. It should be noted that the recovery cost for thorium is <$80 per ton while for uranium it is <$150 per ton, almost double the cost. Given that thorium is more a abundant element, and that it has not been aggressively searched for like uranium, it is reasonable to assume that proven reserves would rise sharply if thorium becomes widely used as an energy source.
If thorium is so fantastic why isn't it in wide use already? There have been prototype reactors built in the past. A pair of reactors operated in Germany between 1983 and 1989, and three operated in the US between the late sixties and early eighties. Alas, all of these plants were abandoned. In the US, the military was not interested in “safe” atomic reactors, they wanted the enriched uranium and plutonium produced by uranium fueled reactors for use in weapons. The world's largest consumer of civilian nuclear power turned its back on thorium because it did not produce dangerous enough waste products.
Be safe, enjoy the interglacial and stay skeptical.