Uranium depletion
Encyclopedia
Uranium depletion is the result of extracting and consuming uranium, a non-renewable resource
. The availability of high-grade uranium ore will deplete over time meaning the fuel will become more environmentally and economically expensive to extract.
, Canada
, Kazakhstan
, South Africa
, Brazil
, Namibia
, Uzbekistan
, USA, Niger
, and Russia
Out of those Canada
(28% of world production) and Australia
(23%) are the major producers. In 1996, the world produced 39,000 tonnes of Uranium. And in 2005, the world produced a peak of 41,720 tonnes of uranium, although the production continues to not meet demand.
Various agencies have tried to estimate how long these primary resources will last, assuming a once-through cycle. The European Commission said in 2001 that at the current level of uranium consumption, known uranium resources would last 42 years. When added to military and secondary sources, the resources could be stretched to 72 years. Yet this rate of usage assumes that nuclear power continues to provide only a fraction of the world’s energy supply. If electric capacity were increased six-fold, then the 72-year supply would last just 12 years. The world's present measured resources of uranium, economically recoverable at a price of 130 USD/kg according to the industry groups Organisation for Economic Co-operation and Development
(OECD), Nuclear Energy Agency
(NEA) and International Atomic Energy Agency
(IAEA), are enough to last for "at least a century" at current consumption rates. According to the World Nuclear Association
, yet another industry group, assuming the world's current rate of consumption at 66,500 tonnes of Uranium per year and the world's present measured resources of uranium (4.7 Mt - 5.5 Mt) are enough to last for some 70 – 80 years.
The plutonium from dismantled cold war nuclear weapon stockpiles is drying up and will end by 2013. The industry is trying to find and develop new uranium mines, mainly in Canada, Australia and Kazakhstan. However, those under development will fill only half the current gap.
spent fuel. Phosphates, seawater, uraniferous coal ash, and some type of oil shale
s are examples of unconventional resources being considered.
Worldwide, there were approximately 400 wet-process phosphoric acid plants in operation. Assuming an average recoverable content of 100 ppm of uranium, this scenario would result in a maximum theoretical annual output of 3700 tonnes U3O8. Historical operating costs for the uranium recovery from phosphoric acid range from $48–119/Kg U3O8. These operating costs are by far higher than uranium market prices, and most uranium recovery plants have been closed.
One method of extracting uranium from seawater is using a uranium-specific nonwoven fabric as an absorbent. The total amount of uranium recovered from three collection boxes containing 350 kg of fabric was >1 kg of yellow cake after 240 days of submersion in the ocean. According to the OECD, uranium may be extracted from seawater using this method for about $300/KgU The experiment by Seko et al. was repeated by Tamada et al. in 2006. They found that the cost varied from ¥15,000 to ¥88,000 (Yen) depending on assumptions and "The lowest cost attainable now is ¥25,000 with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses [sic]." With the May, 2008 exchange rate, this was about $240/Kg U
Among the other methods to recover uranium from sea water, two seem promising: algae bloom to concentrate uranium and nanomembrane filtering. Japan in 2009 proposes to use nearly 400 square miles (1,036 km²) of sponge farms to garner about 1300 tonnes of uranium yearly
So far, no more than a very small amount of uranium has been recovered from sea water in a laboratory.
shale was used for uranium
production in Sillamäe
, Estonia, and between 1950 and 1989 alum
shale was used in Sweden for the same purpose.
The European Commission said in 2001 that at the current level of uranium consumption, known uranium resources would last 42 years. When added to military and secondary sources, the resources could be stretched to 72 years. Yet this rate of usage assumes that nuclear power continues to provide only a fraction of the world’s energy supply. If electric capacity were increased six-fold, then the 72-year supply would last just 12 years.
The world's present measured resources of uranium, economically recoverable at a price of 130 USD/kg according to the industry groups OECD, NEA
and IAEA, are enough to last for 100 years at current consumption.
According to the Australian Uranium Association, yet another industry group, assuming the world's current rate of consumption at 66,500 tonnes of Uranium per year and the world's present measured resources of uranium (4.7 Mt) are enough to last for 70 years.
In his 1956 landmark paper, M. King Hubbert
wrote "There is promise, however, provided mankind can solve its international problems and not destroy itself with nuclear weapons, and provided world population (which is now expanding at such a rate as to double in less than a century) can somehow be brought under control, that we may at last have found an energy supply adequate for our needs for at least the next few centuries of the 'foreseeable future.'" Hubbert's study assumed that breeder reactor
s would replace light water reactor
s and that uranium would be bred into plutonium
(and possibly thorium
would be bred into uranium). He also assumed that economic means of reprocessing would be discovered. For political, economic and nuclear proliferation reasons, the plutonium economy did not materialize. Without it, uranium is used up in a once-through process and will peak and run out much sooner. However, at present, it is generally found to be cheaper to mine new uranium out of the ground than to use reprocessed uranium, and therefore the use of reprocessed uranium is limited to only a few nations.
The IAEA estimates that using only known reserves at the current rate of demand and assuming a once-through nuclear cycle that there is enough uranium for at least 100 years. However, if all primary known reserves, secondary reserves, undiscovered and unconventional sources of uranium are used, uranium will be depleted in 47,000 years.
The OECD estimates that with 2002 world nuclear electricity generating rates, with LWR, once-through fuel cycle, there are enough conventional resources to last 270 years. With breeders, this is extended to 8,500 years.
If one is willing to pay $300/KgU uranium, there is a vast quantity available in the ocean.
Deffeyes
estimates that if one can accept ore one tenth as rich then the supply of available uranium increased 300 times. His paper shows that uranium concentration in ores is log-normal distributed. There is relatively little high-grade uranium and a nearly inexhaustibly large supply of very low grade uranium.
Huber and Mills believe the energy supply is infinite and the problem is merely how we go about extracting the energy. Since the total amount of matter in the solar system is finite, this belief is clearly false. A more credible source with qualitatively similar conclusions is the following.
In 1983, physicist Bernard Cohen proposed that uranium is effectively inexhaustible, and could therefore be considered a renewable source of energy. He claims that fast breeder reactors
, fueled by naturally-replenished uranium extracted from seawater, could supply energy at least as long as the sun's expected remaining lifespan of five billion years. - whilst uranium is a finite resource mineral resource within the earth, the hydrogen in the sun is finite too - thus, if the resource of nuclear fuel can last over such time scales, as Cohen contends, then nuclear energy is every bit as sustainable as solar power or any other source of energy, in terms of sustainability over the finite realistic time scale of life surviving on this planet.
But the basic premise of reuse is open to question, said Ernest J. Moniz, a professor at the Massachusetts Institute of Technology
and a former deputy United States Secretary of Energy
.
He told the group that most of the thinking on reusing the fuel dated from decades ago, when uranium was thought to be scarce. But now, “roughly speaking, we’ve got uranium coming out of our ears, for a long, long time,” Professor Moniz said. Note that this statement does not give enough context to determine whether or not "a long, long time" means more than a generation or two.
Non-renewable resource
A non-renewable resource is a natural resource which cannot be produced, grown, generated, or used on a scale which can sustain its consumption rate, once depleted there is no more available for future needs. Also considered non-renewable are resources that are consumed much faster than nature...
. The availability of high-grade uranium ore will deplete over time meaning the fuel will become more environmentally and economically expensive to extract.
Limits to the impact of uranium depletion
Uranium is different from conventional energy resources, such as oil and coal, in several key aspects. Those differences limit the effects of short-term uranium shortages, but most have no bearing on the eventual depletion. Some key features are:- The uranium market is diverse, and no country has a monopoly influence on its prices.
- Even large increases in the price of uranium do not significantly affect the economics of nuclear power plants, because the cost of natural uranium makes up a very small fraction of the plant's operating costs (about 9%).
- Thanks to the extremely high energy density of uranium, stockpiling of several years' worth of fuel is feasible.
- Significant secondary supplies of already mined uranium exist, including decommissioned nuclear weapons, depleted uranium tails suitable for reenrichment, and existing stockpiles.
- Vast amounts of uranium, roughly 800 times the known reserves of mined uranium, are contained in extremely dilute concentrations in seawater.
- Introduction of fast neutron reactorFast neutron reactorA fast neutron reactor or simply a fast reactor is a category of nuclear reactor in which the fission chain reaction is sustained by fast neutrons...
s, combined with seawater uranium extraction, will make the uranium supply virtually inexhaustible. Fast reactors are already operating at the Beloyarsk Nuclear Power Plant in Russia and at the Monju Nuclear Power Plant in Japan.
Primary sources
About 96% of the global uranium reserves are found in these ten countries: AustraliaAustralia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...
, Uzbekistan
Uzbekistan
Uzbekistan , officially the Republic of Uzbekistan is a doubly landlocked country in Central Asia and one of the six independent Turkic states. It shares borders with Kazakhstan to the west and to the north, Kyrgyzstan and Tajikistan to the east, and Afghanistan and Turkmenistan to the south....
, USA, Niger
Niger
Niger , officially named the Republic of Niger, is a landlocked country in Western Africa, named after the Niger River. It borders Nigeria and Benin to the south, Burkina Faso and Mali to the west, Algeria and Libya to the north and Chad to the east...
, and Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
Out of those Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
(28% of world production) and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
(23%) are the major producers. In 1996, the world produced 39,000 tonnes of Uranium. And in 2005, the world produced a peak of 41,720 tonnes of uranium, although the production continues to not meet demand.
Various agencies have tried to estimate how long these primary resources will last, assuming a once-through cycle. The European Commission said in 2001 that at the current level of uranium consumption, known uranium resources would last 42 years. When added to military and secondary sources, the resources could be stretched to 72 years. Yet this rate of usage assumes that nuclear power continues to provide only a fraction of the world’s energy supply. If electric capacity were increased six-fold, then the 72-year supply would last just 12 years. The world's present measured resources of uranium, economically recoverable at a price of 130 USD/kg according to the industry groups Organisation for Economic Co-operation and Development
Organisation for Economic Co-operation and Development
The Organisation for Economic Co-operation and Development is an international economic organisation of 34 countries founded in 1961 to stimulate economic progress and world trade...
(OECD), Nuclear Energy Agency
Nuclear Energy Agency
The Nuclear Energy Agency is an intergovernmental multinational agency that is organized under the Organisation for Economic Co-operation and Development...
(NEA) and International Atomic Energy Agency
International Atomic Energy Agency
The International Atomic Energy Agency is an international organization that seeks to promote the peaceful use of nuclear energy, and to inhibit its use for any military purpose, including nuclear weapons. The IAEA was established as an autonomous organization on 29 July 1957...
(IAEA), are enough to last for "at least a century" at current consumption rates. According to the World Nuclear Association
World Nuclear Association
The World Nuclear Association , formerly the Uranium Institute, is an international organization that promotes nuclear power and supports the many companies that comprise the global nuclear industry...
, yet another industry group, assuming the world's current rate of consumption at 66,500 tonnes of Uranium per year and the world's present measured resources of uranium (4.7 Mt - 5.5 Mt) are enough to last for some 70 – 80 years.
Secondary resources
Only 62% of the requirements of power utilities are supplied by mines. The balance comes from inventories held by utilities and other fuel cycle companies, inventories held by governments, used reactor fuel that has been reprocessed, recycled materials from military nuclear programs and uranium in depleted uranium stockpiles.The plutonium from dismantled cold war nuclear weapon stockpiles is drying up and will end by 2013. The industry is trying to find and develop new uranium mines, mainly in Canada, Australia and Kazakhstan. However, those under development will fill only half the current gap.
Unconventional resources
Unconventional resources are occurrences that require novel technologies for their exploitation and/or use. Often unconventional resources occur in low-concentration. The exploitation of unconventional uranium requires additional research and development efforts for which there is no imminent economic need, given the large conventional resource base and the option of reprocessingNuclear reprocessing
Nuclear reprocessing technology was developed to chemically separate and recover fissionable plutonium from irradiated nuclear fuel. Reprocessing serves multiple purposes, whose relative importance has changed over time. Originally reprocessing was used solely to extract plutonium for producing...
spent fuel. Phosphates, seawater, uraniferous coal ash, and some type of oil shale
Oil shale
Oil shale, an organic-rich fine-grained sedimentary rock, contains significant amounts of kerogen from which liquid hydrocarbons called shale oil can be produced...
s are examples of unconventional resources being considered.
Phosphates
The soaring price of uranium may cause long-dormant operations to extract uranium from phosphate. The technology for recovering uranium from phosphate mines is mature.Worldwide, there were approximately 400 wet-process phosphoric acid plants in operation. Assuming an average recoverable content of 100 ppm of uranium, this scenario would result in a maximum theoretical annual output of 3700 tonnes U3O8. Historical operating costs for the uranium recovery from phosphoric acid range from $48–119/Kg U3O8. These operating costs are by far higher than uranium market prices, and most uranium recovery plants have been closed.
Seawater
The uranium concentration of seawater is approximately 3.3 parts per billion but the quantity of contained uranium is vast. Researchers estimate there are some 4.5 billion tonnes - this amounts to approximately 1000 times more than known terrestrial resources. Japan's approximately 56 nuclear reactors currently require roughly 8,000 tons of unprocessed uranium yearly.One method of extracting uranium from seawater is using a uranium-specific nonwoven fabric as an absorbent. The total amount of uranium recovered from three collection boxes containing 350 kg of fabric was >1 kg of yellow cake after 240 days of submersion in the ocean. According to the OECD, uranium may be extracted from seawater using this method for about $300/KgU The experiment by Seko et al. was repeated by Tamada et al. in 2006. They found that the cost varied from ¥15,000 to ¥88,000 (Yen) depending on assumptions and "The lowest cost attainable now is ¥25,000 with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses [sic]." With the May, 2008 exchange rate, this was about $240/Kg U
Among the other methods to recover uranium from sea water, two seem promising: algae bloom to concentrate uranium and nanomembrane filtering. Japan in 2009 proposes to use nearly 400 square miles (1,036 km²) of sponge farms to garner about 1300 tonnes of uranium yearly
So far, no more than a very small amount of uranium has been recovered from sea water in a laboratory.
Uraniferous coal ash
An international consortium has set out to explore the commercial extraction of uranium from uraniferous coal ash from coal power stations located in Yunnan province, China.Oil shales
Some oil shales contain uranium as a byproduct. Between 1946 and 1952, a marine type of DictyonemaBasidiolichen
Basidiolichens are lichenized members of the Basidiomycota, a much smaller group of lichens than the far more common ascolichens in the Ascomycota. In arctic, alpine, and temperate forests, the most common basidiolichens are in the agaric genus Lichenomphalia and the clavarioid genus Multiclavula...
shale was used for uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
production in Sillamäe
Sillamäe
Sillamäe is a town in Ida-Viru County in the northern part of Estonia, on the southern coast of the Gulf of Finland. It has a population of 16,183 and covers an area of 10.54 km²...
, Estonia, and between 1950 and 1989 alum
Alum
Alum is both a specific chemical compound and a class of chemical compounds. The specific compound is the hydrated potassium aluminium sulfate with the formula KAl2.12H2O. The wider class of compounds known as alums have the related empirical formula, AB2.12H2O.-Chemical properties:Alums are...
shale was used in Sweden for the same purpose.
Pessimistic uranium depletion outlook
Various agencies have tried to estimate how long these resources will last.- European Commission
The European Commission said in 2001 that at the current level of uranium consumption, known uranium resources would last 42 years. When added to military and secondary sources, the resources could be stretched to 72 years. Yet this rate of usage assumes that nuclear power continues to provide only a fraction of the world’s energy supply. If electric capacity were increased six-fold, then the 72-year supply would last just 12 years.
- OECD
The world's present measured resources of uranium, economically recoverable at a price of 130 USD/kg according to the industry groups OECD, NEA
Nuclear Energy Agency
The Nuclear Energy Agency is an intergovernmental multinational agency that is organized under the Organisation for Economic Co-operation and Development...
and IAEA, are enough to last for 100 years at current consumption.
- Australian Uranium Association
According to the Australian Uranium Association, yet another industry group, assuming the world's current rate of consumption at 66,500 tonnes of Uranium per year and the world's present measured resources of uranium (4.7 Mt) are enough to last for 70 years.
Optimistic uranium depletion outlook
All the following references claim that the supply is far more than demand. Therefore, they believe that uranium will not deplete in the foreseeable future.- M. King Hubbert
In his 1956 landmark paper, M. King Hubbert
M. King Hubbert
Marion King Hubbert was a geoscientist who worked at the Shell research lab in Houston, Texas. He made several important contributions to geology, geophysics, and petroleum geology, most notably the Hubbert curve and Hubbert peak theory , with important political ramifications. He was often...
wrote "There is promise, however, provided mankind can solve its international problems and not destroy itself with nuclear weapons, and provided world population (which is now expanding at such a rate as to double in less than a century) can somehow be brought under control, that we may at last have found an energy supply adequate for our needs for at least the next few centuries of the 'foreseeable future.'" Hubbert's study assumed that breeder reactor
Breeder reactor
A breeder reactor is a nuclear reactor capable of generating more fissile material than it consumes because its neutron economy is high enough to breed fissile from fertile material like uranium-238 or thorium-232. Breeders were at first considered superior because of their superior fuel economy...
s would replace light water reactor
Light water reactor
The light water reactor is a type of thermal reactor that uses normal water as its coolant and neutron moderator. Thermal reactors are the most common type of nuclear reactor, and light water reactors are the most common type of thermal reactor...
s and that uranium would be bred into plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
(and possibly thorium
Thorium
Thorium is a natural radioactive chemical element with the symbol Th and atomic number 90. It was discovered in 1828 and named after Thor, the Norse god of thunder....
would be bred into uranium). He also assumed that economic means of reprocessing would be discovered. For political, economic and nuclear proliferation reasons, the plutonium economy did not materialize. Without it, uranium is used up in a once-through process and will peak and run out much sooner. However, at present, it is generally found to be cheaper to mine new uranium out of the ground than to use reprocessed uranium, and therefore the use of reprocessed uranium is limited to only a few nations.
- IAEA
The IAEA estimates that using only known reserves at the current rate of demand and assuming a once-through nuclear cycle that there is enough uranium for at least 100 years. However, if all primary known reserves, secondary reserves, undiscovered and unconventional sources of uranium are used, uranium will be depleted in 47,000 years.
- OECD
The OECD estimates that with 2002 world nuclear electricity generating rates, with LWR, once-through fuel cycle, there are enough conventional resources to last 270 years. With breeders, this is extended to 8,500 years.
If one is willing to pay $300/KgU uranium, there is a vast quantity available in the ocean.
- Kenneth S. Deffeyes
Deffeyes
Kenneth S. Deffeyes
Kenneth S. Deffeyes is a geologist who worked with M. King Hubbert, the creator of the Hubbert peak theory, at the Shell Oil Company research laboratory in Houston, Texas. Deffeyes holds a B.S. in petroleum geology from the Colorado School of Mines and a Ph.D. in geology from Princeton University,...
estimates that if one can accept ore one tenth as rich then the supply of available uranium increased 300 times. His paper shows that uranium concentration in ores is log-normal distributed. There is relatively little high-grade uranium and a nearly inexhaustibly large supply of very low grade uranium.
- Huber and Mills
Huber and Mills believe the energy supply is infinite and the problem is merely how we go about extracting the energy. Since the total amount of matter in the solar system is finite, this belief is clearly false. A more credible source with qualitatively similar conclusions is the following.
- Bernard Cohen
In 1983, physicist Bernard Cohen proposed that uranium is effectively inexhaustible, and could therefore be considered a renewable source of energy. He claims that fast breeder reactors
Breeder reactor
A breeder reactor is a nuclear reactor capable of generating more fissile material than it consumes because its neutron economy is high enough to breed fissile from fertile material like uranium-238 or thorium-232. Breeders were at first considered superior because of their superior fuel economy...
, fueled by naturally-replenished uranium extracted from seawater, could supply energy at least as long as the sun's expected remaining lifespan of five billion years. - whilst uranium is a finite resource mineral resource within the earth, the hydrogen in the sun is finite too - thus, if the resource of nuclear fuel can last over such time scales, as Cohen contends, then nuclear energy is every bit as sustainable as solar power or any other source of energy, in terms of sustainability over the finite realistic time scale of life surviving on this planet.
- Ernest Moniz
But the basic premise of reuse is open to question, said Ernest J. Moniz, a professor at the Massachusetts Institute of Technology
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...
and a former deputy United States Secretary of Energy
United States Secretary of Energy
The United States Secretary of Energy is the head of the United States Department of Energy, a member of the President's Cabinet, and fifteenth in the presidential line of succession. The position was formed on October 1, 1977 with the creation of the Department of Energy when President Jimmy...
.
He told the group that most of the thinking on reusing the fuel dated from decades ago, when uranium was thought to be scarce. But now, “roughly speaking, we’ve got uranium coming out of our ears, for a long, long time,” Professor Moniz said. Note that this statement does not give enough context to determine whether or not "a long, long time" means more than a generation or two.