According to the Nuclear Energy Institute, as of November 2016, there were 450 nuclear power reactors operating in 30 countries, and 60 new plants were under construction in 15 countries. They provided about 11% of the world's electricity in 2012 (the latest year global data are available - Nuclear Energy Institute). Interestingly, 13 countries relied on on nuclear energy to supply at least 25% of their electricity in 2015. France (76.3%), The Ukraine (56.5%), Slovakia (55.9%), and Hungary (52.7%) all derive over 50% of their energy from nuclear sources.
To Read Now
Visit the World Nuclear Association and explore Nuclear Power in the World Today
Visit the Nuclear Energy Institute and explore Nuclear Units Under Construction Worldwide
Visit the U.S. Energy Information Administration and read about the U.S. Nuclear Industry
In the USA, there are currently 100 operable commercial nuclear reactors at 60 nuclear power plants. The newest reactor came online in June of 2016 (Watts Bar Unit 2 in Tennessee). Prior to that, the last new reactor to enter commercial service in the United States was in 1996. The Nuclear Regulatory Commission approved construction of four new reactors in 2012. These were the first permits approved in more than 30 years. (EIA, Energy Explained)
Since 1990, about 20% of our electricity has come from nuclear power generation, and this rate has stayed fairly steady.
Nuclear Fuel Supply
In Supply of Uranium, the World Nuclear Association describes the challenges and subjectivity of estimating uranium reserves. Following are some selected passages from this discussion.
Uranium is a relatively common element in the crust of the Earth (very much more in the mantle). It is a metal approximately as common as tin or zinc, and it is a constituent of most rocks and even of the sea...
An orebody is, by definition, an occurrence of mineralization from which the metal is economically recoverable. It is therefore relative to both costs of extraction and market prices. At present neither the oceans nor any granites are orebodies, but conceivably either could become so if prices were to rise sufficiently.
Measured resources of uranium, the amount known to be economically recoverable from orebodies, are thus also relative to costs and prices. They are also dependent on the intensity of past exploration effort, and are basically a statement about what is known rather than what is there in the Earth's crust...
Changes in costs or prices, or further exploration, may alter measured resource figures markedly. At ten times the current price, seawater might become a potential source of vast amounts of uranium. Thus, any predictions of the future availability of any mineral, including uranium, which are based on current cost and price data and current geological knowledge are likely to be extremely conservative.
The question of uranium supply clearly does not have a simple answer! One could say, that how much we "have" depends on how bad we want it--how much we are willing to pay. (This is true for estimating other types of reserves as well.)
The WNA then introduces the table below by saying, "With those major qualifications the following Table gives some idea of our present knowledge of uranium resources."
The Council on Foreign Relations, Global Uranium Supply and Demand (2010) adds more perspective to our understanding of uranium reserve estimates (FYI, "grade of uranium ore" is % of ore that is actually uranium)
Still, the overall amount of uranium is less important than the grade of uranium ore, according to a 2006 background paper by the German research organization Energy Watch Group. The less uranium in the ore, the higher the overall processing costs will be for the amount obtained. The group contends that worldwide rankings mean little, then, when one considers that only Canada has a significant amount of ore above 1 percent--up to about 20 percent of the country's total reserves. In Australia, on the other hand, some 90 percent of uranium has a grade of less than 0.06 percent. Much of Kazakhstan's ore is less than 0.1 percent.
Toni Johnson. (2010). Global Uranium Supply and Demand. Retrieved Sept February 2017.
The World Nuclear Association (December 2016) offers this conclusion about supply and demand--
Current usage is about 63,000 tU/yr. Thus the world's present measured resources of uranium (5.7 Mt) in the cost category less than three times present spot prices and used only in conventional reactors, are enough to last for about 90 years. This represents a higher level of assured resources than is normal for most minerals. Further exploration and higher prices will certainly, on the basis of present geological knowledge, yield further resources as present ones are used up.