Encyclopedia of Global Resources part 91 ppt

dominant role in the country’s natural gas industry. The leaders in exploration and production of natural gas are Statoil and Norsk Hydro, both government- owned firms. For the most part, international commercial companies that are involved in the Norwe- gian natural gasindustry work in partnership with the two state-owned companies. All companies working the offshore gas and oil fields must obtain licenses from the Norwegian government. The natural gas produced from the offshore deposits is of two different kinds: associated and nonassociated gas. Associated gas is gas that is dissolved in oil and is retrieved along with oil. It must be separated from the oil and cleaned before it is compressed for transport by pipeline. Nonassociated gas is contained in reservoirs that are gas dominated. When it reaches the surface from the wells, it needs only to be cleaned and compressed for transport. Most of the gas is immediately loaded onto tankers and transported to re- fineries; however, some is transported by pipeline to two terminalsnear Bergen. Fromthere, it isprocessed and sent to the European Union and other countries of Western Europe. A small amount of the gas is pro- cessed offshore and is exported to the United King- dom and the Netherlands. Domestic consumption of natural gas is limited. The country ranks fifty-fifth globally in consumption of the resource. Domestically,Norway usesnatural gas only for generatingpower offshore and forproducing methanol and processing gas on land. Globally, Nor- way is an important provider of natural gas, especially to the European Union,forwhich it isthe second largest supplier. Hydropower Hydropower has been an important source of energy in Norway since the early nineteenth century. Nor- way’s hydropower comes from its vast number of waterfalls and, as an industry, has allowed Norway to become an industrialized nation. In the early twentieth century (1910 to 1925), the first major expansion of the Norwegian hydropower industry occurred. The development of hydropower and the building of hydropower plants increased immensely after World War II, especially from 1960 to 1985, and has continued to expand. Hydropower uses water to produce energy. It pro- vides a clean, renewable source of energy. It does not produce greenhouse gases.However, the exploitation of waterfalls and the modification of river flow, cou - pled with water storage by use of reservoirs and dams, impact the environment and result in some environmental problems. This is especially true in terms of fish and biodiversity. Norway is addressing these issues and working to maintain a strong hydropower industry while protecting its waterfalls, rivers, and eco- systems. Hydropower in Norway is almost 99 percent under government control; the state, counties, and municipalities own the majority of the hydropower plants. No development of water resources may be un- dertaken withoutauthorization bythe central government. Those operations that are privately owned are state licensed, and at the end of the license duration, they are placed under public control. Norway is thesixthlargest producer ofhydropower in the world.It is ableto meet almostallof its domestic electricity and energy needs throughthe useof hydropower. Its aluminum, electrochemical, and electro- metallurgical industries depend on hydropower as their major energy source. Norway ranked twenty- seventh in the world in the production of electricity and twenty-sixth in its consumption in 2007. Norway participates in powertrade with its neighboring countries under the direction of Nordel and Nad Pol. The power tradeis accomplishedby the use of cables. Nor- way is extremely important to Europe as a source of hydropower because almost 50 percent of Europe’s hydropower storage capacity is in Norway. Not only does Norway export electric power, but the country also is instrumental in assisting other countries in the development of hydropower through sharing its vast knowledge of hydropower development and uses. Forests With 37 percent of its land in forest, Norway has an important forest industry. The country’s forests provide a variety of products, including logs, sawed lum- ber, paper, and pulp. Norwegian forests cover 119,000 square kilometers. Twenty-threepercentof its forestis used for the production of timber and forest products. Unlike the hydropower, oil, and gas industries, Norway’s forests are primarily under private owner- ship. Throughout its history, Norway has carefully managed its forests by policies of protection and re- generation. These practices have resulted in an annual increase in biomass each year. One of the most important techniques in forest management used by Norway is that of cutting fewer trees each year than the annual increase in trees will permit. These prac - tices have given Norway a healthy, large forest that 828 • Norway Global Resources annually produces a high yield of timber. An added benefit for the country has been the reduction of greenhouse gases. Norway has developed a national parks project that raised the amount of protected forest in the country to 15 percent by 2010. Much of the felled timber which goes to sawmills and becomes sawed timber is used within the country. Wood is the major material used in construction in Norway, particularly in the construction of residen- tial buildings. Although Norway relies heavily on hydropower for energy, firewood remains a significant source of energy for heating private homes. Norwe- gian wood and forest products are also important in the global market. Norway exports a considerable amount of roundwood and forest products, which account for approximately 11 percent of the country’s export value. Paper and pulp products dominate the Norwegian trade in forest products. Norway exports approximately 1 million metric tons of newsprint each year. Western Europe is the primary market for newsprint as well as higher grades of paper important in the book-publishingindustry. Other exported Nor- wegian wood-derived products include packing paper, pulp made from ground wood fiber, and pulp produced by boiling the wood in a chemical solution. Norway’s forest industry contributes slightly less to the economy thanthefishing industry does,butit out- performs the aluminumindustryas a source of export revenue. Fisheries Fisheries always have been an important segment of the Norwegian economy. Worldwide, the fishing industry has experienced a decline in fish and shellfish populations, a decline in the number of different species, and a change in location of certain species because of climate change, pollution, and exploitive overfishing. Norway’s coastal waters in the North Sea, the Norwegian Sea, and the Barents Sea provide evi- dence of this decline; Norway is implementing policies and laws to combat this problem and to preserve its valuable resource of fish and shellfish. In response to a continuing decline in the stock of coastal cod, which began in 1994 and continued steadily through 2004, Norway enacted restrictions on the commercial fishing industry’s ability to take these fish. The restrictions, with certain modifications, were kept in place through 2008 and were planned to continue through 2009. The policy has had positive effects: The stock of coastal cod in the Barents Sea increased such that, although quotas were still in effect on these fish, the number that could be caught was increased. Norway also participates indiscussions and effortswith the Eu- ropean Union to establish a bilateral fisheries agree- ment to reduce the amount of fish caught and dis- carded by fishing companies fishing for specific types of fish. In addition to placing controls on fishingin coastal waters, Norway has developed and promoted aquaculture, a process that involves farm raising of fish. The government funds 29 percent of the cost of research and development of aquaculture. In 2009, the Norwegian government established sixty-five new licenses for the farming of salmon, trout, and rainbow trout. Five of these licenses are restricted to firms prac- ticing organic aquaculture. The two major species raised in aquaculture are Atlantic salmon and rainbow trout; however, Norway has planned to expand the aquaculture industry. Aquaculture accounts for almost 50 percent of thevalueof Norway’s fish exports. Norway ranks eleventh in theworld in the catching and farming of fish. Seafood products constitute more than 4 percent of Norwegian exports. Norway is the second largest global exporter of fish. In 2007, the main export markets for Norwegian seafood were France, Russia, Denmark, and Great Britain. Norway exports a large variety of fish and shellfish, including herring, mackerel, haddock, cod, and prawns. Major markets for the various species vary considerably, with Japan as the major mackerel export market, Russia as the major herring export market, Portugal as the major cod export market, and Sweden as the major prawn export market in 2007. Other Resources Norway is not significantly rich in minerals but does have deposits of iron ore, copper, lead, zinc, titanium, pyrites, nickel, olivine, and carbonate. Deposits of olivine are particularly good in the region of Åheim. Ol- ivine has a number of important industrial uses: as a slag conditioner in pig-iron production, in abrasives, and in the making of exterior covers of subsea pipe- lines. Norway also has several important deposits of marble and limestone in Verdal. Norway is an important supplier of both carbonate slurry and liquid marble slurry to the paper manufacturing industry. Both slurriesareused inthe coating of paper. There are significant deposits of zinc and copper in the provinces of Trondheim and Røros. Shawncey Webb Global Resources Norway • 829 Further Reading Fagerberg, Jan, David Mowery, and Bart Verspagen, eds. Innovation, Path Dependency and Policy: The Nor- wegian Case. New York: Oxford University Press, 2009. Field, Barry C. Natural Resource Economics: An Introduc- tion. 2d ed. Boston: Irwin/McGraw-Hill, 2001. Førsund, Finn R. Hydropower Economics. New York: Springer, 2007. Hannesson, Rögnvaldur. Petroleum Economics: Issues and Strategies of Oil and Gas Production. Westport, Conn.: Quorum, 1998. Hansen, Stein, Pål Føyn Jesperson, and Ingeborg Ras- mussen. Towards a Sustainable Economy: The Applica- tion of Ecological Premises into Long-Term Planning in Norway. New York: Palgrave Macmillan, 2001. See also: Fisheries; Forestry; Forests; Hydroenergy; Oil and natural gas reservoirs. Nuclear energy Category: Energy resources Nuclear power, an outgrowth of the development of the atomic bomb during World War II, once seemed to hold the promise of abundant, clean energy. However, it became controversial, and few new plants were constructed in the late twentieth century. Nonetheless, nuclear power is being revisited as a possible remedy for global warming becauseof its low greenhouse-gasemis- sions. Background The fission reaction that occurs in a nuclear reactor releases tremendous amounts of energy in the form of heat. This heat can be used to produce steam, and the steam can be used to drive an electric generator. It appears that uranium, the fuel for nuclear reactors, will far outlast oil and coal as a source of energy. How- ever, concerns about the safety of nuclear reactors and about the disposal of used fuel and other wastes have slowed thepaceof reactor developmentdramati- cally. In addition, nuclear power plants are usually more expensive to construct than coal- or gas-fired plants. Scientific Principles and Historical Background Naturally occurring uranium consists of 99.3 percent uranium 238 and 0.7 percent uranium 235. The nuclei of both of these isotopes contain 92 protons. Uranium-238 nuclei also contain 146 neutrons, while uranium-235 nuclei contain 143 neutrons. When a neutron strikes the nucleus of a uranium-235 atom, the nucleus splits roughly in half. Several neutrons and considerable heat are released. This process is called fission. The neutrons that are released can cause the fission of other uranium-235 nuclei, so the process continues in a chain reaction. Thesmaller nuclei that result from fission are calledfission products. They are highly radioactive, and this radioactivity is accompanied by significant heat generation. When 1 gram of uranium fissions, it releases the same amount of heat as burningabout 3 metric tons of coal or more than 12 barrels of oil. In 1934, Enrico Fermi, working in Rome, was bombarding uranium atoms with neutrons. He expected the neutrons to be absorbed and new, heavier atoms to result. However, the chemical properties of the atoms he produced were not what he expected. Lise Meitner, Irène Joliot-Curie (the daughter of Nobel Prize winner Marie Curie), and Otto Hahn repro- duced Fermi’s experiments. They too were baffled by the results. Finally, Hahn realized what was happen- ing: Instead of being absorbed into the uranium-235 nucleus, the neutrons were causing that nucleus to split roughly in half. The result was two lighter atoms rather than one heavier one. Because these researchers were working with very small quantities of uranium, they did not produce a chain reaction and did not detect the heat being released. In 1939, William Laurence, a science reporter for The New York Times, asked Fermi and Niels Bohr, another famous physicist, whether a small quantity of uranium 235 could be used as a bomb as powerful as several thousand metric tons of trinitrotoluene (TNT). Fermi simply said, “We must not jump to hasty conclusions,” but apparently Fermi and Bohr had already considered this possibility. On May 5, 1940, The New York Times carried a front-page story by Laurence under the headline “Vast Power Source in Atomic En- ergy Opened by Science.” Fermi apparently approached the U.S. Navy with his information, but it was not interested. Finally, in 1941, Albert Einstein signed a letter informing Presi - dent Franklin Roosevelt of the possibilities of nuclear 830 • Nuclear energy Global Resources power, and thegovernment finallytooknotice. Under Fermi’s direction, the first nuclear reactor was built in an abandoned squash court under Stagg Field at the University of Chicago. This reactor consisted of tubes of naturally occurring uranium embedded in large blocks of graphite. On December 2, 1942, this reactor “went critical” for the first time. A reactor is said to be “critical” whenthe numberof fissions in one second is the same as the number in each second that follows. Fermi’s reactor used naturally occurring uranium. However, bombs could not be built that way. There were two possible ways to build an atomic bomb: Either the uranium 235 could be separated from the uranium 238, or uranium 238 could be bom- barded with neutrons and transformed into plutonium 239. Both uranium 235 and plutonium 239 fission easily when struck by neutrons. In these early days, separating uranium 235 from uranium 238 was very difficult, but it could be done. Transforming uranium 238 into plutonium 239 appeared to be the easier route. Large plutonium production reactors were build along the Columbia River near Richland, Wash- ington, and by 1945, enough plutonium had been produced to build the bomb that destroyed Nagasaki, Japan. Ultimately, the separation of the two types of uranium proved to be somewhat easier than expected; the bomb dropped on Hiroshima, Japan, was built of uranium 235. During the operation of the plutonium production reactors, that fact that large amounts of heatwere produced by the fission reaction became obvious, and people began to think of ways to use thisheat. Thisled to the idea of using reactors togenerate steam to drive electric generators. Nuclear Reactor Design The electric generators and the steam turbines at a nuclear plant are similar to those at a coal-,oil-, or natural gas-fired plants. The difference lies in how the steam that drives the turbine is produced. Nuclear reactor fuel consistsof uranium orplutonium oxidepel- lets contained inside zirconium tubes called fuel rods. These rods are arranged in a grid pattern, with space between them for coolant to flow. This part of a nuclear reactor is called the core. Movable control rods of neutron-absorbing material such as cadmium are used to regulate the fission rate in the reactor. The reactor core is housed in a strong steel container called the pressure vessel. Coolant flows into the pressure vessel, from which it flows through the core and ab - sorbs the heat produced by fission. Then the heated coolant flows out of the pressure vessel and into other parts of the system. This heat is used to make steam. The cooling fluid can be a gas such as air or carbon dioxide, a liquid such as water, or a molten metal such as sodium. Nearly all electric power reactors in the United States are water cooled. There are two basic designs: pressurized-water reactors and boiling-water reactors. In a pressurized-water reactor, water at very high pressure passes through the reactor core, the place where the uranium fuel is located. This water, which is called the primary water, absorbs the heat released by fission but does not boil because it is under such high pressure. After this very hot water leaves the reactor, it passes through aheat exchanger calleda steam generator. In the steam generator, heat is transferred from the primary water to water at lower pressure. This lower-pressure water, which is called secondary water, boils as it absorbs heat from the primary water. The steam produced when the secondary water boils is used to spin the turbines that drive the electric generators, while the primary water returns to the reactor to pick up more heat. Both the reactor and the steam generator are housed inside a large, strong concrete structure called a containment building. The primary water, which becomes radioactive as it passes through the reactor core, never leaves the containment building; the secondary water, which does leave the containment building, is not radioactive. In 1987, there were sixty-nine operating nuclear power plants with pressurized-water reactors in the United States. In a boiling-water reactor, about 10 percent of the water passing through the core is turned directly into steam. This steam leaves the reactor and goes directly to the turbines. No steam generator is required in this system, because steam is generated directly in the reactor. Because steam absorbs heat more slowly than Global Resources Nuclear energy • 831 Types of Nuclear Reactors in Development • Gas-cooled fast reactors • Lead-cooled fast reactors • Molten salt reactors • Sodium-cooled fast reactors • Supercritical water-cooled reactors • Very high temperature gas reactors liquid water, care must be taken to avoid the forma - tion of too much steam in the reactor. This could lead to overheating of the uranium and damage to the core. As a result, a boiling-water reactor generates less power than a pressurized water reactor of the same core size. Many of the problems with pressurized- water reactor plants have been caused by the steam generators. Because boiling-water reactors do not have separate steam generators, these problems are eliminated. On the other hand, the steam from a boiling- water reactor ismildly radioactive,so theturbines and other equipment must be treated as radioactive material. This is not the case with a pressurized-water reactor. In 1987, there were thirty-eight power stations using boiling-water reactors in the United States. Gas-cooled reactors have not been used much in the United States, but Great Britain has used them extensively. Commonly, carbon dioxide under high pressure is passed through the reactor core. Leaving the core, the carbon dioxide passes through a steam generator, where it heats and boils water to produce steam. This steam is used to drive the turbines. In a sense a gas-cooled reactor is similar to a pressurized- water reactor; however, thesteamgenerators are quite different because the primary fluid is a gas rather than a liquid. Some reactors are cooled by molten metals such as sodium. Because sodium melts at about 98° Celsius, it is a liquid at the temperatures found in a reactor system. Sodium conducts heat better than water does, so a sodium-cooledreactor can generate heat at a higher rate than a water-cooled one. On the other hand, sodium becomes highly radioactive as it passes through the reactor core, while water becomes only mildly radioactive. Also, sodium reacts violently with water, so great care must be taken to prevent leaks between the sodium reactor coolant and the steam being produced in the steam generator. Typical sodium-cooled reactors have three coolant loops. The primary sodium that flows through the reactor core transfers its heat to a secondary sodium loop in an intermediate heat exchanger.All this takes place insidethe containment building. The secondary sodium flows to a steam generator that is outside the containment building. Here steam is produced to drive the turbines. Molten metal-cooled reactors are also calledfast re- 832 • Nuclear energy Global Resources The San Onofre Nuclear Power Plant is located in San Diego County, California. (AFP/Getty Images) actors, a name which refers to the fact that the neu - trons, which emerge from fission at very high speed, are not slowed down before they cause another fission. In water-cooled reactors theneutrons are slowed down a great deal; these reactors are called thermal reactors. Although fast reactors are potentially more efficient and economical than thermal reactors, thermal reactors appear to be safer. As a result, thermal reactors currently dominate the electric power generation business. Another advantage of a fast reactor is that it can act as a breeder reactor. In a breeder reactor, some of the neutrons produced by fission go on to produce other fissions, but some of the neutrons react with uranium 238 and transform it into plutonium 239. Plutonium can be used to build bombs, but it can also be used in place of uranium 235 as reactor fuel. It is actually possible in a breeder reactor for the amount of plutonium produced to exceed the amount of uranium consumed. Therefore, the nuclear industry is not limited to using the 0.3 percent of natural uranium that is uranium 235; it can also use the uranium 238 after converting it into plutonium. Many fast reactors are research reactors, but some countries have also used them for electric power generation. France hasoperated a fast breederreactorfor power generation, as have Russia and Kazakhstan. The Kazakhstan reactor was also used for water desalination. Russia is developing a small fast breeder reactor based on a submarine design that can use a variety of cooling agents, such as lead and bismuth, to be used to deliver electric power for remote areas. The reactors described above are often labeled Generation I and II reactors. More advanced Genera- tion III reactors are in operation in Japan and are under construction elsewhere. Third-generation reactors are more standardized than earlier reactors, speeding up the permitting process, and have longer operating lives, usually sixty years. They are also safer, with re- duced possibility of core melt accidents. These reactors also are able to “burn” their fuel at a higher rate, reducing the waste. Many of the Generation III reactors in the planning and construction stages are light-water reactors, such as those under construction in South Korea and in Olkiluoto, Finland. The Olkiluoto reactor is often seen as a useful design and has been considered for adoption for some new U.S. reactors. Canada is developing two heavy-water de - signs based on the earlier CANDU-6 reactors. High- temperature gas-cooled reactors are also under con - struction, most of which use helium as a coolant. The Pebble Bed Modular Reactor, being developed in South Africa, also uses helium. Liquid-metal-cooled fast breeder reactors have been in operation since the 1950’s, and several new designs are under development in Japan, Russia, and Italy. Generation IV reactors are being developed by a consortium ofseveral countries,including the United States, and are expected to be constructed by the late 2020’s. Six different types of Generation IV reactors are under consideration; four are fast neutron reactors. The developmental process for Generation IV reactors got under way in 2002, when ten countries joined togetherto consider the development of six reactor types. These designs are still experimental and not all may be built, but they offer some intriguing possibilities. Most of these reactors use uranium as fuel, although the lead-cooled fast reactors make use of de- pleted weapons-grade uranium and plutonium or thorium as fuel. The United States and the former So- viet Union began dismantling nuclear weapons in 1987. The weapons-grade plutonium is blended with uranium oxide into mixed oxide fuel that is suitable for use in power reactors. This approach has the advantage of decreasing the numberof nuclear weapons as well as increasing the supply of fuel for power reactors. This mixedoxide fuel isused in GenerationIand II reactors, but it may also be used to fuel more advanced reactors. Thoriumhas been consideredas fuel for some of these new types of reactors, in part because it is far more common than uranium. India in particular has made the development of thorium as a fuel a major objective of its nuclear-power program. The fabrication costsfor thorium fueldo not makeit a feasible alternative to uranium, but this may change if the cost of uranium increases substantially. Fusion Fusion is an entirely different process from fission. Fission is the splitting apart of the nucleus of a uranium or plutonium atom. Fusion is the joining of two light atoms to form a heavier one. For instance, two hydrogen atoms can fuse to form a helium atom. The fusion reaction is also accompanied by the release of large amounts of heat. In fact it is the fusion reaction that generates the tremendous heat that stars give off. The potential of fusion to drive nuclear reactors is be - ing explored, but there are significant problems in - volved. Global Resources Nuclear energy • 833 An ordinary hydrogen atom has a nucleus com - posed of a lone proton, but there are two other forms of hydrogen. Different forms of the same element are called isotopes, and the isotopes of hydrogen are called deuterium and tritium. A deuterium nucleus contains a proton and a neutron, while a tritium nucleus contains a proton and two neutrons. Deuterium occurs naturally. Some of the hydrogenatoms innatu- ral water molecules are actually deuterium. The deuterium in a cup of coffee could produce enough energy through fusion to drive a car for about a week of normal driving. Fusion, like fission,was first usedin weapons ofwar. In a hydrogen bomb one deuterium nucleus and one tritium nucleus fuse to make a helium nucleus, which is composed of two protons and two neutrons, plus a free neutron. Unlikedeuterium, tritiumis radioactive and does not occur in nature. It is commonly made in fission reactors by bombarding lithium atoms with neutrons. The deuterium-tritium reaction is one of the most promising for power-producing fusion reactors. The most difficult aspect of fusion is that the fuel atoms must be heated to temperatures in the range of 100 million degrees Celsius in order to make the reaction occur at all. In 1989, there were newspaper re- ports of “cold” fusion—that is, fusion occurring at or near room temperature. However, these claims have not stoodup undercloser inspection.Although scientists have been able to produce the extremely high temperatures required for fusion, they havebeen able to maintain them only for very short times. The biggest problem concerns how to contain the fuel at these temperatures. Certainly no material known could remain a solid at these temperatures. In- stead, researchers have explored the use of magnetic fields or powerful laser light pulses to contain the fusion fuel. The magnetic confinement method uses a doughnut-shaped vacuum chamber with a very in- tense magnetic field inside it. The fuel is heated by passing an electric current through it until the required temperature is reached. Experimental fusion reactors that use magnetic containment are called tokamak reactors. The Tokamak Fusion Test Reactor at Princeton University in New Jersey is an example of this type. Laser containment involves placing the fusion fuel in a pellet and illuminating the pellet with extremely powerful laser light. Details of pellet construction are highly classified. It is known that the laser light com - presses the inner layers of the pellet while burning off the outer layers. As the inner layers are compressed, they heat up, and fusion begins. Each pellet reacts for only a smallfractionof a second,so it is notclear how a sustained fusion reaction could be maintained in this way. The NOVA laser fusion facility at the Lawrence Livermore National Laboratory uses the laser containment approach. Fusion remained in the experimental stages in the first decade of the twenty-first century. In the 1950’s, researchers predicted that commercial fusion reactors were twenty years away. In the mid-1990’s, commercial exploitation still seemed to be about twenty years away. Some experts believe that commercial fusion will not be achieved in the foreseeable future. The attraction of fusion is that its products are not radioactive. If fusion can be harnessed for the generation of electricity, the significant waste-disposal problems posed by fission can be eliminated. The United States, Japan, South Korea, Russia, China, In- dia, and the European Union are part of the Interna- tional Thermonuclear Experimental Reactor project directed toward buildinga workable fusionreactor. In 2005, the organization agreed to a site at Cadarache in southern France as the location for a reactor to demonstrate the feasibility of fusion. Even when completed, this reactor is unlikely to generate enough energy gain for use as a power plant. Thus, fusion power remainsa long-termsolutionfor world energyneeds. Reactor Safety and Nuclear Waste One of the major factors limiting the development of nuclear power is concern about reactor safety. On March 28, 1979, there was a major accident in reactor number 2 at the Three Mile Island facility nearHarris- burg, Pennsylvania. The accident began when one of the turbinesstopped because of a minor malfunction. Although the fission reaction was stopped by the in- sertion of control rods very early in the accident, the uranium fuel continued to generate considerable heat because of the radioactive decay of the atoms produced when the uranium nuclei split. Water must continue to flow over the fuel rods long after fission stops in order to remove this heat.Through a series of errors by operating personnel at Three Mile Island, this flow of water was not maintained, and later, part of the core was not even submerged in water. As a result, much of the core overheated and melted. Al - though a coremeltdown is aserious event, inthis case, the exposure of people outside the reactor complex 834 • Nuclear energy Global Resources to radioactivity was negligible. Despite widespread concern over the Three Mile Island accident, one could argue that it demonstrated that pressurized- water reactors are actually quite safe. Such was not the public perception, however, and there were no new commercial reactor contracts signed in the United States between 1979 and 1996. On April 26, 1986, a much more serious reactor accident occurred at the Chernobyl nuclear power sta- tion in Ukraine (at thetime part of the Soviet Union). As a result of serious errors by operating personnel, the reactor went out of control. More and more fissions occurred every second, and the water could not carry away all the heat. Steam pressure built up until the reactor burst, and much radioactive material was expelled into the atmosphere. This radioactive material wasdetected asfar away as Sweden. About 135,000 people were evacuatedfrom the area around thereac- tor. Two people died immediately as a result of the bursting of the reactor. Another twenty-nine died of acute radiation poisoning within a short time. Esti- mates indicated that cancer deaths worldwide would increase by seventeen thousand over the fiftyyears following this accidentas a resultof the radioactive material released intothe atmosphere; scientists havesince revised this figure downward. The design of the Cher- nobyl reactor is very different from the pressurized- and boiling-water reactors used in the United States and most other countries. This accident seems to demonstrate that the type of reactor used at Cher- nobyl is not safe enough. In the United States, several government-owned reactors of a similar design were permanently shut down afterthe Chernobylaccident. These were plutonium production reactors rather than commercial electric powergenerationreactors. Reactor safety isan importantand a complicated issue that is difficult for nontechnical people to under- stand. Undeniably, nuclear reactors involvesome risk, but so do other forms of power generation. Deciding what level of risk is acceptable is a difficult issue. Many people envision a reactor accident with large loss of life and conclude that the risk is unacceptable. Such an accident has not occurred with the types of reactors in use in the United States, but it cannot be com- pletely ruled out. The third- and fourth-generation reactors under development are safer than present reactors, so that accidents such as Three Mile Island or Chernobyl are highly unlikely. Because the new nuclei that form during fission are highly radioactive, the spent fuel that is periodically removed from the reactor must be handled with great care. The radioactivity is accompanied by considerable heat generation, and provisions must be made to remove this heat from the used fuel. It takes thousands of years for the radioactivity to diminish to safe levels, so usedfuel must be stored in places that are expected to remain unaffected by earthquakes, hurri- canes, and othernaturaldisasters for a verylong time. Reactor plants are required to provide storage facilities for their own used fuel, but this is not a permanent solution. Although several national governments have been making plans for permanent, long-term storage of used fuel and other nuclear waste materi- als, technical and political problems have delayed the opening ofsuch facilities.In addition to the used fuel, radioactive waste is created during the mining, refin- ing, and processing ofreactorfuel as wellas from reactor operation. Although this waste is generally less hazardous than used fuel, provisions must be made for disposing of it safely. The United States has opened the Waste Isolation Pilot Plant near Carlsbad, New Mexico, to deal with certain types of these wastes. The United States has been building an underground disposal site for high-level radioactive wastes at Yucca Mountain, Nevada. However, in 2009, the Obama administration put the project on hold pending further safety analysis. Reactors have a useful life of about forty years. Once a reactor is retired, provisions must be made to seal it permanently because many parts of the reactor will remain radioactive for a long time. The Revival of Nuclear Energy By the earlytwenty-first century,concerns withcarbon dioxide emissions from coal- and oil-fired power plants and increasing energy demand had led many people to advocate theuse of nuclearpower. When thecost of carbon emissions from coal- or gas-fired power plants are taken into account, nuclear power becomes more cost-effective than before. Several nations are planning or building nuclear power plants, with some scheduled to be operational in the second decade of the twenty-first century. Even some Scandinavian countries that had turned against nuclear energy are returning to consideration of its use. All told, as of 2009, some forty reactors were under construction in eleven countries, with another one hundred planned to be operational by 2020; more than two hundred others were under consideration. Many of these reac - tors in the planning stagesare in Asia.India, forexam - Global Resources Nuclear energy • 835 ple, had six reactors under construction that were expected to be completed by 2010, one of which is a prototype breeder reactor. China has eleven operating reactors and intends to quadruple its capacity by 2020. In 2009, the U.S. government agreed to provide up to $122 billion in loan guarantees for building twenty-one new reactors. The first stage of this project is projected to add seven reactors by 2015 or 2016 at a cost ranging between $5 and $12 billion. Increasing costs for oil and coal, coupled with environmental concerns, have helped to drive a return to nuclear power. In some cases, the fuel costs for a nuclear power plant are one-third those of a coal-fired plant and one-quarter of a gas-fired plant. The typi- cally long construction periods for nuclear power plants and the issue of nuclear waste disposal continue to keep overall costs high, however, especially in the United States and Western Europe. The continuing development of new types of reactors, sometimes labeled Generation IV reactors, should lead to more efficient operation of nuclear power plants, making nuclear electric powerafeasible option in thefuture. Research on and development of nuclear energy has been directed primarily toward electric power generation. By the late twentieth century, other uses were being developed. Desalination requires large amounts of energy, and some countries, such as Kazakhstan, have already made use of nuclear energy in this area. Electric power generation will remain the primary focus of nuclear energy in the future, but other uses are also being considered. Edwin G. Wiggins, updated by John M. Theilmann Further Reading Bodansky, David. Nuclear Energy: Principles, Practices, and Prospects. 2d ed. New York: Springer, 2004. Caldicott, Helen. Nuclear Power Is Not the Answer. New York: New Press, 2006. Eerkens, Jeff W. The Nuclear Imperative: A Critical Look at the Approaching Energy Crisis. Dordrecht, the Neth- erlands: Springer, 2006. Grimston, Malcolm C., and Peter Beck. Double or Quits? The Global Future of Civil Nuclear Energy. Lon- don: Earthscan, 2002. Heppenheimer, T. A. The Man-Made Sun: The Quest for Fusion Power. Boston: Little, Brown, 1984. Herbst, Alan M., and George W. Hopley. Nuclear En- ergy Now: Why the Time Has Come for the World’s Most Misunderstood Energy Source. New York: John Wiley, 2007. Hewitt, G. F., and John G. Collier. Introduction to Nu - clear Power.2ded. New York:Taylor &Francis,2000. Hodgson, Peter E. Nuclear Power, Energy, and the Envi- ronment. London: Imperial College Press, 1999. Lake, James A., Ralph G. Bennett, and John F. Kotek. “Next Generation Nuclear Power.” In Oil and the Future of Energy. Guilford,Conn.:Lyons Press, 2007. Morris, Robert C. The Environmental Case for Nuclear Power: Economic,Medical, and Political Considerations. St. Paul, Minn.: Paragon House, 2000. Murray, Raymond LeRoy. Nuclear Energy: An Introduc- tion to the Concepts, Systems, and Applications of Nu- clear Processes. 6th ed. Boston: Butterworth-Heine- mann, 2009. Novick, Sheldon M. The Careless Atom. Boston: Hough- ton Mifflin, 1969. Nuttall, William J.Nuclear Renaissance: Technologies and Policies for the Future of Nuclear Power. New York: Tay- lor and Francis, 2005. Suppes, J., and TrumanS. Storvick. Sustainable Nuclear Power. Boston: Elsevier/Academic Press, 2007. Tucker, William. Terrestrial Energy: How Nuclear Power Will Lead the Green Revolution and End America’s En- ergy Odyssey. Savage, Md.: Bartleby Press, 2008. Wolfson, Richard. Nuclear Choices: A Citizen’s Guide to Nuclear Technology. Rev. ed. Cambridge, Mass.: MIT Press, 1993. Web Sites U.S. Department of Energy Nuclear Energy http://www.energy.gov/energysources/nuclear.htm World Nuclear Association http://www.world-nuclear.org See also: Electrical power; Fermi, Enrico; Manhattan Project; Nuclear Regulatory Commission; Nuclear waste and its disposal; Plutonium; Steam and steam turbines; Uranium. Nuclear Energy Institute Category: Organizations, agencies, and programs Date: Established 1994 The Nuclear Energy Institute, based in Washington, D.C., is the nuclear industry’s private, nonprofittrade 836 • Nuclear Energy Institute Global Resources association, representing about three hundred compa - nies and organizations worldwide. It is an advocate for the nuclear energy industry regarding public information, legislation,and the implementation of regulatory policies and procedures. Background In March of1994, thefunctions previously performed by four nuclear energy industry organizations were incorporated intoa single organization called the Nu- clear Energy Institute (NEI). The first of the four organizations was the American Nuclear Energy Coun- cil, whichwas responsible for governmentaffairs. The second organization was the Nuclear Management and Resources Council, which managed regulatory and technical issues. Third was the U.S. Council for Energy Awareness, which maintained a national nuclear energy communications program. The fourth organization, the Edison Electric Institute, continues to exist, although its nuclear activities and programs in nuclear waste and nuclear fuel supply became the domain of the NEI. Impact on Resource Use The NEI promotes the use of nuclear energy and supports the nuclear energy industry. The institute’s stated purpose is “to foster and encourage the safeuse and development of nuclear energy.” The types of companies and organizations belonging to the NEI include utilities that own and operate nuclear power plants, nuclear plant equipment suppliers, construction and engineering firms, nuclear fuel cycle companies, producers of radionuclides and radiopharma- ceuticals, law firms, consulting firms, and labor unions. Dion C. Stewart Web Site Nuclear Energy Institute http://www.nei.org/ See also: Atomic Energy Commission; Nuclear energy; Nuclear waste and its disposal. Nuclear Regulatory Commission Category: Organizations, agencies, and programs Date: Established 1975 The Nuclear Regulatory Commission is the indepen - dent U.S. government agency that regulates civilian use of nuclear technology. Its most important duty is the regulation of nuclear power plants and fuels. Background The Nuclear Regulatory Commission (NRC) was established in 1975 under the Energy Reorganization Act of 1974. The NRC’s parent agency, theAtomic En- ergy Commission (AEC), was responsible for promoting and regulating civilian uses of nuclear energy following the development of nuclear weapons technology during World War II. At the time, public policy regarded nuclear energy as a resource with unlimited potential, promising inexpensive electricity and negligible environmental impact. Soon after the establishment ofthe AEC,critics saw a conflict between promoting nuclear energy and strictly regulating its safety, because the latter would lead to slower adoption of the technology. These concerns were eventually answered with the reorganization of 1974, which left the NRC with a mandate to protect public health and safety but without promo- tional responsibility. The NRC’s commissioners are appointed by thepresident and confirmed bythe Sen- ate, serving staggered five-year terms. The agency has broad authority to regulate nuclear technology. Impact on Resource Use NRC decisions have a major economic effect on the ability to replace conventional fuels with nuclear energy. Ifall safety measures proposed byenvironmental groups and nuclear critics were imposed, the money costs of nuclear power would usually be greater than those of alternative energy sources. Including only the safety measures considered necessary by the industry, money costs of nuclear power generally are less than those of alternatives. The NRC has regulatory responsibility for the disposal of nuclear power plant wastes, some of which remain significantly radioactive for thousands of years. The NRC’s safety decisions are complicated by the nature of nuclear risk: A major accident at a nuclear facility is estimated to be highly unlikely but to have potentially catastrophic consequences. As long as an accident ispossible, additionalsafety spendingis justi- fiable to further lower the probability or lessen the consequences. However, at lower probabilities, fur - ther reductions in accident danger become more and more costly. The NRC’s legislative mandate calls for Global Resources Nuclear Regulatory Commission • 837 . fuel for some of these new types of reactors, in part because it is far more common than uranium. India in particular has made the development of thorium as a fuel a major objective of its nuclear-power. Both slurriesareused inthe coating of paper. There are significant deposits of zinc and copper in the provinces of Trondheim and Røros. Shawncey Webb Global Resources Norway • 829 Further Reading Fagerberg,. raising of fish. The government funds 29 percent of the cost of research and development of aquaculture. In 2009, the Norwegian government established sixty-five new licenses for the farming of

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