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14 декабря, 2021
The fission effect in uranium was confirmed in laboratories from England to Japan, and its profound implications were well understood by all engaged in nuclear physics. In 1939, nuclear fission was seen as having two possible uses.
discovery, methodically and with patience. By 1938, the team had identified the half — lives of 10 unknown radioactive substances in uranium bombarded by neutrons.
On March 14, the political climate changed for the worse. Austria was annexed by Germany, and Lise Meitner became a German citizen. She had to leave quickly and surreptitiously, before she was arrested for being a Jew. Friends smuggled her across the border to Holland, and she made it out with enough money to buy lunch and with no possessions. She wound up working in a nuclear physics laboratory in Stockholm, Sweden, but she kept up with Hahn back at the laboratory in Germany by mail.
They met clandestinely in Copenhagen in November, planning a new set of neutron bombardment experiments, and the letters kept flowing. Hahn steadfastly believed that nuclear fission was impossible, in late December, Meitner convinced him that he had split uranium into two large fragments, one of which was barium, and with that realization history was made. Unfortunately, it was illegal for Otto Hahn to put Lise Meitner’s name on the paper describing the chemical findings as coinvestigator because of her religious affiliation. Meitner and her nephew, the nuclear physicist Otto Robert Frisch (1904-79), published a paper two months later giving the physical explanation of Hahn’s discovery and naming the effect "nuclear fission."
Lise Meitner died in Cambridge, England, in 1968 after a life of dedicated work in nuclear physics. Element 109, meitnerium, was named in her honor in 1997. The most stable known isotope of meitnerium has a half-life of 1.1 seconds.
The first application is a controllable source of constant power. Neutrons, which are necessary to cause the chain reaction effect, are ejected from a fissioning nucleus at high speed. They can be slowed down to a crawl by repeated collisions with surrounding light nuclei, and at the low speed the free neutrons can be captured by uranium nuclei, causing further fission. The act of being slowed down imparts energy to the light nuclei, and this material, known as the moderator, is then used as a heat — transfer medium. The process can be controlled easily, by balancing the number of neutrons being produced with the number of neutrons necessary to keep the chain reaction stable.
The second possible application is a superbomb. Neutrons produce fission at slow, thermal speed, but there is also fast fission from neutrons at the extreme high end of the speed range. Start a chain reaction in a large enough mass of pure uranium, with no intervening moderator material,
and the fission will run out of control. It happens with such speed and is such a huge explosion that it can destroy an entire city. The military purpose of this application was both obvious and terrifying, and it was also seen immediately.
In February 1940, Otto Frisch, Lise Meitner’s nephew, and Rudolph Peierls (1907-95) drafted a memorandum to the British Committee on the Scientific Survey of Air Defense, titled, “On the Construction of a ‘Superbomb’ Based on a Nuclear Chain Reaction in Uranium.” Similar memoranda were written in Germany, Japan, and the Soviet Union at about the same time.
Scientists in every country considering the military uses of nuclear fission realized that there was a problem with applying this effect. The useful fission seemed to occur in only one isotope of uranium, U-235, and it was only a small component of naturally occurring uranium. To build a bomb, the 235 isotope had to be nearly pure, and separating U-235 from U-238 was no simple process. In the long run, only the United States had the industrial volume, ability, and materials to achieve this huge task. On top of that, the United States had inherited a large portion of the nuclear physics talent from Europe, as it fled the threatening fascist governments. The United States, which had contributed little to the field of nuclear research, became the world’s center for it during World War II, and science, technology, and international affairs would be changed forever.
The discovery and application of nuclear power were among the most profound scientific accomplishments of the 20th century, beginning with tentative explorations of the structure of matter, expanding into a rapid succession of unexpected discoveries, and finally settling into a seamless transition from theoretical science to applied engineering. In that century everything changed, as follows:
^ Science changed from an academic pursuit to an industry.
^ The scale of mathematical modeling changed from predicting the action of a bouncing ball to predicting the actions of trillions of simultaneously bouncing neutrons.
^ The use of uranium changed from an occasional orange or green dye in ceramics to a major power fuel.
^ The concerns of public safety changed from boiler explosions on steamboats to nuclear reactor explosions on continents.
^ The concept of warfare changed from endangering soldiers on battlefields to endangering populations in cities.
The History of Nuclear Power describes the sequence of these changes, as science and technology rapidly matured more than 100 years and as the scale of civilization and its energy needs expanded. Sidebars supplement the historical narrative, providing interesting notes on many of the pioneering scientists involved in the development of nuclear science and technology, as well as notes on spin-off ideas and branching technologies. The narrative follows the pace of nuclear development, surging ahead faster than civilization could keep up with it, stumbling occasionally, finally pausing to assess and contemplate all that had been accomplished, and never looking back.
Nuclear power in the United States was in a quiescent state for three decades, neither developing forward nor shutting down, and delivering about 20 percent of the nations electrical power. Other technologies, such as electronics, computers, and communications systems, rushed ahead in this period, improving and innovating. The art of generating power by nuclear means stood stagnant, trying only to make electricity while
remaining out of the public eye. The situation is now changing in complex ways. There is a heightened awareness of global climate shifts, the chemical composition of air, and the finite nature of burnable fuels. These new concerns would seem to favor a renewed push for nuclear power production, among other nonpolluting methods, but there are multiple layers of public anxiety. We are worried about future weather patterns and a lack of gasoline, but we are also worried about long-lived radioactive contamination and the safety of nuclear reactor operations. As these issues are pondered, a heightened level of understanding of nuclear science and its applications will be important enough to affect career paths and college majors.
The History of Nuclear Power provides a fundamental introduction to this complicated subject. It follows a straight line down the middle of the larger subject of nuclear technology, concentrating on the development of light-water fission reactors as the dominant power source design, skirting other interesting technologies, such as hydrogen fusion reactors or space propulsion reactors. These and other important topics are covered in further volumes in the Nuclear Power multivolume set.
I have been taught the history of nuclear power by its participants. My graduate school professors in nuclear engineering worked on the atomic bomb project during World War II, the nuclear-powered strategic bomber, the nuclear rocket engines, and the space-borne power reactors. I entered the workplace just as these projects were disappearing over the horizon, but I found a new set of frontiers and participated in the second phase of the history of nuclear power. I bring my experience and the knowledge passed from my elders to this work, and I hope that you will find it fascinating.
Nuclear technology must be approached with an enhanced sense of industrial safety, unprecedented in the history of mechanical systems, and the issue of nuclear hazards will be present in any discussion or debate on nuclear subjects. The History of Nuclear Power demonstrates the speed with which it was necessary to adjust industrial mind-sets to this new level of safety consciousness, and specifically dangerous aspects of the technology will be treated in detail in further volumes of the series. The History of Nuclear Power also reveals the sudden shift in the center of gravity of the body of nuclear science to the United States immediately before World War II, as the world’s top scientists fled their homelands and universities in Europe to escape troubling political developments. This fortuitous concentration of genius in the United States, which was seen as an island of freedom and safety in an unsafe world, led to an unusually rapid development of nuclear technology. Unique aspects of this development were the military takeover of all nuclear science during World War II and the smooth transition from fanciful theories to working industrial systems and weapons of immense power. After the war, through creative engineering, important legislation, and political arm-twisting, this new weapons technology was transformed into a peaceful, civilian-controlled energy source. Such is the first century of nuclear power development. The second century may require a similar quantity of groundbreaking science, advanced engineering, statesmanship, global diplomacy, and an ability to plan for the future.
The History of Nuclear Power has been written as a stirring account of the genius, the hard work, and the pure luck needed to unlock the atomic nucleus and turn matter into energy for the student or the teacher who is interested in seeing the future through a study of the past. Technical details of the nuclear process are made understandable through clear explanations of terms and expressions used almost exclusively in nuclear science. Much of nuclear technology still uses the traditional, American system of units, with some archaic terms remaining in use. The crosssectional area of a nucleus, for example, is still universally and officially expressed in barns, and not in square centimeters, due to a purely historical fluke. An American scientist, upon first measuring the cross section of a uranium nucleus, exclaimed, “That’s as big as a barn!” Where appropriate, units are expressed in the international system, or SI, along with the American system. A glossary, chronology, and a list of current sources for further reading and research are included in the back matter.
On September 13, 1942, an important meeting of the Project S-1 Executive Committee was held. The United States was now fully engaged in the war, and it was time to move the atomic bomb project from a cautious and tentative rate of progress to full speed forward. Present at the meeting were Arthur Compton (1892-1962), director of S-1; Lyman Briggs (1874-1963), the former chairman of the Uranium Committee; James Conant (18931978), president of Harvard University; Ernest Lawrence, the cyclotron expert from Berkeley; Eger Murphree (1898-1962), petroleum chemist at Standard Oil; and Harold Urey (1893-1981), another chemist, but with a Nobel Prize. Complete secrecy was necessary, so the meeting was held deep in a forest in Monte Rio, California, in front of the massive stone fireplace in the clubhouse of the Bohemian Grove.
The Grove, populated by undisturbed redwoods more than 1,500 years old, is owned by the Bohemian Club, an exclusive, extremely secretive men’s club founded in 1872. Over the entrance is carved the motto: “Weaving Spiders Come Not Here.” A more secure venue could not be found. The urgent topic of discussion was fast neutrons.
A report sent from the MAUD Committee, the top secret British study of nuclear fission, had just come to light, and it detailed an important
finding. It had been known since 1939 that uranium-235 would fission under the influence of neutrons slowed to thermal speed, but there was another point on the spectrum of neutron energies where fission would also be initiated. It was at the opposite end of the range, where 1 MeV neutrons, fresh from the fissioning event, would also cause energy-releasing fissions. This fact was key to the development of nuclear weapons, because it meant that a bomb could be built small and light and carried by an airplane. Until then, it had been thought that any chain-reacting uranium explosion would have to be graphite-moderated, and the weapon would be the size of a small house and weigh many tons. Without the moderator, and using pure uranium-235, the explosive core could be as small as a pineapple.
The men in the meeting understood the implications of this new information, but they also realized that they were in over their heads. They decided to establish a new, centralized laboratory to do nothing but study fast neutrons. For the next couple of days, it was code-named Project Y, and they decided it should be run with military precision, speed, and efficiency by a West Point man. Four days later, Colonel Leslie Richard Groves (1896-1970) of the U. S. Army Corps of Engineers was assigned to run this new project. Born in Albany, New York, Leslie Groves was educated at the University of Washington, the Massachusetts Institute of Technology, and West Point, where he was fourth in the class of 1918. He had just completed a huge construction project, building the Pentagon military office building in Virginia, and was looking forward to a vacation.
Instead, he was promoted to brigadier general and handed a project called “Laboratory for the Development of Substitute Materials,” a name chosen for its misdirecting properties. Groves did not like the name. He changed it to the “Manhattan Engineers District,” for a nonexistent office of the Corps of Engineers, and seven days later he bought 52,000 acres (210 km2) of land in rural Tennessee, hidden between mountain ranges, called Oak Ridge. It would be given the prosaic name “Site X,” and his project would be headquartered there, far from prying eyes. Everyone except Groves would call it the “Manhattan Project.”
Nuclear physics was now on the fast track. Decisions and directives that had taken months to become effective before the war now took minutes to be implemented, and budgets that were in the thousands of dollars were now in the billions. New cities would be built from scratch in weeks, universities would be drained of science and engineering faculties, and even silver would be shipped out of the U. S. Treasury by the ton. It would
be an industrial application of pure science as the world had never seen, and it would be carried out in secret. Unlike Germany or any other place in Europe, the manufacturing plants and laboratories would not be subject to bombing, sabotage, or enemy observation.
The next chapter covers the intense three-year effort, beginning with construction projects in Tennessee, Washington State, and New Mexico, and ending with the unconditional surrender of the Empire of Japan. This unusual, government-sponsored endeavor would forever skew nuclear power, reminding everyone of bombing and unleashed radiation, but it would also give it a tremendous push.
By 1906, Rutherford was still at McGill University in Montreal puzzling over Philipp Lenard’s conjecture from 1903 concerning the void between atoms, and he was studying his newly discovered alpha particles. He was measuring the degree of deflection he could obtain using a strong magnetic field with alpha particles streaming through it. They were moving fast and were heavy, and to get a barely measurable deflection he had to use the most powerful magnet he could devise in the laboratory. His results were recorded on photographic film, showing where in space his beam of alphas landed after traversing the face of the magnet. He defined the beam using a narrow slit through a sheet of metal, and at one point he tried to improve the quality of the beam by putting a thin sheet of mica over part of the slit.
The mica was thin enough to allow alpha particles through, but the particles that came through the mica made an odd, blurred image on the film. As hard as it was to believe, the thin piece of mica was deflecting alpha particles through two degrees, and that was better than he could get using his best magnet. Rutherford made a calculation. To deflect alpha particles by two degrees would take an electrical field of 100 million volts per centimeter of mica. It was clear to him that the center of an atom had to be the source of very intense electrical forces. Alpha particle scattering required further study.
Back in Manchester in 1910, Rutherford set up his colleague Hans Geiger (1882-1945) and an undergraduate Ernest Marsden (1889-1970) to study this business of deflection of alpha particles through thin materials.
It would turn out to be a life-changing experience to be enshrined and known to physicists forevermore as “the Gold Foil Experiment.”
Geiger and Marsden were going to try Rutherfords scattering experiment with a lot of other materials besides mica. They planned to try alu-
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minum, silver, and platinum, all made thin enough for alpha particles to go through the samples, but first they would try gold because it was easiest to obtain in very thin samples. A vertical sheet of gold foil was set up. To count the alpha particles deflecting through the gold and note their positions they used a glass plate painted with zinc sulfide. It would glow or scintillate when hit with an alpha particle, and they would view it using an attached microscope with the lights turned off.
Next they needed a source of a beam of alpha particles. Radium was a convenient source, but it radiated alpha particles in all directions and they needed a tight beam. They built a special alpha source using a speck of radium at the end of a metal tube. The alpha particles would be absorbed in all directions in the tube except the direction leading right down the center. It seemed like a design that could not fail, but there was a problem. The tube was set so that it was aimed at the gold foil at a 45 degree angle. The pencil-thin beam was expected to deflect, going through the foil and coming out the other side in a spray four degrees wide, but there were alpha particles where there should be none, wide of the opening in the end of the alpha source tube. It appeared that the tube setup was faulty, and that alphas were somehow being emitted at odd angles by the tube. The two scientists tried to fix it. Nothing they tried seemed to work.
Rutherford wandered into the room to find out how it was going. Mars — den reported unsatisfactory results. The beam was too wide, and they were detecting alpha particles scattered widely. Rutherford had an idea. He told Marsden to look for alpha particles in front of the foil, instead of in back of the foil, where the beam was supposed to emerge. Marsden slid a thick, lead shield between the viewing screen and the alpha tube to make sure he was not looking at stray alphas out of the source and put his eye to the microscope, mounted at a 90-degree angle on the front of the gold foil. Marsden was astonished at what he saw in the eyepiece. Instead of simply being deflected by as much as two degrees by going through the gold, the alpha particles were being deflected backward, by an astonishing 90 degrees or more. He met Rutherford on the steps leading to his private room and broke the news. Rutherford was overjoyed. A piece of gold 0.00002 inches (0.00006 cm) thick was deflecting alpha particles through an angle that would require one enormous magnet. As Lord Rutherford recalled the event later, “It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you.”
Lenard’s observation concerning the extreme lack of substance in matter had been absolutely correct, and Rutherford quickly adjusted his
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concepts to match it. The alpha particles trying to run through the gold atoms in the thin foil were like comets approaching a thin galaxy of stars in outer space. Get too close to a star, and the comet will whip around it and come back in nearly the same direction in a tight, parabolic trajectory. The astronomical analogy was obvious, and Lord Rutherford proceeded to model his atoms as Sunlike nuclei having planetlike electrons spinning around them in elliptical orbits. It made a certain poetic sense that matter would be composed of tiny solar systems. The universe in its tiniest form was the same as the universe in its largest form.
In the normal day-to-day world, quantities such as speed, mass, and distance are smooth and infinitely divisible. Actions are predictable and reproducible. In the submicroscopic world of quantum mechanics, quantities are jerky and make sudden jumps from one value to another. Actions seem governed by probability, and randomness prevails.
Imagine a block of radioactive cobalt metal, for example. It is an absolutely certain prediction that in 5.272 years the rate of radiation production in this sample of cobalt will decrease by half, as the metal block produces a continuous stream oigamma rays. Cut the block in half, and lay aside one of the pieces. The size and the radiation production of the sample are now smaller, but it is still a piece of cobalt and the radiation will still decrease by exactly half in 5.272 years. Now cut the remaining piece in half, and push one half aside. Cut this new piece in half. In theory, this block of cobalt can be cut in half a seemingly infinite number of times, but eventually the block of cobalt is so small it is just two atoms of cobalt stuck together. Cut that in half, and the block consists of one atom of cobalt. That atom cannot be cut in half, or at least if it were then the results would no longer be two, smaller pieces of cobalt. Cut an atom of cobalt in half, and all the characteristics of cobalt are lost in the process. The atom cannot be evenly divided, as the nucleus contains 27 protons. The atom is therefore the smallest quantity in which cobalt can exist, and the metal is not infinitely divisible. This smallest possible bit is
the quantum of cobalt. Every quantity of cobalt is some integer multiple of this quantum, but in the macroscopic world, or the world at a scale with which we are familiar, the digital graininess of this material is so small it is not noticeable. There is a threshold. Above the threshold is the continuum of classical physics. Below the threshold is the discontinuous region of probabilistic action and quantum mechanics. There is no way to predict when one atom of radioactive cobalt will decay and send off a burst of radiation. The best prediction is that within 5.272 years the odds are 50-50 that the atom will undergo radioactive decay.
Quantum mechanics would provide a firm, theoretical basis and explanation for how the energy release from nuclear decay could be achieved. At full force, quantum mechanics would predict the energy-producing qualities of nonexistent elements and the properties of previously unknown subatomic particles. Eventually, quantum mechanics would be used to back step time in a forensic study of the beginning of the universe. This chapter will reveal some of the most crucial beginnings of quantum mechanics as it was used to push forward an understanding of the atomic nucleus. As the physicist who invented it once said, “If quantum mechanics hasn’t profoundly shocked you, you haven’t understood it yet.”
At the end of World War II, the U. S. government upgraded the existing, hastily constructed nuclear laboratories at Los Alamos, New Mexico, and Oak Ridge, Tennessee, and built several more across the country. Major labs were built in Brookhaven, New York, Livermore, California, Idaho Falls, Idaho, Aiken, South Carolina, and at Simi Hills, California.
At Simi Hills, overlooking the Simi Valley 30 miles (48 km) north of Los Angeles, the Santa Susana Field Laboratory (SSFL) was constructed on 2,668 acres (10.8 km2) of land. Its purpose was to test rocket engines, guided missiles, munitions, and nuclear reactors in what was then a sparsely populated area. As seemed usually the case in the 1950s, nuclear engineers were interested in exotic reactor designs using high-performance coolants, such as liquid sodium. A commercial nuclear power plant was developed at the SSFL. It was named the Sodium Reactor Experiment.
Sodium has some good properties as a reactor coolant, but it also has a few disadvantages. It does not absorb neutrons parasitically, nor does it boil away at anything but the highest temperatures, and it has excellent heat conduction. However, at low temperature it is a solid, locking everything immersed in it in a metallic block. It is opaque. You cannot simply look and see what is going on in a sodium-cooled reactor core. It also reacts vigorously with air or water vapor, and this means that it cannot be allowed to leak out into a room. Its compound with water is extremely corrosive and will quickly dissolve aluminum.
The sodium reactor experiment was brought to power operation in April 1957, and on July 12, 1957, its electrical output was switched into the California power grid, making it the first commercial nuclear power production reactor in the United States. For a short period of time, just long enough to prove the point, it supplied power to 1,100 homes in the Moorpark area of California. On July 13, 1959, the Sodium Reactor Experiment made another first. It became the first power-producing nuclear reactor in the United States to experience a core overheating.
The reactor was operating normally when it experienced a sudden power excursion, with the power level and temperature rising rapidly. With considerable effort, the reactor was brought under control and shut down. The cause of the excursion was baffling and was not determined, but the decision was made to ignore the problem as an unexplained anomaly and continue operating as if nothing had happened, so a few hours later the reactor was restarted and taken to operating power.
Subsequent reactor behavior seemed strange, and radiation alarms kept going off, so after 13 more days of wrestling with the controls the reactor was shut down for analysis. The operating crew discovered that almost one-third of the reactor core had melted, releasing radioactive fission products into the liquid metal coolant. Radioactive gases from the wrecked core were collected in holding tanks and then bled into the atmosphere over a period of several weeks. The problem had been caused by leaking seals in coolant pumps. When the seals failed, the coolant for the pump bearings leaked into the sodium coolant. The coolant was an exotic organic fluid, Tetralin, and it carbonized when it hit the sodium, blocking coolant passages. The blockage kept coolant from the fuel, and the cladding melted in the increased temperature. The reactivity of the graphitemoderated core improved without coolant, causing the power level to rise out of normal control.
There was a weakness in the reactor design, and a simple, predictable problem led to a major breakdown. Pump-seal coolant will eventually leak, as the moving parts experience wear. Any flow disruption of the molten sodium in the core would lead to a runaway, instead of an automatic, shutdown. A stronger design would allow anything that is capable of failure to fail without causing a larger problem, and a disturbance of the coolant should cause the reactor to revert to a safer condition and not a less safe condition. In retrospect, the operating procedures for the reactor were fundamentally wrong. When a problem with unknown characteristics arises, the reactor should not be restarted until the cause is known. These were the lessons learned from the Sodium Reactor Experiment meltdown. These lessons would require further reinforcement, but it was a beginning of the nuclear power learning process.
In parallel to the sodium reactor development at the SSFL, Admiral Hyman Rickover oversaw the naval reactors program for the AEC. His development of the power plant for the nuclear submarine Nautilus proved remarkably successful. Based on his pressurized water design,
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using ordinary water for both the reactor coolant and the neutron moderator, the naval reactors amassed a perfect safety record. No reactor in the U. S. Navy has ever experienced an accidental release of radioactive material. In Rickovers nuclear navy there has never been a reactor meltdown. Never has a sailor or the environment surrounding a nuclear-powered navy vessel been subjected to abnormal radiation due to a malfunction.
The navy, greatly pleased with the nuclear submarine program, ordered more submarines and nuclear-powered surface ships. The 10-megawatt Westinghouse reactor used in the Nautilus was upgraded into a 60-megawatt design for use in an ambitious Navy plan to build a nuclear-powered aircraft carrier. Under the auspices of Hyman Rickover in his role inside the AEC, the aircraft carrier engine design was modified
for use in a stationary, full-scale electric power plant, in a project proposed by the Duquesne Light Company.
On the Ohio River in Beaver County, Pennsylvania, about 25 miles (40 km) from Pittsburgh, the Shippingport Atomic Power Station was built, beginning on September 6,1954. It was the cornerstone of President
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Eisenhowers Atoms for Peace concept, and he turned the first shovelful of dirt at the groundbreaking ceremony. It cost only $72.5 million to build, because all the expensive up-front engineering had been paid for by the U. S. Navy.
It took 32 months to build the plant, and the reactor first started up at 4:30 a. m. on December 12, 1957. The plant was brought to full power 21 days later, after the correct operation of all systems had been checked and confirmed. After May 26, 1958, Shippingport was online and officially generating power. It was the worlds first full-scale atomic power plant devoted exclusively to peacetime uses. It generated electricity without a problem for 25 years, and it seemed to prove that nuclear power could be used safely and that it was more economical than a conventional plant. There was no need to constantly move train-cars of coal on and off site, and there was no smokestack pouring soot and carbon
The year 1939 was a critical turning point not only in the state of the world but also in the development of nuclear power. A worldwide economic depression had been in effect for 10 years, and the lack of investment resources did not encourage the development of an entirely new energy source. Although it was scientifically possible to achieve a self — sustaining nuclear reactor that would generate thermal power, it was financially impossible. There were innumerable engineering details to be worked out, and there were still scientific unknowns and blank spots in the theories.
The biggest problem was dealing with the very low concentration of a usable isotope of uranium, U-235, mixed in with an unusable isotope, U-238. As it occurs in nature, uranium contains only 0.7 percent of the fissionable isotope that could be used for power generation. Isotope separation, in which the concentration of U-235 in natural uranium could be improved, had been demonstrated only as laboratory setups involving countable numbers of atoms. To make practical nuclear fuel would require an industrial effort of such enormous scale it was out of the question for normal commerce.
This chapter focuses on the factors that made 1939 a pivotal year in the development of nuclear power. The components of this historical convergence include an ominous but ultimately false fear of atomic bomb construction in Germany, the discovery in Italy of neutron interactions at low
energies, a fortuitous transfer of nuclear physics expertise from Europe to the United States, and the development of an infrastructure for high — energy particle physics in California. In the middle of this frenzied race for nuclear fission, a second mode of nuclear energy production, fusion, was theorized into being. Although it seemed out of place, this theory completed the scientific understanding of energy from the nucleus, and its importance is undeniable.
One of humankinds first scientific discoveries was fire. At some distant unrecorded date it was found that dead organic matter, such as tree limbs, could be made to burn, and human beings grew to enjoy cooked food, lighted shelters, and a warmth that allowed comfortable living in cold climates.
Breaking the weak forces that hold the atoms of a stick of wood together makes heat. Breaking the powerful forces that hold the nuclei of a stick of uranium together makes millions of times more heat than simple burning. This principle of nuclear power is now well understood, scientifically accepted, and widely practiced, but it was a long effort to get to this point of knowledge. Before the power of the nucleus could be explored, or even contemplated, it was necessary to realize that matter is divided into atoms.
This chapter first will show the gradual realization of atomic structure, starting as a hypothetical philosophy in ancient times and eventually refining into more rigorous, practical theories in the 19th century, as the concept of matter divided into indestructible chemical elements became clear and the practice of formal science was established. The discussion then reveals that when it was confirmed that atoms can neither be created nor destroyed, it was found, by accident and experimentation, that pieces of an atom can be torn off, and various forms of radiation result from this action. Light and the newly discovered radio waves and X-rays were
found to be different manifestations of the same phenomenon, which is an electromagnetic radiation predicted to exist by a set of finely crafted mathematical equations. The chapter goes on to study the alarming discoveries near the end of the 19th century, when an additional source of a more powerful radiation was found, apparently coming from deep inside the atom and requiring no external stimulus.
Brigadier General Leslie R. Groves was presented with an enormous task. He had to lead and coordinate a project that would take newly discovered principles and theories of nuclear interactions and translate them into manufactured military weapons. The work had to be done under emergency conditions and in total secrecy, using scientists recently imported from enemy-held territory. He had multiple tasks to be done first, before anything else was done. He had to build three city-sized laboratories: Site W, in the desert in Washington State at Hanford on the Columbia River, would be built to produce usable quantities of an element that had never before existed, named plutonium. Site X, in Oak Ridge, Tennessee, would be built to separate a rare isotope from tons of uranium ore, one atom at a time. Site Y, built in the high desert in New Mexico at Los Alamos, would be the intersection point, where these two exotic materials would be fashioned into a new type of extremely powerful bomb.
Groves needed experts in fields that were not even invented yet. He needed people, materials, and money at a time when all three were in short supply, but most immediately he needed help. He saw a requirement for a top theoretical scientist in a management position to keep the continued nuclear research and development running fast and efficiently. His Manhattan Project needed a scientific director, and he chose Dr. J. Robert Oppenheimer (1904-67), a physicist from the University of California, Berkeley.
Oppenheimer and Groves were complete opposites. Groves was large and overweight and fond of eating a certain type of candy called turtles. He was a career military man, trained in the United States as an engineer, with experience in large construction projects. His political views were conservative, and his manner could be brusque and direct. Oppenheimer was thin and underfed, and eating was not his favorite activity. He was a career academic, trained at the University of Gottingen, and his experience was theoretical physics. His political views were socialist with communist leanings, and his manner could be arrogant and sarcastic. They were a perfect match. Both became driven by the project. The two became good friends. When the war closed, they would share the credit for having led a magnificent job and the blame for having unleashed a dangerous product.
In 1879, most physics was experimental, and Max Karl Ernst Planck, Ph. D. in physics, found himself the only theorist in the Berlin Physical Society. A principle or finding that was first predicted mathematically was considered “spooky” in this German gathering, and purely theoretical studies had yet to achieve their full recognition as an essential part of the advancement of science. Still, in 1899, Planck won some funding from a consortium of electrical companies to discover how to derive the most light from lightbulbs using the least amount of power.
The problem to be solved boiled down to a central question: How does the intensity of the light emitted by a heated “black body,” or a perfect light-absorber, depend on the frequency, or color, of the light and the temperature of the body? There had been unsuccessful explanations of black — body radiation, and many experimental results had been accumulated. Approaching the problem from a mathematical end, Planck found, to his despair, that the possible explanations for an energy-frequency relationship all seemed to center on the statistical mechanics studies of an Aus-
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trian physicist named Ludwig Boltzmann (1844-1906). Planck and many of his fellow physicists at the time held a strong aversion to these probabilistic, statistics-based interpretations. Deeply suspicious of the philosophical and physical implications of his own work, Planck sacrificed his convictions and derived an important equation:
E = hv
E is the energy of a photon, which is directly proportional to the frequency, v, of the photon. A constant, h, completes the conversion. The energy of light is dependent only on its frequency. The startling implication is that a light beam of a given frequency, v, cannot be divided down
any lower than hv. Any further division, and the beam is no longer light. An intensity, or quantity, of light is simply an integer multiple of hv, but h is so small we do not normally notice any digital jump in brightness. The constant, h, became known as Plancks action quantum, or simply Planck’s constant. The equation proved accurate in all experimental confirmations.
Although he received the Nobel Prize in physics in 1918 for having derived this formula, Max Planck had a difficult time believing in his own work. The concept of quantized energy destroyed his understanding of classical theory, and he was never able to accept it as a reality. Other stubborn, traditional physicists simply gave Planck’s constant a value of zero and continued as if nothing had changed. Albert Einstein (1879-1955), a forward- thinking theoretical physicist in Germany, would explain the equation in his 1905 paper as an expression of light quanta, or photons, which were tiny, discrete particles of light. To the unending despair of both Einstein and Planck, quantum mechanics was born.
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Although Einstein was disturbed by quantum mechanics, he gave birth to it with his Nobel Prize-winning theory of the photoelectric effect in 1905. (Popperfoto/Getty Images)
The construction, ownership, and operation of civilian nuclear power plants are conducted under permanent rules and regulations set out in the Code of Federal Regulations and published in the Federal Register.
Nuclear power is regulated under Title 10 of the Code of Federal Regulations, which covers all issues of energy. Part 50 of Title 10 covers “Domestic Licensing of Production and Utilization Facilities," and Section 34 of Part 50 is concerned with “Contents of Applications; Technical information.” Paragraph (a) of Section 34, or 10 CFR 50.34(a), states that an application for a nuclear power plant construction permit must include a preliminary safety analysis report (PSAR), and 10 CFR 50.34(b) further specifies that an application for an operator’s license for a nuclear plant must include a final safety analysis report (FSAR).
The PSAR is an accounting of the engineering and operating procedures of a nuclear power plant pertaining to safety features or the handling of emergencies. This specification covers 12 points of nuclear power plant safety:
A A description and safety assessment of the site on which the plant is to be located, the intended power level and an inventory of on-site radioactive materials, a description of unique or unusual safety features of the facility, a description of radiation barriers that will be in place, and an assurance that an individual standing at the outer fence will not receive a hazardous dose of radiation in the event of the worst possible accident.
dioxide into the air. It had a cooling tower, just as any steam-operated plant would have, whether the heat was generated by burning coal or nuclear fission.
NUCLEAR POWER BECOMES COMMERCIAL
Construction was begun in 1953 on the Calder Hall nuclear plant at Sellafield in Great Britain, and it proved to be a highly reliable power source. It was first connected to the power grid on August 27, 1956, and the plant was formally opened by Queen Elizabeth II on October 17,1956. When it finally closed down on March 31, 2003, the first nuclear plant to
A A summary description of the plant, stressing unusual features and safety considerations.
A The preliminary design of the plant.
A An analysis of the design and performance of the structures, systems, and components of the plant, so that the risk to public health can be assessed. Emphasis is given to the emergency core cooling system, or ECCS.
A An identification of items that are of particular interest for the evaluation of the safety of the plant.
A A plan for the organization of the plant, the training of personnel, and rules for the conduct of operations.
A A description of the quality assurance program.
A An identification of any features of the plant that may require research and development.
A The technical qualifications of the applicant, or the organization applying to build a nuclear plant.
A A discussion of plans for dealing with emergencies.
A A discussion of possible hazards to the structures or components of the plant due to the construction features, and administrative controls that will be in effect during construction.
A Assurance that the plant will be built to withstand an earthquake.
Filing a PSAR is the first step in the paperwork necessary to build a nuclear power plant. From there, the procedure gets complicated.
deliver commercial power had been in constant use for 47 years without incident. Although it generated power, the Calder Hall reactor’s first intention was to produce plutonium for military purposes. This component of the Calder Hall mission was deleted in 1995, when the United Kingdom ceased nuclear weapons production.
With the success of Calder Hall and Nautilus in the United States, the British government decided to design and build its own submarine reactor. The result of the effort was too big to fit in a naval vessel, but the British advanced gas-cooled reactor would become another successful public utility power source. The gas-cooled reactor, called “the golf ball” for its round shape, was a step forward in the sophistication of the economical
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The Calder Hall Unit 1 at Sellafield, England. This was the first reactor to generate significant electrical power, but its graphite-moderated, gas-cooled design is now considered obsolete.
(Sellafield, Ltd.)
graphite-moderated reactor designs preferred by the British. The coolant was carbon dioxide gas, blown through channels bored in the graphite pile, and it was a good design for safety. The carbon dioxide was nonflammable, and it could not flash explosively from liquid to gas, as could water.
With all the effort to keep down the cost of the nuclear-generating plants, the British government found that it still cost 25 percent more to produce power by nuclear means than it cost to burn coal, even given the bonus of plutonium production. The government, seeing a larger picture, decided in 1960 to promote nuclear power as an alternative to coal production so that all the fortunes of the United Kingdom would not depend
on a single power source. Having an alternate source of electricity on the power grid would give them bargaining power against the coal miners’ unions, which had given them reason to be concerned, beginning with a general coal miners’ strike in 1926. In the longer view, the amount of coal that can be economical extracted in Great Britain is fixed and will not last forever. Nuclear fuel has a much longer life span.
The British nuclear industry built 11 power plants using variations and improvements of the original Calder Hall Magnox reactor. Two Magnox reactors were exported, one to Latina, Italy, and one to Tokai Mura, Japan. Nine reactors were built in France looking suspiciously like British Magnox designs, and three were built surreptitiously in North Korea using the declassified Calder Hall Magnox blueprints. All of these plants are now shut down. There are now seven nuclear plants operating in the United Kingdom. Six are advanced gas-cooled reactors, based loosely on the Magnox design, but now using enriched uranium oxide fuel. One is a standard Westinghouse pressurized water reactor, as pioneered by the Nautilus submarine program.
In a parallel program of nuclear engineering independence, Canada developed its own unique form of nuclear power plant. Great Britain avoided the high cost of building and running uranium enrichment facilities by purposefully designing reactors with high-efficiency graphite moderation. Canada wished also to avoid the cost of enrichment but chose heavy water as the high-efficiency moderator. This was the strategy that Germany had hoped to use during World War II, but Canada in the late 1950s assembled a partnership among Atomic Energy of Canada Limited and several private industries. They pooled resources and developed the CANDU, or CANada Deuterium Uranium, power plant.
Unlike the United States, Canada lacked the heavy industry necessary to build large steel pressure vessels that are used in pressurized and boiling water reactors. Instead, the heavy water moderator in a CANDU is contained in a low-pressure tank called the calandria, and the fuel is enclosed in small-diameter zirconium tubes. The tubes, which are easy to fabricate, conduct heavy water through the fuel at high temperature and pressure. The Canadian design is thus a pressurized water reactor that uses heavy water in the primary loop, through the fuel, and ordinary or light water through the secondary loop, making steam for the power — turbines. Refueling, which must be frequent due to the low U-235 content, is accomplished by automatic machines, pushing new fuel through one end of the reactor and catching it as it falls out the other.
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The first CANDU was built in 1962 in Rolphton, Ontario, and it ran for 25 years at low power, proving the concept of a heavy water power reactor. A second CANDU was built at Douglas Point in 1968, and further expansion in Canada and foreign sales have put 29 CANDU reactors in operation. There are 17 in Canada, and there are also CANDU reactors operating in South Korea, China, India, Argentina, Romania, and Pakistan. India has built 13 CANDU-derivative power plants without Canadian assistance.
A disadvantage to the CANDU design is the high cost of construction and building materials. Heavy water of sufficient purity costs about $1 per gram, and several metric tons are required in one reactor. As is the case with most nuclear reactor designs, the capital cost of building the power plant is 65 percent of the lifetime cost of producing power, with the cost of the fuel being less than 10 percent.
Other reactor designs have been tried with less success. Experimental reactors using plutonium-breeder technology or liquid-metal coolants, while having interesting potential for an economy in which uranium is not available, have proven less than practical for commercial power
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production. Some designs, such as the infamous Soviet RBMK graphite pile, have a lack of inherent safety characteristic and are being phased out as the plants reach the end of operating life. In general, the pressurized water reactors (PWRs) have proven to be the preferred design for practical power sourcing, with the boiling water reactor (BWR) a second choice. Japan, with 55 nuclear reactors in 17 power plants, is representative of the international commitment to alternative base power supplies. Of these 17 power plants, four were knocked out of commission by the Tohoku earthquake of 2011. One, the Fukushima I Nuclear Power Station, was too damaged to be brought back into service.
France, where approximately 80 percent of the national electrical power is produced by nuclear fission, has 16 nuclear power plants, mostly PWRs. Frances fast breeder reactor, the Superphoenix Nuclear Power Station, has the distinction of being the only commercial power plant to come under rocket attack by an eco-pacifist group. In 1982, five exploding warheads were fired into the reactor containment building using a Soviet-made rocket launcher. Credit for the attack was taken by the Swiss Green Party. The Superphoenix was shut down in 1997 because of nagging problems with the 6,063 tons (5,500 metric tons) of liquid sodium coolant leaking onto the floor.
Germany has 14 nuclear power plants, Russia has 10, and the United States has 51. A power plant usually has more than one reactor, and in the
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United States there are 104 reactors. Nuclear plants in the United States produce just under 20 percent of the total electricity used by consumers. The lone sodium-cooled fast breeder reactor in the United States
commercial power grid, Fermi I near Monroe, Michigan, suffered a meltdown in 1966 and proved too expensive to be of practical use.
A single nuclear plant can produce as little continuous power as 137 megawatts by the KANUPP reactor in Pakistan or as much as 5,700 megawatts by the Zaporizhzhia Nuclear Power Plant in the Ukraine. There are modest components of the national power supply dedicated to nuclear methods in Finland, Hungary, Brazil, Mexico, Bulgaria, Argentina, the Philippines, Romania, and South Africa. Spain has an impressive eight nuclear power plants, Sweden three, and Switzerland four.