Sarov

Nizhni Novgorod Region

Gymnasia № 2

The topic of project:

Nuclear Renaissance: Benefits vs. Risks

Student: Teacher:

Sergei Fadeev Tatiana Satyukova

Grade 10 Gymnasia # 2

Gymnasia # 2 Sarov

Sarov

2007-2008

Nuclear Renaissance: Benefits vs. Risks

Benchmark I

There is a renewed interest in nuclear energy, even a new term “ Nuclear Renaissance” has appeared. The topic is extremely interesting not only for the grown-ups but for the young people of my age as well.

In Benchmark I, in my investigations, I will try to examine the objectives from the point of view of the scientific and environmental, social and cultural, economic, political and geopolitical domains to demonstrate a comprehensive understanding and comparison of conventional energy and nuclear energy.

Part 1.

To start with I need to build a glossary of terms and phrases related to energy sources to be able to describe the important sources of energy in use in countries of the world today.

“Renaissance- a new interest in something, especially a particular form of art, music etc, that has not been popular for a long period” (Longman Dictionary of American English, Third edition 2002)

“Nuclear- relating to or involving the nucleus (central part) of an atom, or the energy produced when the nucleus of an atom is either split or joined with the nucleus of another atom” (Longman Pearson Exam Coach Dictionary,2005)

-relating to or involving the use of weapons that use nuclear energy

“Power - energy that can be used to make a machine work or to make electricity.” (Longman Dictionary of American English, Third edition 2002)

“Benefit- an advantage, improvement, or help that you get from something

Risk- the possibility that something bad, unpleasant, or dangerous may happen”(Longman Dictionary of American English, Third edition 2002)

“Atom- the smallest part of an element that can exist alone or can combine with other substances to form a molecule”. (Longman Pearson Exam Coach Dictionary, 2005)

“Power- energy that can be used to make a machine work or to make electricity”(Longman Pearson Exam Coach Dictionary,2005)

“Nuclear energy-the power that comes from splitting atoms, used for making electricity and the explosive part of some bombs”(Longman Pearson Exam Coach Dictionary,2005)

“Nuclear power- power, usually in the form of electricity, produced from

Nuclear power is the use of nuclear reactions to generate power, usually electrical, such as in an atomic battery or a nuclear power plant.” (http://en.wikipedia.org )

“Proliferation- the process by which an organism produces others of its kind; breeding, propagation, procreation, reproduction” http://en.wiktionary.org/wiki/proliferation

“Nonproliferation- the limiting of the number of nuclear or chemical weapons in the world, especially by stopping countries that do not yet have them from developing them”. (Longman Pearson Exam Coach Dictionary,2005)

“Safety- when someone or something is safe from danger or harm”(www.britannica.com).

“Security- protection from change, risks, or bad situations”(Longman Dictionary of American English, Third edition 2002,)

“Terrorism- the use of violence such as bombing, shooting, or kidnapping to obtain political demands such as making a government do something”

“Nuclear terrorism- denotes the use, or threat of the use, of nuclear weapons or radiological weapons in acts of terrorism, including attacks against facilities where radioactive materials are present. In legal terms, nuclear terrorism is an offense committed if a person unlawfully and intentionally “uses in any way radioactive material … with the intent to cause death or serious bodily injury”, according to International conventions” http://en.wikipedia.org/wiki/Nuclear_terrorism

“Nuclear reactor - is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate, as opposed to a nuclear bomb A nuclear reactor, in which the chain reaction occurs in a fraction of a second and is uncontrolled causing an explosion” http://en.wikipedia.org/wiki/Nuclear_power_reactor

Almost each student knows something about today energy sources. For the most part, they are composed of fossil fuels, water power, and nuclear energy. To a lesser extent, wood, solar, wind, tidal, geothermal and chemical resources are used.

Everyone will agree that in our modern industrial society we consume vast amounts of energy to make our daily life more productive, more comfortable and enjoyable. All of us use energy every day - for heat and light in living and working areas, cooking, transportation, manufacturing, and entertainment. The choices we make about how we use energy - choosing to buy energy efficient appliances or turning machines off when we’re not using them - impact our environment and our lives.

Energy comes from several different sources. These sources can be split into two main categories: non-renewable and renewable. Non-renewable types of energy include the three major types of fossil fuels – coal, oil and natural gas. Fossil fuels supply more than 90% of the world's energy. Oil leads with a share of about 40 percent of total world energy consumption, followed by coal (24 percent) and natural gas (22 percent). All of these are burned to produce power.

(www.ccs.neu.edu/home/gene/peakoil)

Let’s describe the major sources and begin with coal. Coal is a fossil fuel extracted from the ground either by underground mining or strip mining. It is a readily combustible black or brownish-black sedimentary rock. Rather often it is associated with the Industrial Revolution, coal remains an enormously important fuel and is the most common source of electricity world-wide. In the United States, for example, the burning of coal generates over half the electricity consumed by the nation.

Coal reserves are estimated to last 100 years or more. It’s an interesting fact that 78% of the world's proved reserves of coal is in the U.S., Russia, China, India, Australia and Germany. China is the largest producer of coal, followed by the United States. Coal can be directly burned or converted to a liquid fuel. The difficulty with coal is that it releases much larger amounts of carbon dioxide into the atmosphere than any other energy source. But this is of the largest causes of global warming. For this and other reasons, the world has moved away from coal. It is now generally agreed that global warming due to human beings is a fact. It is still debated whether the degree of global warming by human beings is sufficient to melt the polar ice caps and flood many cities. If the world switches to coal for its primary energy source, then there will no longer be a debate about global warming. It will be a certainty. Beyond that, there is also a Fischer-Tropf process to convert coal to liquids. However, the conversion process, alone, produces large quantities of carbon dioxide, and some of the same issues apply as for the gas-to-liquids technology for natural gas. (/www.ccs.neu.edu/home/gene/peakoil/)

As we know, natural gas is a finite resource, but its production plateau for the world may be ten years off or further. Nowadays about 54% of the world's proven reserves is in Russia, Iran and Qatar. But North America has also reached its plateau now, and may become a major importer soon. Natural gas can be and is imported from other continents by first lowering the temperature to -161 Celsius to form liquefied natural gas. There are (expensive) schemes to use natural gas as fuel instead of gasoline. See, for example, Conoco's Gas-To-Liquids project with a demonstration plant to produce 400 barrels of oil per day. Some estimate that this process could become economic with sustained oil prices of at least 40 dollars per barrel. This process, if pursued seriously, buys some transition time after the peak production of oil is reached. However, many years are needed to build the full-scale infrastructure for gas-to-liquids. Further, current natural gas production is only 2/3 of oil production (based on energy content). Switching from oil to natural gas would exhaust natural gas much faster, bringing even closer the peak in natural gas production. (www.ccs.neu.edu/home/gene/peakoil)

The petroleum industry has especially big value. Nowadays oil is extracted more than in 80 countries of the world. More than 40 % of oil is imported by OPEK countries, that’s why we can’t deny important role of these countries in world economy, even though most of them are not very high developed. Still most part of oil is extracted in African countries. Among them: Nigeria, which is a major oil supplier to both Western Europe and the United States. The country produces roughly 2.5 million barrels per day. Angola - the second-largest oil producer in sub-Saharan Africa after Nigeria, with oil production expected to reach 2 million barrels per day by 2008; and Republic of Congo, where the oil industry accounted for about 80 percent of the country’s revenues, and nearly 90 percent of its total export earnings. Nowdays the world’s top five crude oil producing countries are: 1-Saudi Arabia, 2- Russia, 3-United States of America, 4- Iran, 5- China and Mexico. (www.cfr.org, www.eia.doe.gov/kids/energyfacts/sources/non-renewable/oil)

We have used running water as an energy source for thousands of years, mainly to grind corn.The first house in the world to be lit by hydroelectricity was Cragside House, in Northumberland, England, in 1878. In 1882 on the Fox river, in the USA, hydroelectricity produced enough power to light two paper mills and a house. Nowadays there are many hydro-electric power stations, providing around 20% of the world's electricity. The name comes from "hydro", the Greek word for water. A dam is built to trap water, usually in a valley where there is an existing lake. Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators. Notice that the dam is much thicker at the bottom than at the top, because the pressure of the water increases with depth. Hydro-electric power stations can produce a great deal of power very cheaply. When it was first built, the huge "Hoover Dam", on the Colorado river, supplied much of the electricity for the city of Las Vegas; however now Las Vegas has grown so much, the city gets most of its energy from other sources.Although there are many suitable sites around the world, hydro-electric dams are very expensive to build. However, once the station is built, the water comes free of charge, and there is no waste or pollution. (www.nationaltrust.org.uk)

Nuclear power is generated using Uranium, which is a metal mined in various parts of the world. The first large-scale nuclear power station opened at Calder Hall in Cumbria, England, in 1956. Some military ships and submarines have nuclear power plants for engines. Nuclear power produces around 11% of the world's energy needs, and produces huge amounts of energy from small amounts of fuel, without the pollution that you'd get from burning fossil fuels. (www.nationaltrust.org.uk)

The world has 100 years or more of uranium reserves (especially if the world also uses breeder reactors to reprocess expended fuel) . The United States, France, Japan, Germany, Russia and South Korea produce 74% of the world's nuclear energy, as electricity. Since Three Mile Island in the United States and Chernobyl in the Soviet Union, the world has been nervous about allowing each individual nation to regulate its own nuclear industry. There are also worries about nuclear weapon proliferation. Nuclear reactors produce nuclear waste with trace amounts of plutonium and fissionable uranium. If every country has nuclear reactors, then every country has the potential to reprocess the expended nuclear fuel into weapons-grade uranium or plutonium. It also opens the possibility for smaller groups to steal such expended fuel for reprocessing elsewhere. If countries use breeder reactors to reprocess expended fuel, then it is even easier to convert a portion into weapons-grade uranium or plutonium. (www.ccs.neu.edu/home/gene/peakoil)

Solar Energy is used widely across the globe. Unfortunately, as currently utilized, this source of energy fails to produce enough power with which to run towns or buildings. It is used mainly on a household level. The sun's rays are collected with flat-plate collectors mounted in an area with good direct sunlight. The collectors convert that solar energy into heat energy. Electricity is produced by solar, or photovoltaic cells, typically providing heat for both living spaces and water. Solar power produces clean and virtually unlimited power, but it is not yet economically suitable as a major source of electricity for large scale energy needs. Solar power generation is limited by the amount of sunlight available. Since it is adversely affected by bad weather and darkness, it is most suited to regions with many long cloud-free days. (www.library.thinkquest.org/21794/energysources)

Geothermal power is another clean alternative to fossil fuels. Steam power is produced whenever water is channeled onto the incredibly hot rocks that lie beneath the surface of the earth. Power companies drill deep into the earth and generate energy with the steam that is given off. Geothermal energy is already being produced in some European and Asian countries, as well as in the United States. (www.library.thinkquest.org/21794/energysources)

Tidal energy is produced by water as it flows from high tide to low tide. As the water rises, a dam closes in the bay. Then when the tide falls, the water is released and flows through a turbine generating energy. The only disadvantage with this system is that energy is only being produced when water in the tide is falling. (www.library.thinkquest.org/21794/energysources)

So, these are the most important energy sources, which are used in different countries all over the world and play important part in humanity life.

4. Now I will try to give exmples of how some countries rely on different sources of energy.

Canada,for example, was the fifth-largest energy producer in the world in 1999, behind the United States, Russia, China, and Saudi Arabia. But over the past two decades, Canada has become a significant net energy exporter. In 1999, about 30% of Canadian energy production was exported, with the United States by far the main customer. January-November 2000, the United States imported more oil (including crude oil and petroleum products) from Canada than from any other country. The United States also consumes large amounts of Canadian natural gas, which accounted for 94% of U.S. gas imports and 14% of U.S. gas consumption in the first half of 2000. In 1999, about 36% of Canada's primary energy production was natural gas, followed by oil (23%), hydropower (20%), coal (11%), and nuclear power (4%). About two-thirds of Canada's energy is produced in the province of Alberta.

Poland, the Czech Republic, the Slovak Republic (commonly referred to as Slovakia), and Hungary are members of the Visegrad Group, created in February 1991 at the northern Hungarian town of Visegrad. The Visegrad countries are neither large producers nor consumers of energy. Coal is the single abundant fossil fuel in the region, with only Poland and the Czech Republic having significant quantities. The Visegrad countries therefore import most of their crude oil and natural gas requirements, mainly from Russia. The exceptions are Poland and Hungary, which met roughly 39% and 24% of their natural gas consumption demand with domestic sources in 2001. This dependence on Russian gas and oil imports is also a point of contention for these countries, particularly as they privatize their energy markets in preparation for EU accession. Some government officials have argued that giving up stakes in state energy companies will compromise national energy security, as the state will no longer have control over production. During the last decade, the Visegrad countries have tried to diversify their energy supplies to reduce their dependence on Russia. The strategic importance of the region, however, lies largely in the crude oil and natural gas pipelines which traverse the Visegrad countries on their way to Western Europe. As the Visegrad countries strive to meet EU membership criteria, natural gas is becoming increasingly important to the region's energy mix. Increased consumption of natural gas, as an alternative to coal, is considered to be a key component of the region's plan to meet the stricter EU regulations.

“Slovakia's per capita natural gas consumption is the highest among the Visegrad Group countries. About 80% of Slovak households are connected to the natural gas network. In the Czech Republic, natural gas consumption has increased by 35% between 1993 and 2001. In 2001, natural gas represented about 43% of total energy consumption in Hungary and 13% in Poland. Coal is the most prevalent energy source in the Visegrad countries, although its role as a fuel and an industry is declining. Poland is the exception, where coal accounted for 93% of the country's primary energy production in 2001, and remains one of the country's most important employers. Coal also remains significant in the Czech Republic, where it constituted 47.7% of the primary energy consumption. The Czech Republic has two nuclear power plants, Dukovany and Temelín. After years of delay, on October 9, 2000, the Czech Nuclear Safety Authority cleared Temelín nuclear for operation, located only 37 miles from the Austrian border. The first reactor was connected to the national grid in December 2000. However, the reactor has been shut down a number of times due to technical problems. The second unit of the Czech Temelín nuclear power plant was put into trial operation on April 18, 2003. The two units are expected to reach 100% of their operational capacity at the end of April 2003. When the plant is fully operative, it will provide over 20% of the Czech Republic's power needs”. (www.eia.doe.gov/emeu/cabs)

France has 59 nuclear reactors operated by Electricité de France (EdF) with total capacity of over 63 GWe, supplying over 430 billion kWh per year of electricity, 78% of the total generated there. In 2005 French electricity generation was 549 billion kWh net and consumption 482 billion kWh - 7700 kWh per person. Over the last decade France has exported 60-70 billion kWh net each year and EdF expects exports to continue at 65-70 TWh/yr.

The present situation is due to the French government deciding in 1974, just after the first oil shock, to expand rapidly the country's nuclear power capacity. This decision was taken in the context of France having substantial heavy engineering expertise but few indigenous energy resources. Nuclear energy, with the fuel cost being a relatively small part of the overall cost, made good sense in minimising imports and achieving greater energy security.

As a result of the 1974 decision, France now claims a substantial level of energy independence and almost the lowest cost electricity in Europe. It also has an extremely low level of CO2 emissions per capita from electricity generation, since over 90% of its electricity is nuclear or hydro.

With the years there were some changes in the use of energy sources from, for example, coal to oil to nuclear energy in different countries of the world.

Germany: German industrial development in the 19th century was fueled by coal. The use of coal declined in the 1970s and 1980s. However, East German brown coal remained important into the early 21st century for electricity production and as fuel, despite being a major source of air pollution. Petroleum and hydroelectric power were only a small source of public electricity production, but were major energy sources for heating and manufacturing processes.

“German dependence on petroleum imports, the oil crisis of the 1970s, and an expanding appetite for more energy shifted attention to the potential of nuclear energy. By the mid-1980s, 19 nuclear plants were supplying 36 percent of the public electricity needs in West Germany, and more plants were in the planning stage. Following the Chernobyl’ nuclear disaster in 1986, however, massive environmental protests stiffened public resistance to nuclear energy. Further construction of nuclear power facilities was halted for fear of accidents and lawsuits and because of the difficulties of disposing of the radioactive waste. Instead, West Germany embarked on a program of energy savings, including increasing the efficiency of automobile engines and heating plants. Alternative and renewable sources of energy, such as wind, solar, and geothermal energy, have also been developed, but there is little hope that they could ever supply a major part of Germany’s huge needs.

Nuclear plants still provide 28.13 percent of the nation’s electricity. While many reactors in Germany were shut down, there were 17 plants that continued to function in 2006.” (www.encarta.msn.com/encyclopedia_761561465)

France is Europe's second-largest power market, exceeded only by Germany. During the 1950s France became increasingly dependent on outside sources for petroleum. Although petroleum and natural gas continued to be produced in France itself (as they are today), the nation came to rely almost entirely on imports from oil fields of the Middle East, putting a heavy strain on the country's foreign exchange reserves. Discoveries of large supplies of natural gas and petroleum in the Sahara Desert changed the outlook radically; in 1967 France was able to meet almost half its fuel needs from countries within the franc zone. Petroleum production from the Saharan fields rose spectacularly from 8.7 million tons in 1960 to 53 million tons in 1970. Although France lost title to the Saharan deposits after Algerian independence, arrangements were made with the Algerian government to keep up the flow of oil to France.

Developments in the 1970s exposed the limitations of this strategy. Algeria took controlling interest in French oil company subsidiaries in 1971. The oil shocks of the mid- and late 1970s drove France's fuel and energy imports up; in 1975, fuel imports accounted for 22.9% of all imports. In response, France began an energy conservation program, but oil consumption continued to increase between 1973 and 1980, when fuel imports made up 26.6% of total imports. As of 2001, oil consumption was 2 million barrels per day, of which 1.9 million were imported. In the same year, France's oil reserves were estimated at 240 million barrels. Mergers involving France's top oil companies in 1999 and 2000 created the fourth-largest oil company in the world, TotalFinaElf.

The burden of fossil fuel alternatives falls mainly, but not entirely, on nuclear power. France has become the world's leading producer of nuclear power per capita, with the world's second-greatest nuclear power capacity (exceeded only by the United States). Like other forms of power production and distribution, atomic energy is controlled by the state. In the late 1990s, nuclear power was still a subject of heated national debate as public opinion turned against the former goal of 100% nuclear-powered energy. France is Europe's second-largest power market, exceeded only by Germany. In 2001, total installed power capacity was 111.3 million kW. Most major generating plants are administered by Électricité de France, the state-owned power authority, which produces and distributes over 95% of the country's electricity. Of the total power production of 511.1 billion kWh in 2000, over 77% came from France's 57 nuclear plants, about 13% from hydroelectric power, and under 10% from fossil fuels.

A tidal power plant has been in operation at Rance, in Brittany, since 1967, and the world's first solar furnace was built at Odeillo in 1969. In addition, some dwellings were being equipped with solar converters, and some were being at least partially heated by geothermal sources. Since 1914, Paris has been burning its garbage to provide heat; by 1981, trash burning was supplying over 30% of the city's heating needs. (www.nationsencyclopedia.com/Europe/France)

www.greenpeace.org/usa/photosvideos/photos/doel-steam-generator

It’s a pity that I didn’t have an opportunity to visit a nuclear power plant, but in April of 2004 Elena Ivanovna Tarakanova, the expert in a labour safety, visited Doel Nuclear power plant at the river Scheldt in Antwerp, Belgium, which is situated not far away from Brussel.( Belgium has seven nuclear reactors generating more than half of its electricity. Its first commercial nuclear power reactor began operating in 1974.)

There she found out that nuclear power plant is served only by 400 people, who work in 4 shifts, though it supplies with energy about 15 European countries! Another fact, that really shocked her there, was that there was almost no dust and many different animals lived near the station. Also, the government of Belgium advirtises safety and Ecological cleanliness of nuclear energy: pupils of different schools and kindergartens come on excursions to this plant and learn a lot about advantages of this kind of energy.

Belgium is a party to the Nuclear Non-Proliferation Treaty (NPT) since 1975 as a non-nuclear weapons state. It is member of the Nuclear Suppliers' Group. The Additional Protocol in relation to its safeguards agreements with the IAEA was signed in 1998 and came into force in 2004.

Part 2.

Now I’ll try to demonstrate my understanding of the processes involved in the production of nuclear energy in countries around the world. And I will start with the description of the nuclear fuel cycle.

As we know from the lessons of physics nuclear fuel cycle starts when uranium is mined. Uranium ore ( pict. 1) is the principal raw material which must be sent for the enrichment and fuel fabrication.–In the form of Yellowcake ( pict. 2) it is transported to an enrichment plant . Enriched and manufactured( pict.3) to nuclear fuel it is delivered to a Nuclear power plant. Then comes a question- weather to throw it away or to recycle it. So, after the usage in the power plant the spent fuel is delivered to a reprocessing plant or to a final repository for geological disposition. In reprocessing 95% of spent fuel can be recycled to be returned to usage in a power plant again. The result is in picture 4. It is nuclear fuel - a compact, inert, insoluble solid

1 2 3 4

http://en.wikipedia.org/wiki/Nuclear_fuel_cycle

The diagram of the typical stages of the nuclear fuel cycle may be presented as the following:

http://ocw.cupide.org/OcwWeb/Nuclear-Engineering/22-351Systems-Analysis-of-the-Nuclear-Fuel-Cycle

A nuclear reactor produces and controls the release of energy from splitting the atoms of certain elements. In a nuclear power reactor, the energy released is used as heat to make steam to generate electricity. (In a research reactor the main purpose is to utilise the actual neutrons produced in the core. In most naval reactors, steam drives a turbine directly for propulsion.)

The principles for using nuclear power to produce electricity are the same for most types of reactor. The energy released from continuous fission of the atoms of the fuel is harnessed as heat in either a gas or water, and is used to produce steam. The steam is used to drive the turbines which produce electricity (as in most fossil fuel plants).

There are several components common to most types of reactors:

Fuel. Usually pellets of uranium oxide (UO₂) arranged in tubes to form fuel rods. The rods are arranged into fuel assemblies in the reactor core.

Moderator. This is material which slows down the neutrons released from fission so that they cause more fission. It is usually water, but may be heavy water or graphite.

Control rods. These are made with neutron-absorbing material such as cadmium, hafnium or boron, and are inserted or withdrawn from the core to control the rate of reaction, or to halt it. (Secondary shutdown systems involve adding other neutron absorbers, usually as a fluid, to the system.)

Coolant. A liquid or gas circulating through the core so as to transfer the heat from it. . In light water reactors the water moderator functions also as primary coolant. Except in BWRs, there is secondary coolant is what makes the steam. (see also later section on primary coolant characteristics and Appendix re water use for secondary cooling.)

Pressure vessel or pressure tubes. Usually a robust steel vessel containing the reactor core and moderator/coolant, but it may be a series of tubes holding the fuel and conveying the coolant through the moderator.

Steam generator. Part of the cooling system where the heat from the reactor is used to make steam for the turbine.

Containment. The structure around the reactor core which is designed to protect it from outside intrusion and to protect those outside from the effects of radiation in case of any malfunction inside. It is typically a metre-thick concrete and steel structure. (www.uic.com.au)

The structure of a nuclear power plant in many aspects resembles to that of a conventional thermal power station, since in both cases the heat produced in the boiler (or reactor) is transported by some coolant and used to generate steam. The steam then goes to the blades of a turbine and by rotating it, the connected generator will produce electric energy. The steam goes to the condenser, where it condenses, i.e. becomes liquid again. The cooled down water afterwards gets back to the boiler or reactor, or in the case of PWRs to the steam generator.

“The great difference between a conventional and a nuclear power plant is how heat is produced. In a fossile plant, oil, gas or coal is fired in the boiler, which means that the chemical energy of the fuel is converted into heat. In a nuclear power plant, however, energy that comes from fission reactions is utilized”. (www.npp.hu/mukodes/tipusok)

Pressurised Water Reactor (PWR)

This is the most common type, with over 230 in use for power generation and a further several hundred in naval propulsion. The design originated as a submarine power plant. It uses ordinary water as both coolant and moderator. The design is distinguished by having a primary cooling circuit which flows through the core of the reactor under very high pressure, and a secondary circuit in which steam is generated to drive the turbine.

A PWR has fuel assemblies of 200-300 rods each, arranged vertically in the core, and a large reactor would have about 150-250 fuel assemblies with 80-100 tonnes of uranium.

Water in the reactor core reaches about 325 C, hence it must be kept under about 150 times atmospheric pressure to prevent it boiling. Pressure is maintained by steam in a pressuriser (see diagram). In the primary cooling circuit the water is also the moderator, and if any of it turned to steam the fission reaction would slow down. This negative feedback effect is one of the safety features of the type. The secondary shutdown system involves adding boron to the primary circuit.

The secondary circuit is under less pressure and the water here boils in the heat exchangers which are thus steam generators. The steam drives the turbine to produce electricity, and is then condensed and returned to the heat exchangers in contact with the primary circuit. (www.uic.com.au)

Boiling Water Reactor (BWR).

This design has many similarities to the PWR, except that there is only a single circuit in which the water is at lower pressure (about 75 times atmospheric pressure) so that it boils in the core at about 285C. The reactor is designed to operate with 12-15% of the water in the top part of the core as steam, and hence with less moderating effect and thus efficiency there.

The steam passes through drier plates (steam separators) above the core and then directly to the turbines, which are thus part of the reactor circuit. Since the water around the core of a reactor is always contaminated with traces of radionuclides, it means that the turbine must be shielded and radiological protection provided during maintenance. The cost of this tends to balance the savings due to the simpler design. Most of the radioactivity in the water is very short-lived, so the turbine hall can be entered soon after the reactor is shut down. A BWR fuel assembly comprises 90-100 fuel rods, and there are up to 750 assemblies in a reactor core, holding up to 140 tonnes of uranium. The secondary control system involves restricting water flow through the core so that steam in the top part means moderation is reduced. (www.uic.com.au)

Pressurised Heavy Water Reactor (PHWR or CANDU).

The CANDU reactor design has been developed since the 1950s in Canada. It uses natural uranium (0.7% U-235) oxide as fuel, hence needs a more efficient moderator, in this case heavy water (D₂O). The moderator is in a large tank called a calandria, penetrated by several hundred horizontal pressure tubes which form channels for the fuel, cooled by a flow of heavy water under high pressure in the primary cooling circuit, reaching 290?C. As in the PWR, the primary coolant generates steam in a secondary circuit to drive the turbines. The pressure tube design means that the reactor can be refuelled progressively without shutting down, by isolating individual pressure tubes from the cooling circuit. A CANDU fuel assembly consists of a bundle of 37 half metre long fuel rods (ceramic fuel pellets in zircaloy tubes) plus a support structure, with 12 bundles lying end to end in a fuel channel. Control rods penetrate the calandria vertically, and a secondary shutdown system involves adding gadolinium to the moderator. The heavy water moderator circulating through the body of the calandria vessel also yields some heat/(www.uic.com.au)

Advanced Gas-cooled Reactor (AGR)

These are the second generation of British gas-cooled reactors, using graphite moderator and carbon dioxide as coolant. The fuel is uranium oxide pellets, enriched to 2.5-3.5%, in stainless steel tubes. The carbon dioxide circulates through the core, reaching 650C and then past steam generator tubes outside it, but still inside the concrete and steel pressure vessel. Control rods penetrate the moderator and a secondary shutdown system involves injecting nitrogen to the coolant. The AGR was developed from the Magnox reactor, also graphite moderated and CO₂ cooled, and a number of these are still operating in UK. They use natural uranium fuel in metal form. (www.uic.com.au)

Light water graphite-moderated reactor (RBMK).

This is a Soviet design, developed from plutonium production reactors. It employs long (7 metre) vertical pressure tubes running through graphite moderator, and is cooled by water, which is allowed to boil in the core at 290°C, much as in a BWR. Fuel is low-enriched uranium oxide made up into fuel assemblies 3.5 metres long. With moderation largely due to the fixed graphite, excess boiling simply reduces the cooling and neutron absorbtion without inhibiting the fission reaction, and a positive feedback problem can arise. (www.uic.com.au)

Advanced reactors

Several generations of reactors are commonly distinguished. Generation I reactors were developed in 1950-60s and very few are still running today. They mostly used natural uranium fuel and used graphite as moderator. Generation II reactors are typified by the present US fleet and most in operation elsewhere. They typically use enriched uranium fuel and are mostly cooled and moderated by water. Generation III are the Advanced Reactors, the first few of which are in operation in Japan and others are under construction and ready to be ordered. They are developments of the second generation with enhanced safety.

Generation IV designs are still on the drawing board and will not be operational before 2020 at the earliest, probably later. They will tend to have closed fuel cycles and burn the long-lived actinides now forming part of spent fuel, so that fission products are the only high-level waste. Many will be fast neutron reactors.

More than a dozen (Generation III) advanced reactor designs are in various stages of development. Some are evolutionary from the PWR, BWR and CANDU designs above, some are more radical departures. The former include the Advanced Boiling Water Reactor, a few of which are now operating with others under construction. The best-known radical new design is the Pebble Bed Modular Reactor, using helium as coolant, at very high temperature, to drive a turbine directly.

Considering the closed fuel cycle, Generation 1-3 reactors recycle plutonium (and possibly uranium), while Generation IV are expected to have full actinide recycle. (www.uic.com.au)

The military implications of civilian nuclear programs illustrate the reason why our choices in the nuclear energy field are not simple ones between good and evil. Nowdays there are some countries that have the scientific and economic capabilities to convert from civilian to military use. They are: France, China, the United States and Russia. We can make such as conclusions because this countries produce most of nuclear weapons in the world.

France is estimated to have approximately 350 nuclear warheads. France reserves the right to use nuclear weapons first in a conflict. It has reaffirmed a 1995 pledge not to use nuclear weapons against non-nuclear-weapon states-parties to the NPT. At the same time, French President Jacques Chirac suggested in January 2006 that nuclear weapons would be an option for responding to states that conduct “terrorist” or any type of weapon of mass destruction attack against France. Chirac announced in February 1996 that France no longer produced fissile material, highly enriched uranium (HEU) and plutonium, for weapons purposes. He also vowed that France would dismantle its fissile material production facilities for arms. France is estimated to have approximately 30 metric tons of HEU and five metric tons of plutonium for weapons purposes. (www.armscontrol.org/factsheets/franceprofile)

China maintains strict secrecy on the size of its nuclear arsenal, but independent estimates generally range between 100 and 200 warheads. In an April 2004 statement, China claimed that it “possesses the smallest nuclear arsenal” of the five recognized NPT nuclear-weapon states.  China is the sole nuclear-weapon state to declare publicly that it will not be the first to use nuclear weapons. Beijing has emphasized that this vow stands “at any time or under any circumstances.”Although China has not publicly declared a halt to the production of fissile material, highly enriched uranium (HEU) and plutonium, general speculation is that Beijing has stopped. One independent estimate calculates that China has accumulated as much as 25 metric tons of HEU and six metric tons of plutonium for weapons. (www.armscontrol.org/factsheets/chinaprofile)

The U.S. nuclear stockpile consists of approximately 10,000 strategic and tactical warheads. This stockpile includes warheads deployed and those stored in reserve, but it does not include retired warheads that are awaiting dismantlement. The United States reserves the right to use nuclear weapons first in a conflict. It has pledged not to use nuclear weapons against non-nuclear-weapon states-parties in good standing under the NPT unless they attack the United States in league with a state possessing nuclear arms. Top U.S. officials, however, have repeatedly hinted that Washington might respond with nuclear arms to a chemical or biological weapons attack, regardless of whether the attacker has nuclear weapons. In its secret September 2002 National Security Presidential Directive-17, the George W. Bush administration stated explicitly that U.S. retaliation options for any type of weapon of mass destruction attack against the United States includes nuclear weapons.  The United States is the only country to have used nuclear weapons against another country, dropping in August 1945 two bombs (one apiece) against the Japanese cities of Hiroshima and Nagasaki.  The United States has publicly declared that it no longer produces fissile material, highly enriched uranium (HEU) and plutonium, for weapons purposes. The United States halted the production of HEU for weapons in 1964 and ceased plutonium reprocessing for weapons in 1992. Current U.S. fissile stockpiles for weapons total about 47 declared metric tons of plutonium and 250 declared metric tons of HEU. Under an agreement finalized in 2000 with Russia, the United States is committed to disposing of 34 metric tons of excess plutonium, but the project has been delayed. (www.armscontrol.org/factsheets/unitedstatesprofile)

Estimates of Russia’s total nuclear forces, including tactical or battlefield nuclear weapons, vary greatly. It is generally estimated that Russia also may have up to 3,000 tactical nuclear warheads in service. In addition, Russia may have as many as 8,000 to 10,000 nuclear warheads in reserve. In 1993, Russia abandoned the Soviet Union’s previous pledge not to use nuclear weapons first. Moscow has reiterated past pledges not to use nuclear weapons against states that do not possess them, but it also has warned that it might use nuclear weapons if other responses failed to “repulse armed aggression.” Russia has publicly declared that it no longer produces fissile material, highly enriched uranium (HEU) and plutonium, for weapons purposes. The Kremlin announced a halt to HEU production for weapons in 1989 and the cessation of plutonium production for weapons in 1994. As with Russia’s warhead stockpile, there is a great deal of uncertainty about its holdings of fissile material. One independent 2007 report estimates that Russia possibly has 640 metric tons of HEU, which could vary by as much as 300 metric tons, and 120 to 170 metric tons of plutonium stockpiled for weapons. With the United States, Russia is implementing a program to downblend 500 metric tons of Russian excess HEU into reactor fuel unsuitable for bombs. That project is supposed to be completed in 2013. The two countries, however, have yet to begin disposing of 68 metric tons of excess plutonium (34 tons apiece) under an agreement finalized in 2000. (www.armscontrol.org/factsheets/russiaprofile)

Nowdays nuclear energy is a very perspective way of energy development. That’s why many people work in this sphere: for example in Russia there’re about 350.000 such as workers. We all now are connected to a huge network of people, electric lines, and generating equipment. Power plant operators control the machinery that generates electricity. Power plant distributors and dispatchers control the flow of electricity from the power plant, over a network of transmission lines, to industrial plants and substations, and, finally, over distribution lines to residential users.

Power plant operators control and monitor boilers, turbines, generators, and auxiliary equipment in power-generating plants. Operators distribute power demands among generators, combine the current from several generators, and monitor instruments to maintain voltage and regulate electricity flows from the plant. When power requirements change, these workers start or stop generators and connect or disconnect them from circuits. They often use computers to keep records of switching operations and loads on generators, lines, and transformers. Operators also may use computers to prepare reports of unusual incidents, malfunctioning equipment, or maintenance performed during their shift.

Operators in plants with automated control systems work mainly in a central control room and usually are called control room operators or control room operator trainees or assistants. In older plants, the controls for the equipment are not centralized; switchboard operators control the flow of electricity from a central point, while auxiliary equipment operators work throughout the plant, operating and monitoring valves, switches, and gauges.

In nuclear power plants, most operators start working as equipment operators or auxiliary operators. They help the more senior workers with equipment maintenance and operation while learning the basics of plant operation. With experience and training they may be licensed by the Nuclear Regulatory Commission as reactor operators and authorized to control equipment that affects the power of the reactor in a nuclear power plant. Senior reactor operators supervise the operation of all controls in the control room. At least one senior operator must be on duty during each shift to act as the plant supervisor.

Power distributors and dispatchers, also called load dispatchers or systems operators, control the flow of electricity through transmission lines to industrial plants and substations that supply residential needs for electricity. They monitor and operate current converters, voltage transformers, and circuit breakers. Dispatchers also monitor other distribution equipment and record readings at a pilot board—a map of the transmission grid system showing the status of transmission circuits and connections with substations and industrial plants.

Dispatchers also anticipate power needs, such as those caused by changes in the weather. They call control room operators to start or stop boilers and generators, in order to bring production into balance with needs. Dispatchers handle emergencies such as transformer or transmission line failures and route current around affected areas. In substations, they also operate and monitor equipment that increases or decreases voltage, and they operate switchboard levers to control the flow of electricity in and out of the substations. (www.bls.gov/home.htm)

In Benchmark I, I tried to examine the objectives from the point of view of different domains to gain a comprehensive understanding and comparison of conventional energy, and nuclear energy in different countries in the world. I also began to define issues related to nuclear proliferation, and nuclear terrorism.

In Benchmark II, I will try to investigate the spread, proliferation, of nuclear energy in the world today, and some of the issues involved with the use and spread of nuclear energy.

“We view security as a multidimensional concept. It is an area that requires a carefully considered and complex approach. Based on this position, Russia is firmly committed to expanding cooperation on global energy security within the framework of the Eurasian Economic Community. One of the priorities in this area is to develop cooperation in the peaceful use of nuclear energy,” said President Vladimir Putin in his Statement on the Peaceful Use of Nuclear Energy at the Eurasian Economic Community summit, Konstantin palace, St Petersburg http://www.mid.ru/

I agree, the planet Earth is in our hands. We must think about the peaceful use of nuclear energy first of all.

http://www.spiritofmaat.ru/messagesofhope/index.html

BIBLIOGRAPHY

1. Longman Dictionary of American English, Third edition 2002

2. Longman Pearson Exam Coach Dictionary,2005

3. http://en.wikipedia.org

4. http://en.wikipedia.org/wiki/Nuclear_terrorism

5. http://en.wiktionary.org/wiki/proliferation

6. http://en.wikipedia.org/wiki/Nuclear_power_reactor

7. www.ccs.neu.edu/home/gene/peakoil

8. www.cfr.org

9. www.eia.doe.gov/kids/energyfacts/sources/non-renewable/oil

10. www.nationaltrust.org.uk.

11. www.library.thinkquest.org/21794/energysources.

12. www.eia.doe.gov/emeu/cabs.

13. www.encarta.msn.com/encyclopedia_761561465 .

14. www.nationsencyclopedia.com/Europe/France.

15. www.greenpeace.org/usa/photosvideos/photos/doel-steam-generator .

16. http://en.wikipedia.org/wiki/Nuclear_fuel_cycle .

17.http://ocw.cupide.org/OcwWeb/Nuclear-Engineering/22-351Systems-Analysis-of-the-Nuclear-Fuel-Cycle.

18. www.npp.hu/mukodes/tipusok.

19. www.uic.com.au.

20 www.armscontrol.org/factsheets/franceprofile.

21. www.armscontrol.org/factsheets/unitedstatesprofile.

22. www.armscontrol.org/factsheets/russiaprofile.

23. www.bls.gov/home.htm.

24. www.britannica.com.

25. http://www.mid.ru/

Bibliography I also used while working on Benchmark I:

1. “Nuclear Power: Current Status, Plans for the Near Future, and Proliferation Implications” (Cristina Chuen, CNS Newly Independent States Nonproliferation Program (NISNP) director)
original Powerpoint file.

2. "Nuclear Power Technologies" (Speaker: Craig Smith, Naval Post Graduate School/Lawrence Livermore National Laboratory)
original Powerpoint file.

3. "Nuclear Terrorism" (Cristina Chuen, CNS Newly Independent States Nonproliferation Program (NISNP) director)
original Powerpoint file.

4. History of Nuclear Energy/Risks and Benefits including Past Incidents (Sonja Schmid, CNS Post Doctoral Fellow)
original Powerpoint file.

5. V.P. Maksakovsky, Geography, text-book for secondary schools, Moscow, Prosvesheniye, 2007.

6. G.F. Bystritsky, Foundations of Energy, Text-book for schools, Moscow, Infra-M,2007.

7. l.A. Melentiev, Sketches on the history of the native power engineering,Moscow, Nauka,1987.