Energy From Nuclear Power

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Energy From Nuclear Power

• APES CH 13

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• Nuclear Energy in Perspective
• We are currently in the midst of an energy
  crunch.
• Fossil fuels will not last forever.
• Nuclear power does not contribute to global
  warming.
• 31 nations now have nuclear power plants in place
  or under construction
• Some of these countries rely on nuclear power for
  most of their electricity
• The history of Nuclear power goes back to the
  years right after WW II, it was an effort to use
  the technology developed for war as a means of
  producing energy for peace time.

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• GE and Westinghouse built power plants paid for
  by utility companies
• They received assurances from the federal
  government that they would not be liable for
  legal liabilities.
• Department of Energy set safety standards for
  operations and maintenance.
• In 1970, there were 53 plants operating in the
  US, producing 9 of the electricity. There were
  another 170 plants either planned or being built.
• Since 1975, utilities stopped ordering nuclear
  plants, numerous existing orders were canceled.

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• The Shorham Plant on Long Island was built,
  licensed at a cost of 5.5 billion and dismantled
  after generating electricity for only 32 hours.
• The state determined that there was no way to
  evacuate the people in the event of an accident.
• Rancho Seco Plant near Sacramento was also shut
  down.
• 28 separate reactors have been shut down to date.
• At the end of 2003, 104 nuclear power plants were
  operating in the US.
• Nuclear Power Plants are not forever, as plants
  are decommissioned, estimates are that 27 will
  be out of commission by 2020.

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• The world ha a total of 441 operating nuclear
  plants with 32 under construction.
• This generates about 17 of the worlds
  electricity.
• France generates 78 of its electricity with
  Nuclear power and plans to go to more than 80.
• Japan has few resources, and generates
  electricity with 55 nuclear reactors. 35 of
  their electricity needs.
• How does Nuclear Power Work?
• Nuclear energy involves changes at the atomic
  level.
• In fission, a large atom of one element is split
  to produce 2 smaller atoms of different elements.
• In fusion, 2 small atoms combine to form a larger
  atom of a different element

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• In fusion and fission,
• The mass of the product is lass than the mass of
  the starting material.
• The lost mass is converted to energy in
  accordance with the equation Emc2.
• Fuel for Nuclear Power Plants
• All current power plants use U-235 as a fuel.
• U occurs naturally in two forms (isotopes)
• Uranium 238
• Uranium 235
• These differ by the number of neutrons in the
  nucleus of the atom. The number of protons and
  electrons remain the same.
• The difference is that U-235 will readily undergo
  fission, U-238 will not.

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• So what causes fission to occur?
• A neutron hitting the nucleus at just the right
  speed causes an atom of U-235 to undergo fission.
  The neutron creates U-236 which is highly
  unstable and will spontaneously decay into two
  lighter elements.
• The fission reaction gives off more neutrons and
  releases a great deal of energy.
• More neutrons and more energy is released. This
  is called a chain reaction, like a domino effect.

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• Nuclear Fuel
• U is mined and purified into uranium dioxide
  (UO2).
• U must be enriched. This involves separating
  U-235 from U-238. This is done with a special
  centrifuge. This technology is what keeps less
  developed countries from advancing their nuclear
  capabilities.
• Nuclear Bomb
• When U-235 is highly enriched, a small amount of
  U-235 can generate a chain reaction
  spontaneously.
• In a bomb, 2 small amounts of almost U-235 are
  forced together so that a critical mass is
  reached. This allows all the mass to undergo
  fission in a fraction of a second, releasing all
  the energy in one huge explosion

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• The Nuclear Reactor
• This is designed to sustain a chain reaction but
  not allow it to amplify into a nuclear explosion.
• In the reactor, there is only 4 U-235 and 96
  U-238.
• In the process of enrichment, some U -238 absorbs
  neutrons converting them into Pu-239. This also
  undergoes fission when hit by another neutron.
• Actually, about 1/3 of the energy from a reactor
  comes from Pu fission.

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• The moderator
• A chain reaction can be achieved only if a
  sufficient mass of enriched uranium is arranged
  in a suitable geometric pattern and is surrounded
  by a material known as a moderator.
• The moderator slows down neutrons so that they
  travel at the right speed to induce fission
• In the process, the moderator gains heat.
• In the US, the moderator is nearly pure water.
• Other reactors use graphite or heavy water
  (deuterium oxide).
• Fuel Rods
• To achieve the geometric pattern the uranium fuel
  is made into pellets which are then loaded into
  long metal tubes.
• The long tubes are called fuel rods
• Many fuel rods are placed close together inside a
  reactor vessel which holds the water.
• The water acts as a moderator and a heat exchange
  fluid.

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Nuclear Reactor Components
Fuel rod assembly
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• Fuel rod assembly including control rods
• Diagram of a nuclear fuel assembly revealing the
  complexity of the system to be considered over
  the long term. Approximately 4 m long and 9.5 mm
  in section, each of the 264 rods is secured in a
  space apart by grids to make up an assembly the
  rod is made up of Zircaloy (alloy based on metal
  zirconium) cladding 580 mm thick into which 265
  pellets of uranium dioxide UO2 are loaded.

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The control rod assembly
The control rod moves inside the fuel element to
control nuclear fission. During operation it is
lifted to compensate the burn-up of the nuclear
fuel.
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• Over time, the daughter products accumulate in
  the fuel rods and slow down the fission rate.
• This is now spent fuel and is removed
• Control Rods
• These consist of neutron absorbing material and
  are inserted between the fuel elements.
• The chain reaction is started and controlled by
  inserting and withdrawing the control rods.
• As the control rods are removed and a chain
  reaction begins, the fuel rods and the moderator
  become intensely hot,

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• The Nuclear Power Plant
• Heat from the reactor is used to boil water to
  provide steam to drive a conventional turbine.
• In the US, the moderator water is heated to 600
  C. It is circulated through the reactor but does
  not boil as it is under very high pressure.
• This superheated water is circulated through a
  heat exchanger, boiling other unpressurized water
  that flows past the heat exchanger tubes this
  produces the steam that drives the turbines.

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• LOCA
• This stands for loss of coolant accident.
• The US systems are what is called a double loop
  design. It has the drawback in that this design
  is subject to LOCA.
• This can result in the cores overheating. This
  could cause fission to cease since the moderator
  would no longer be present.
• It would still cause the fuel core to overheat.
  This would release the materials in the core -
  meltdown.
• then the molten material falling into the
  remaining water could cause a steam explosion.

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• To prevent this, there are backup cooling systems
  to keep the reactor immersed in water. Also, the
  entire assembly is housed in a thick concrete
  containment building.
• Comparing Nuclear Power with Coal Power.
• Right now, no more nuclear plants are being
  built. We have no choice but to replace nuclear
  plants with coal burning plants.
• Even though there are concerns about nuclear
  power, there are some good environmental reasons
  to pursue nuclear power.

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• In one year..at a 1000 megawatt nuclear power
  plant compared with a 1000 megawatt coal plant
• Fuel -
• coal plant
• consumes 2-3 million tons of coal
• this is obtained by strip mining, which causes
  environmental destruction and acid leaching
• also a cost in the form of accidental deaths and
  health concerns
• 7 tons of CO2
• Nuclear power plant
• requires 30 tons of U obtained from mining 75,000
  tons of ore
• less harm to humans and the environment
• the fission of 1 lb of U releases the energy
  equivalent of 50 tons of coal.
• 60 tons of U is sufficient to run the nuclear
  plant for 2 years
• no CO2

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• Radioactivity
• a coal plant releases 100 times more
  radioactivity than a nuclear power plant
• the coal plant produces 600,000 tons of ash
  requiring land disposal
• wastes
• the nuclear plant produces 250 tons of highly
  radioactive wastes requiring safe storage and
  ultimate safe disposal. (unsolved problem).
• Accidents -
• worst case accident could cause death to workers
  and fire
• accidents in a nuclear plant could be as small as
  a small emission of radioactive gases or a
  catastrophic release of radioactive material with
  many dead, long-lasting environmental damage and
  cancers to humans and animals

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• 13.3 The Hazards and Costs of Nuclear Power
  Facilities
• radioactive emissions
• direct products of the fission reaction are
  unstable. These are called radioisotopes
• they become stable by radioactive decay
• this process emits alpha particles, beta
  particle, neutron and high energy radiation.
• Radioactivity is measured in curies. One gram of
  pure radium-226 gives off 1 curie per second
• the particles and radiation are collectively
  referred to as radioactive emissions and are the
  wastes of nuclear power

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• biological effects
• radioactive emissions can penetrate tissue.
  Their ability to do damage is measured in units
  called sieverts
• the emissions leave no mark, nor are they felt.
  They can dislodge electrons from molecules or
  atoms that they strike. This produces an ion.
• These emissions are therefore called ionizing
  radiation.
• The process of ionization can create molecules
  that are no longer able to function in their
  normal capacity.
• In high doses (over 1 sievert is considered high)
  radiation can cause enough damage to prevent cell
  division.
• This can cause radiation sickness, preventing
  normal repair of blood, skin and other tissues.
  Death can occur in a few days or months.

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• Low dose
• radiation might damage DNA. Cells with damaged
  DNA may then begin growing out of control.
  (malignant tumor or leukemia).
• If the damaged DNA is in an egg or a sperm, the
  result might be birth defects
• the redults might be unseen until many years
  after the event.
• Exposure
• health effects are directly related to the level
  of exposure
• between 100 and 500 millisieverts results in an
  increase in the risk of developing cancer.
• Many scientists believe that no dose is without
  some harm.
• Some believe that there is a mechanism to repair
  some damaged DNA.

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• Federal standards are set at 1.7 mSv/year as the
  maximum exposure permitted for the general
  population except for medical X-rays.
• Sources of radiation -
• People are exposed to radiation naturally from U
  and Rn in Earths crust. We are also exposed to
  cosmic rays from outer space.
• Medical and ental X-rays are the largest source
  of human induced exposure.
• The average person in the Us receives about 3.6
  mSv/year.
• So, the question is, is radiation from nuclear
  power likely to significantly raise radiation
  levels and elevate the risk of developing cancer?
• During normal operation, the fission products
  remain within the fuel elements. No routine
  discharges of radioactive materials occur.
• The real problems arise from the storage and
  disposal of radioactive wastes and the potential
  for accidents.

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• Radioactive Wastes
• radioactive decay occurs over a time period known
  as a half life
• the half life is the time it takes for half of
  the starting amount of a given isotope to decay.
  During the next half life, half as much will
  again decay.
• Each radioactive isotope has a characteristic
  half life.
• This can be as long as a fraction of a second to
  many thousands of years.
• The main culprit is U-239, which has a half life
  of 24,000 years.
• In France and Great Britain, P-239 is recovered
  and recycled as nuclear fuel in an operation
  called reprocessing.

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• Disposal of Radioactive Wastes
• In 10 years most radioactive waste lose more than
  97 of their radioactivity.
• Short term containment - waste is stored in tanks
  and casks in deep swimming pools. The water in
  the tanks absorbs waste heat. The waste storage
  capacity reached 50 in 2004 and will be at 100
  by 2015.
• After this, the waste can be stored in a dry
  storage facility and air cooled for interim
  storage until long term storage becomes
  available.
• The waste is accumulating at a rate of 10,000
  tons per year and is all stored on site at
  nuclear reactors.

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• Military radioactive wastes
• some of the worst failures in handling wastes
  have occurred at ,military facilities in the S
  and in the Soviet Union.
• Some of these releases have been deliberate.
• For at least 20 years nuclear wastes were
  discharged into the Techa River and then into
  Lake Karachay.
• At least 1000 cases of leukemia have been kinked
  to this radiation contamination.
• Today, standing on the hore of Lake Karachay for
  one hour ill cause radiation posioning and death
  within a week.
• In 1967 the lake dried up and the winds blew the
  radioactive sediments all over.
• This lake is considered the most polluted spot on
  Earth.

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• Yucca Mountain
• the US has decided that the best plan to deal
  with high level nuclear waste is to bury it.
• No rock formation can be guarantied to remain
  stable and dry for tens of thousands of years.
• If earthquake activity or even groundwater
  leaching occurs, the radioactive wastes could
  escape into the environment and contaminate
  water, soil, or air.
• Yucca mountain has been selected to be the
  nations civilian nuclear waste disposal site.
• Nevadans have fought this selection
• there is a NIMBY attitude everywhere.

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• George W Bush voided a veto by Nevada Governor
  Kenny Guinn, w3ho was attempting to block further
  development on the YM site.
• The site could be ready to accept wastes by
  2010.in the meantime, there is an underground
  storage facility in New Mexico from nuclear
  weapons facilities since 1999.

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• Nuclear Power Accidents
• Three Mile Island
• partial meltdown as a result of s series of human
  and equipment failures and a flawed design
• steam generator shut down automatically because
  of a lack of power in its feedwater pumps
• a valve on top of the generator opened in
  response to the buildup of pressure.
• The valve remained stuck in the open position and
  drained coolant water from the reactor vessel.
• There were no sensors to indicate that this valve
  was opened.Operators shut down the emergency
  cooling system at one point and shut down the
  pumps in the reactor vessel (compounded the
  problem).
• The core was uncovered for a time and suffered a
  partial meltdown.

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• 10 million curies of radioactive gas were
  released into the atmosphere.
• The reactor damage was bad. The cleanup I
  proving to be as costly as building a new power
  plant.
• The company has never admitted any radiation
  caused illnesses

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• Chernobyl April 26, 1986
• A test for standby diesel generators.
• Engineers disabled the power plants safety
  systems withdrew the control rods, shut off the
  flow of steam to the generators and decreased the
  flow of coolant water in the reactor.
• They did not allow for the radioactive heat
  energy generated by the fuel core, and , lacking
  coolant, the reactor began to heat up.
• The steam that was produced could not escape and
  boosted the energy production of the reaction
• the engineers inserted the control rods.
• The control rods acted as moderators
• the neutrons were still speedy enough to trigger
  more fission
• steam explosions blew off the top of the reactor
  and the reactor melted down.

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• 50 tons of dust and debris bearing 100-200
  million curies were spread over thousands of
  square miles
• this was 100 times the radiation fallout from the
  bombs dropped on Hiroshima and Nagasaki.
• 135,000 people were evacuated
• the reactor was eventually sealed in steel and
  concrete.
• There is a 1000 square mile exclusion zone around
  the reactor site.
• 2 engineers were directly killed
• 29 emergency personnel died within a few months.
• There has been a great increase in thyroid cancer
  due to the short lived I-131 being released.
• The authorities waited a week to distribute I
  pills to those effected.
• More than 4000 Ukrainians who participated in the
  cleanup died, 70,000 have become disabled

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• It is expected that between 140,000 - 475,000
  cancers will be attributed to the accident world
  wide
• Can it happen here?
• The US designed power plants use water as a
  moderator, not graphite.
• LWRs (light water reactors) are incapable of
  developing a power surge more than twice their
  normal power
• LWRs have better back up systems to prevent the
  core from overheating
• the reactors are housed in containment buildings
  designed to withstand explosions. (Chernobyl had
  no containment building)
• An LWE could totally lose coolant, although this
  has never happened, Three Mile Island was a close
  call.

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• New Generations of Reactors -
• more safety features
• likely to be built within the next 20 years
• smaller reactors
• cheaper to build
• Terrorism
• this is a problem
• Economic problems-
• life of a nuclear plant shorter than previously
  thought
• due to embrittlement - metals become brittle and
  more subject to stress

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• Corosion - hot pressurized water cause cracks to
  develop over time
• Decommissioning - closing down a reactor is
  costly. The materials are now radioactive.
• Old sites need to be turned into something.
• Breeder reactors
• a breeder reactor converts U-238 to P-239 which
  can be used a a nuclear fuel.. The breeder may
  actually produce more fuel than it consumes.
  Most of the U in the reactor is U-238 an is not
  fissionable so this increases nuclear fuel
  reserves more than 100-fold.
• These reactors still have all the problems and
  hazards of the old style reactors.

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• Fusion
• This is what happens on the Sun
• two H atoms fuse to produce a He atom, releasing
  energy.
• Source of H would be water.
• He is an inert, nonpollution, nonradioactive gas.
• At the present state, fusion I still an energy
  user rather than a producer due to the high
  temperatures required to get H atoms to fuse.
• The joke is that fusion is the energy source of
  the future and always will be.

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• In nuclear fusion, you get energy when two atoms
  join together to form one. In a fusion reactor,
  hydrogen atoms come together to form helium
  atoms, neutrons and vast amounts of energy. It's
  the same type of reaction that powers hydrogen
  bombs and the sun. This would be a cleaner,
  safer, more efficient and more abundant source of
  power than nuclear fission.
• There are several types of fusion reactions. Most
  involve the isotopes of hydrogen called deuterium
  and tritium

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• Proton-proton chain - This sequence is the
  predominant fusion reaction scheme used by stars
  such as the sun.
• Two pairs of protons form to make two deuterium
  atoms.
• Each deuterium atom combines with a proton to
  form a helium-3 atom.
• Two helium-3 atoms combine to form beryllium-6,
  which is unstable.
• Beryllium-6 decays into two helium-4 atoms. These
  reactions produce high energy particles (protons,
  electrons, neutrinos, positrons) and radiation
  (light, gamma rays)

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• Deuterium-deuterium reactions - Two deuterium
  atoms combine to form a helium-3 atom and a
  neutron.
• Deuterium-tritium reactions - One atom of
  deuterium and one atom of tritium combine to form
  a helium-4 atom and a neutron. Most of the energy
  released is in the form of the high-energy
  neutron.
• Conceptually, harnessing nuclear fusion in a
  reactor is a no-brainer. But it has been
  extremely difficult for scientists to come up
  with a controllable, non-destructive way of doing
  it. To understand why, we need to look at the
  necessary conditions for nuclear fusion.

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• Conditions for Nuclear Fusion
• When hydrogen atoms fuse, the nuclei must come
  together. However, the protons in each nucleus
  will tend to repel each other because they have
  the same charge (positive). If you've ever tried
  to place two magnets together and felt them push
  apart from each other, you've experienced this
  principle first-hand. To achieve fusion, you need
  to create special conditions to overcome this
  tendency. Here are the conditions that make
  fusion possible
• High temperature - The high temperature gives the
  hydrogen atoms enough energy to overcome the
  electrical repulsion between the protons.
• Fusion requires temperatures about 100 million
  Kelvin (approximately six times hotter than the
  sun's core).
• At these temperatures, hydrogen is a plasma, not
  a gas. Plasma is a high-energy state of matter in
  which all the electrons are stripped from atoms
  and move freely about.
• The sun achieves these temperatures by its large
  mass and the force of gravity compressing this
  mass in the core. We must use energy from
  microwaves, lasers and ion particles to achieve
  these temperatures.

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• High pressure - Pressure squeezes the hydrogen
  atoms together. They must be within 1x10-15
  meters of each other to fuse.
• The sun uses its mass and the force of gravity to
  squeeze hydrogen atoms together in its core.
• We must squeeze hydrogen atoms together by using
  intense magnetic fields, powerful lasers or ion
  beams.
• With current technology, we can only achieve the
  temperatures and pressures necessary to make
  deuterium-tritium fusion possible.
  Deuterium-deuterium fusion requires higher
  temperatures that may be possible in the future.
  Ultimately, deuterium-deuterium fusion will be
  better because it is easier to extract deuterium
  from seawater than to make tritium from lithium.
  Also, deuterium is not radioactive, and
  deuterium-deuterium reactions will yield more
  energy.

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• Fusion Reactors Magnetic Confinement
• Tokamak
• "Tokamak" is a Russian acronym for "toroidal
  chamber with axial magnetic field."There are two
  ways to achieve the temperatures and pressures
  necessary for hydrogen fusion to take place
• Magnetic confinement uses magnetic and electric
  fields to heat and squeeze the hydrogen plasma.
  The ITER project in France is using this method.
• Inertial confinement uses laser beams or ion
  beams to squeeze and heat the hydrogen plasma.
  Scientists are studying this experimental
  approach at the National Ignition Facility of
  Lawrence Livermore Laboratory in the United
  States.
• Let's look at magnetic confinement first. Here's
  how it would work

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• Microwaves, electricity and neutral particle
  beams from accelerators heat a stream of hydrogen
  gas. This heating turns the gas into plasma. This
  plasma gets squeezed by super-conducting magnets,
  thereby allowing fusion to occur. The most
  efficient shape for the magnetically confined
  plasma is a donut shape (toroid).

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• A reactor of this shape is called a tokamak. The
  ITER tokamak will be a self-contained reactor
  whose parts are in various cassettes. These
  cassettes can be easily inserted and removed
  without having to tear down the entire reactor
  for maintenance. The tokamak will have a plasma
  toroid with a 2-meter inner radius and a
  6.2-meter outer radius.
• Let's take a closer look at the ITER fusion
  reactor to see how magnetic confinement works.

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• Vacuum vessel - holds the plasma and keeps the
  reaction chamber in a vacuum
• Neutral beam injector (ion cyclotron system) -
  injects particle beams from the accelerator into
  the plasma to help heat the plasma to critical
  temperature
• Magnetic field coils (poloidal, toroidal) -
  super-conducting magnets that confine, shape and
  contain the plasma using magnetic fields
• Transformers/Central solenoid - supply
  electricity to the magnetic field coils
• Cooling equipment (crostat, cryopump) - cool the
  magnets
• Blanket modules - made of lithium absorb heat
  and high-energy neutrons from the fusion reaction
  
• Divertors - exhaust the helium products of the
  fusion reaction

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• The fusion reactor will heat a stream of
  deuterium and tritium fuel to form
  high-temperature plasma. It will squeeze the
  plasma so that fusion can take place.
• The power needed to start the fusion reaction
  will be about 70 megawatts, but the power yield
  from the reaction will be about 500 megawatts.
• The fusion reaction will last from 300 to 500
  seconds. (Eventually, there will be a sustained
  fusion reaction.)
• The lithium blankets outside the plasma reaction
  chamber will absorb high-energy neutrons from the
  fusion reaction to make more tritium fuel. The
  blankets will also get heated by the neutrons.
• The heat will be transferred by a water-cooling
  loop to a heat exchanger to make steam.
• The steam will drive electrical turbines to
  produce electricity.
• The steam will be condensed back into water to
  absorb more heat from the reactor in the heat
  exchanger.
• Initially, the ITER tokamak will test the
  feasibility of a sustained fusion reactor and
  eventually will become a test fusion power plant.

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• Fusion Reactors Inertial Confinement
• The National Ignition Facility (NIF) at Lawrence
  Livermore Laboratory is experimenting with using
  laser beams to induce fusion. In the NIF device,
  192 laser beams will focus on single point in a
  10-meter-diameter target chamber called a
  hohlraum. A hohlraum is "a cavity whose walls are
  in radiative equilibrium with the radiant energy
  within the cavity"

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• At the focal point inside the target chamber,
  there will be a pea-sized pellet of
  deuterium-tritium encased in a small, plastic
  cylinder. The power from the lasers (1.8 million
  joules) will heat the cylinder and generate
  X-rays.
• The heat and radiation will convert the pellet
  into plasma and compress it until fusion occurs.
  The fusion reaction will be short-lived, about
  one-millionth of a second, but will yield 50 to
  100 times more energy than is needed to initiate
  the fusion reaction.
• A reactor of this type would have multiple
  targets that would be ignited in succession to
  generate sustained heat production.
• Scientists estimate that each target can be made
  for as little as 0.25, making the fusion power
  plant cost efficient.
• Like the magnetic-confinement fusion reactor, the
  heat from inertial-confinement fusion will be
  passed to a heat exchanger to make steam for
  producing electricity.

All information from How Stuff Works.
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• Applications of Fusion
• The main application for fusion is in making
  electricity. Nuclear fusion can provide a safe,
  clean energy source for future generations with
  several advantages over current fission reactors
  
• Abundant fuel supply - Deuterium can be readily
  extracted from seawater, and excess tritium can
  be made in the fusion reactor itself from
  lithium, which is readily available in the
  Earth's crust. Uranium for fission is rare, and
  it must be mined and then enriched for use in
  reactors.
• Safe - The amounts of fuel used for fusion are
  small compared to fission reactors. This is so
  that uncontrolled releases of energy do not
  occur. Most fusion reactors make less radiation
  than the natural background radiation we live
  with in our daily lives.
• Clean - No combustion occurs in nuclear power
  (fission or fusion), so there is no air
  pollution.
• Less nuclear waste - Fusion reactors will not
  produce high-level nuclear wastes like their
  fission counterparts, so disposal will be less of
  a problem. In addition, the wastes will not be of
  weapons-grade nuclear materials as is the case in
  fission reactors.
• NASA is currently looking into developing
  small-scale fusion reactors for powering
  deep-space rockets. Fusion propulsion would boast
  an unlimited fuel supply (hydrogen), would be
  more efficient and would ultimately lead to
  faster rockets.

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• Cold Fusion
• In 1989, researchers in the United States and
  Great Britain claimed to have made a fusion
  reactor at room temperature without confining
  high-temperature plasmas. They made an electrode
  of palladium, placed it in a thermos of heavy
  water (deuterium oxide) and passed an electrical
  current through the water. They claimed that the
  palladium catalyzed fusion by allowing deuterium
  atoms to get close enough for fusion to occur.
  However, several scientists in many countries
  failed to get the same result. But in April 2005,
  cold fusion got a major boost. Scientists at UCLA
  initiated fusion using a pyroelectric crystal.
  They put the crystal into a small container
  filled with hydrogen, warmed the crystal to
  produce an electric field and inserted a metal
  wire into the container to focus the charge. The
  focused electric field powerfully repelled the
  positively charged hydrogen nuclei, and in the
  rush away from the wire, the nuclei smashed into
  each other with enough force to fuse. The
  reaction took place at room temperature.