Nuclear Reactors

The first commercial nuclear power plant in the US was built in 1957 in Shippingport, Pennsylvania.

The first commercial nuclear power plant in the world was built in 1956 in Calder Hill, UK.

Nuclear reactors can vary in size depending on their purpose. A typical commercial nuclear reactor used for generating electricity can be around 1,000 megawatts in size, which is enough to power a city of about one million people. Small modular reactors (SMRs) are also being developed that can be much smaller in size, around 50-300 megawatts.

The sun actually is a giant nuclear fusion reactor, not fission like you see here on earth. The difference is that on earth, we can split atoms to break bonds and release energy. The result is weapons and electricity and nuclear waste. The sun however fuses atoms together to make new ones. An example of this is two hydrogen---->1 helium, 1 helium and one hydrogen----> one Lithium, etc. Energy is again released when the atomic bonds are broken and atoms remade, though no nuclear waste this time.

A breeder reactor generates (in a way) new fuel, sometimes more fuel than it uses, by converting non-fissionable isotopes into fissionable isotopes, through neutron capture.

The nuclear reactor was invented in 1933 by Leo Szilard, in London, but he did not try to build one.

The first functioning nuclear reactor, CP-1, was designed and built in 1942 by Enrico Fermi, in Chicago, IL.

disad: very toxic waste that if not contained can cause a lot of damage and spread (ie chernobyl) adv: these days waste is contained in state of the art sealed containers and does not otherwise harm anyone. also a small amount of matter creates a large amount of energy... so there is little fear that we will run out of it

March 12, 2011

Some have answered that "none of the nuclear power plants have exploded in Japan"

This is technically true. The explosion at the power plant was actually of hydrogen gas in a containment building. It was not a "nuclear" explosion. It was not an explosion of the power generation material. The water used to cool the nuclear rods became so hot that the hydrogen was split off the water molecules. Eventually enough hydrogen collected that it exploded. That is what you see in the video linked above.

There were two such explosions. This is the second.

Before the Fukushima Daiichi Disaster, there were 54 operational nuclear reactors in Japan. Three of those melted down, and one had problems that rendered it inoperable. The government has decided the other two reactors at Fukushima Daiichi cannot be restarted. Also, as other reactors have been shut down for maintenance or refueling, they have not been restarted, with the result that now, in early December 2011, only eight Japanese reactors remain in operation.

Iran's first nuclear power plant, Bushehr I, is expected to be operational in 2009. There are no current plans to complete the Bushehr II reactor, although the construction of 19 nuclear power plants is envisaged. Iran has announced that it is working on a new 360 MWe nuclear power plant to be located in Darkhoyen.

No. Australia's only commissioned nuclear reactor is operated by ANSTO, primarily for nuclear medicines, neutrons for scientific research and irradiation services.

http://www.ansto.gov.au/discovering_ansto/anstos_research_reactor.html

people got involved..

it sucks, but yeah, blame the humans.

this is why nuclear is not everywhere, because there are people everywhere to screw it up

to tell you what happened with Chernobyl, first you have to understand how a nuclear reactor works.

in a nutshell, you have a fissionable material, it is condensed, and condensed until it produces heat on its own. these heat rods are kept in sheaths like a sword, and they keep the material cool.. there are many rods, and the more rods in the pool brought out, the higher the temperature of the water in the pool. it makes steam, and the steam spins a turbine to make electricity, and the power goes to your home.

Chernobyl happened because they were testing how to make more energy. see, they probably had a similar problem there, that they have here. People want power for their cell phones, and ipods, but they dont want to produce it, they dont like coal, they dont like nuclear. The people wouldnt allow another reactor to be built, so they were testing how the reactor would respond with more rods out of the sheathes than what was considered safe operation. (we have 50 rods, why do we only use 10 at a time? sort of thing)

so they had the normal 10 rods extended out into the pool to heat the water, then they told the computer to bring a couple more out, and a couple more, and they were really impressed, they were boiling twice the water in half the time, it was an exponential increase with just a few more rods, not double.

but what happened is that they didnt understand that the rods can heat up themselves, because they are so dense, but they can also heat the other rods, and they did. the rods got so hot they warped, then when they tried to put them back into the sheathes, they couldnt, and the reactor got so hot they couldnt put water into it fast enough to keep it cool, and it blew.

Chernobyl is still poisoned today. when the 20 or so rods out of the 50 blew, it didnt use all the material and detonate like an atomic weapon, but it detonated some, but blew the rest around, like a dirty bomb. the radiation is nearly gone, but all the plants an animals an people are dead/dying/toxic due to exposure.

nuclear is a wonderful source of energy, this is why the navy has reactors in nearly all the aircraft carriers, there are safeguards in place, and people are not allowed to mess with it. on land, its a different story, and its all about the money money money, and safeguards are put by the wayside. if they can produce double the power using a fraction more rods, they will. and this is how greed destroyed a beautiful town and lives, and the complete nuclear industry

One of the advantages of the nuclear reactors is that they do not produce smoke particles that pollute the environment and therefore lead to the acidic rainfall. The other advantage is that it is easier to control the output of a nuclear reactor to fit a given need. One of the disadvantage of the nuclear reactors is that the disposal of the nuclear waste is very expensive.

thousands of people died, or were at health risk.

The first sustained Nuclear Reaction was in CP-!, a pile of Uranium and Graphite blocks assembled by a team under the supervision of Enrico Fermi. Fermi collaborated with Leo Szilard, discoverer of the chain reaction

The first demonstration nuclear reactor was built in USA by Enrico Fermi in Chicago Stadium. Fermi was an Italian Physicist, best known for his work on Chicago Pile-1 (the first nuclear reactor).

on 26 June 1954, in the town of Obninsk, near Moscow in the former USSR, the first nuclear power plant was connected to an electricity grid to provide power to residences and businesses. Nuclear energy had crossed the divide from military uses to civilian applications.

After the steam explosion which blew the top of the reactor off, the graphite moderator was exposed to air, and as it was hot enough it started to burn. Decay heat from the fuel would have contributed to the high temperature as well. Graphite burns well in air, as barbecues demonstrate.

See Wikipedia 'Chernobyl disaster' for more information on the development of the disaster.

I don't know that there is a technical definition of a nuclear disaster. There are two accidents that are commonly referred to as disasters. One is the well known Chernobyl disaster, and the other is the Kyshtym disaster, both of which were in the former USSR. The Windscale fire, Three Mile Island Accident, and other problems are referred to as accidents.

There is an International Nuclear Event Scale, which rates events on a scale of 1 (least important) to 7 (most important). On this scale, the Chernobyl Disaster is rated at a 7, and the Kyshtym Disaster is rated at 6. Three Mile Island Accident is rated at 5, as is the Windscale Fire, and two other accidents.

There is a link below to an article on the International Nuclear Event Scale.

There are two, very large negatives to nuclear power.

1. The possibility of a nuclear meltdown. The past fifty years of nuclear power has seen two meltdowns and one close call. These issues could easily destroy hundreds of square miles of land and conceivably kill or inconvenience those that live in these areas. Chernobyl and the current crisis in Japan are examples of absolute worst case possibilities. Three Mile Island is a classic example of a system working to prevent a meltdown.

2. The issue of storing the spent radioactive material is problematic currently. There have been proposals for permanent disposal and even methods proposed to decrease the levels of radioactivity in this material. Politics has prevented these systems from being implemented.

The only current alternative to nuclear power though is coal or fossil fuel plants. The alternative energy proposals can assist in very small terms and in very small amounts. Coal causes hundreds of deaths each year in terms of mining operation issues and black lung. Whether or not these known environmental and health issues are offset by the unknown issues of a meltdown have been debated for decades. The United States has a current policy of taking the known annual deaths from coal as being safer and less problematic than the unknown issues of Nuclear.

1. fuel
2. moderator
3. cooling system
4. control rods
5. SCRAM system

Components in the reactor inside the primary shielding will be radioactive, even after all the fuel has been removed. Provided everything is monitored and assessed properly and health physics advice followed by the operators, there should be no need for anyone to be exposed to dangerous levels during decommissioning.

When a reactor has burned enough of its fuel that it cannot be made to go critical by pulling all the control rods all the way out, it has reached the end of its useful life. There is a lot of unburned fuel left in the fuel elements, but not enough to achieve criticality the way the reactor core is set up. (Only a small percentage of the fuel is actually burned.) Usually the operators of a nuclear plant will take a reactor out of service and refuel it a bit before this. And military reactors will be taken offline sooner and refueled because of the requirement that the reactor be able to be brought critical at what is called the "peak xenon" point. Generally speaking, the core is removed and put in a storage pool that provided cooling and shielding. The core will remain there until it can be disassembled into fuel bundles and the bundles packed up and moved to a long-term storage facility for a century or a few. It is unusual that the fuel elements are reprocessed to remove the remaining fuel because of the presence of a lot of extremely radioactive fission fragments.

Applications of uranium:

- nuclear fuel for nuclear power reactors

- explosive for nuclear weapons

- material for armors and projectiles

- catalyst

- additive for glass and ceramics (to obtain beautiful green colors)

- toner in photography

- mordant for textiles

- shielding material (depleted uranium)

- ballast

- and other minor applications