We have begun our Alternative Energy projects.
Esteban - Geodesic Domes
Marlene - Nuclear Power
Josh - Hydroelectric
Jake - Alternative Energy Renewable Sources
Amelya - Alternative Transportation
We are starting with;
Who
What
Where
When
Why
Please post your initial findings here.
Final Wall Project
13 years ago
what is a nuclear power plant? is power (generally electrical) produced from controlled (i.e., non-explosive) nuclear reactions. Commercial plants in use to date use nuclear fission reactions. Electric utility reactors heat water to produce steam, which is then used to generate electricity. In 2007, 14% of the world's electricity came from nuclear power, despite concerns about safety and radioactive waste management. More than 150 naval vessels using nuclear propulsion have been built.
ReplyDeleteNuclear fusion reactions are widely believed to be safer than fission and appear potentially viable, though technically quite difficult. Fusion power has been under intense theoretical and experimental investigation for many years.
Both fission and fusion appear promising for some space propulsion applications in the mid- to distant-future, using low thrust for long durations to achieve high mission velocities. Radioactive decay has been used on a relatively small (few kW) scale, mostly to power space missions and experiments.
There are only two countries comparable, the USA and France. France gets a higher proportion of nuclear to total generation, at about 75 percent, whilst the US is at about 20 percent. But the US economy is much bigger so the actual nuclear generation is greater in the US than in France. See link below for some facts and figures, and some useful diagrams
ReplyDeletePros -
ReplyDelete1. Little Pollution
As demand for electricity soars, the pollution produced from fossil fuel-burning plants is heading towards dangerous levels. Coal, gas and oil burning power plants are already responsible for half of America's air pollution. Burning coal produces carbon dioxide, which depletes the protection of the ozone. The soft coal, which many power plants burn, contains sulfur When the gaseous byproducts are absorbed in clouds, precipitation becomes sulfuric acid.. Coal also contains radioactive material. A coal-fired power plant emits more radiation into the air than a nuclear power plant.
The world's reserves of fossil fuels are running out. The sulfurous coal which many plants use is more polluting than the coal that was previously used. Most of the anthracite, which plants also burn, has been used up. As more soft coal is used, the amount of pollution will increase. According to estimates, fossil fuels will be burned up within fifty years. There are large reserves of uranium, and new breeder reactors can produce more fuel than they use. Unfortunately this doesn't mean we can have an endless supply of fuel Breeder reactors need a feedstock of uranium and thorium, so when we run out of these two fuels (in about 1000 years), breeder reactors will cease to be useful. This is still a more lengthy solution to the current burning of coal, gas, and oil.
2. Reliability
Nuclear power plants need little fuel, so they are less vulnerable to shortages because of strikes or natural disasters. International relations will have little effect on the supply of fuel to the reactors because uranium is evenly deposited around the globe. One disadvantage of uranium mining is that it leaves the residues from chemical processing of the ore, which leads to radon exposure to the public. These effects do not outweigh the benefits by the fact that mining uranium out of the ground reduces future radon exposures. Coal burning leaves ashes that will increase future radon exposures. The estimates of radon show that it is safer to use nuclear fuel than burn coal. Mining of the fuel required to operate a nuclear plant for one year will avert a few hundred deaths, while the ashes from a coal-burning plant will cause 30 deaths.
3. Safety
Safety is both a pro and con, depending on which way you see it. The results of a compromised reactor core can be disastrous, but the precautions that prevent this from happening prevent it well. Nuclear power is one the safest methods of producing energy. Each year, 10,000 to 50,000 Americans die from respiratory diseases due to the burning of coal, and 300 are killed in mining and transportation accidents. In contrast, no Americans have died or been seriously injured because of a reactor accident or radiation exposure from American nuclear power plants. There are a number of safety mechanisms that make the chances of reactor accidents very low. A series of barriers separates the radiation and heat of the reactor core from
the outside. The reactor core is contained within a 9-inch thick steel pressure vessel. The pressure vessel is surrounded by a thick concrete wall. This is inside a sealed steel containment structure, which itself is inside a steel-reinforced concrete dome four feet thick. The dome is designed to withstand extremes such as earthquakes or a direct hit by a crashing airliner. There is also a large number of sensors that pick up increases in radiation or humidity. An increase in radiation or humidity could mean there is a leak. There are systems that control and stop the chain reaction if necessary. An Emergency Core Cooling System ensures that in the event of an accident there is enough cooling water to cool the reactor.
Cons -
ReplyDelete1. Meltdowns
If there is a loss of coolant water in a fission reactor, the rods would overheat. The rods that contain the uranium fuel pellets would dissolve, leaving the fuel exposed. The temperature would increase with the lack of a cooling source. When the fuel rods heat to 2800°C, the fuel would melt, and a white-hot molten mass would melt its way through the containment vessels to the ground below it. This is a worst case scenario, as there are many precautions taken to avoid this. Emergency water reservoirs are designed to immediately flood the core in the case of sudden loss of coolant. There are normally multiple sources of water to draw from, as the low pressure injection pumps, containment spray system, and refueling pumps are all potentially available, and all draw water from different sources. The disaster at Three Mile Island was classified as a partial meltdown, caused by the failure to supply coolant to the core. Although the core was completely destroyed, the radioactive mass never penetrated the steel outlining the containment structure. Several feet of special concrete, a standard precaution, was capable of preventing leakage for several hours, giving operators enough time to fix the flooding system of the reactor core. The worst case of a nuclear disaster was in 1986 at the Chernobyl facility in the Ukraine. A fire ripped apart the casing of the core, releasing radioactive isotopes into the atmosphere. Thirty-one people died as an immediate result. And estimated 15,000 more died in the surrounding area after exposure to the radiation. Three Mile Island and Chernobyl are just examples of the serious problems that meltdowns can create.
2. Radiation
Radiation doses of about 200 rems cause radiation sickness, but only if this large amount of radiation is received all at once. The average person receives about 200 millirems a year from everyday objects and outer space. This is referred to as background radiation. If all our power came from nuclear plants we would receive an extra 2/10 of a millirem a year. The three major effects of radiation (cancer, radiation sickness and genetic mutation) are nearly untraceable at levels below about 50 rems. In a study of 100,000 survivors of the atomic bombs dropped on Hiroshima and Nagasaki, there have been 400 more cancer deaths than normal, and there is not an above average rate of genetic disease in their children. During the accident at Three Mile Island in America, people living within a 50 mile radius only received an extra 3/10 of one percent of their average annual radiation. This was because of the containment structures, the majority of which were not breached. The containment building and primary pressure vessel remained undamaged, fulfilling their function.
3. Waste Disposal
The byproducts of the fissioning of uranium-235 remains radioactive for thousands of years, requiring safe disposal away from society until they lose their significant radiation values. Many underground sites have been constructed, only to be filled within months. Storage facilities are not sufficient to store the world’s nuclear waste, which limits the amount of nuclear fuel that can be used per year. Transportation of the waste is risky, as many unknown variables may affect the containment vessels. If one of these vessels were compromised, the results may be deadly.
2007
ReplyDeleteNuclear energy facts. Nuclear energy is non-renewable energy source. Read some interesting facts about nuclear energy.
Nuclear energy is energy that is released either by splitting atomic nuclei or by forcing the nuclei of atoms together.
Nuclear energy comes from mass-to-energy conversions that occur in the splitting of atoms. Albert Einstein’s famous mathematical formula E = mc2 explains this. The equation says: E [energy] equals m [mass] times c2 [c stands for the speed or velocity of light]. This means that it is mass multiplied by the square of the velocity of light.
Nuclear energy is produced by a controlled nuclear chain reaction and creates heat—which is used to boil water, produce steam, and drive a steam turbine.
Nuclear power can come from the fission of uranium, plutonium or thorium or the fusion of hydrogen into helium. Today it is almost all uranium. The basic energy fact is that the fission of an atom of uranium produces 10 million times the energy produced by the combustion of an atom of carbon from coal.
Nuclear power plants need less fuel than ones which burn fossil fuels. One ton of uranium produces more energy than is produced by several million tons of coal or several million barrels of oil.
In France, nuclear power is the most widespread, supplying 80 percent of the country's electricity. A protest movement exists, called Sortir du Nucléaire, or "Get Out of Nuclear," but it appears to have made little headway.
Nuclear energy was first discovered accidentally by French physicist Henri Becquerel in 1896, when he found that photographic plates stored in the dark near uranium were blackened like X-ray plates, which had been just recently discovered at the time.
As of 2004, nuclear power provided 6.5% of the world's energy and 15.7% of the world's electricity, with the U.S., France, and Japan together accounting for 57% of nuclear generated electricity.
Nuclear energy (nuclear power) accounts for about 19 percent of the total electricity generated in the United States, an amount comparable to all the electricity used in California, Texas and New York, three most populous states.
There are 104 commercial nuclear generating units that are fully licensed by the U.S. Nuclear Regulatory Commission (NRC) to operate in the United States. Of these 104 reactors, 69 are categorized a pressurized water reactors (PWRs) totaling 65.100 net megawatts (electric) and 35 units are boiling water reactors (BWR) totaling 32.300 net megawatts (electric).
More nuclear energy facts:
ReplyDeleteOn June 27, 1954, the USSRs Obninsk Nuclear Power Plant became the world's first nuclear power plant to generate electricity for a power grid, and produced around 5 megawatts electric power.
Russia has begun building floating nuclear power plants. The £100 million ($204.9 million, 2 billion руб) vessel, the Lomonosov, to be completed in 2010, is the first of seven plants that Moscow says will bring vital energy resources to remote Russian regions.
The International Nuclear Event Scale (INES), developed by the International Atomic Energy Agency (IAEA), is used to communicate the severity of nuclear accidents on a scale of 0 to 7.
The Chernobyl disaster in 1986 at the Chernobyl Nuclear Power Plant in the Ukrainian Soviet Socialist Republic (now Ukraine) was the worst nuclear accident in history and is the only event to receive an INES score of 7.
Nuclear energy is released by three exothermic processes:
Radioactive decay, where a proton or neutron in the radioactive nucleus decays spontaneously by emitting a particle
Fusion, two atomic nuclei fuse together to form a heavier nucleus
Fission, the breaking of heavy nucleus into two nuclei
The sun uses nuclear fusion of hydrogen atoms into helium atoms. This gives off heat and light and other radiation.
Nuclear energy is really making a comeback because nuclear energy has virtually none greenhouse gases emission and therefore isn't warming the planet and causing global warming like some other energy sources.
Building trust and increasing confidence in the use of nuclear energy are vital elements for public acceptance in democratic societies.
Nuclear energy is now very safe source of energy because safety measures are taken to its maximum so new Chernobyl is very unlikely to happen.
Compared to other non-carbon-based and carbon-neutral energy options, nuclear power plants require far less land area. For a 1000 MW plant, site requirements are estimated as follows: nuclear, 1-4 km2; solar or photovoltaic park, 20-50 km2; a wind field, 50-150 km2; and biomass, 4.000-6.000 km2.
Nuclear power is the only energy industry which takes full responsibility for all its wastes, and costs this into the product.
Nuclear energy would be dominant source of energy by now if it hadn't been Chernobyl and Three Miles island (nuclear disasters).
Nuclear energy can be very destroying. Hiroshima and Nagasaki are to date the only attacks with nuclear weapons in the history of warfare. The bombs killed as many as 140.000 people in Hiroshima and 80.000 in Nagasaki by the end of 1945, roughly half on the days of the bombings.
Full article about nuclear energy you can read here.
i still dont khow ep
ReplyDelete