1 / 15

Nuclear Energy

rowdy
Download Presentation

Nuclear Energy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. http://www.energy.gov/energysources/nuclear.htmhttp://www.eia.doe.gov/fuelnuclear.htmlhttp://science.howstuffworks.com/nuclear-power1.htmhttp://blogs.princeton.edu/chm333/f2006/nuclear/02_mining_and_conversion/04_can_uranium_mining_be_safe/http://nextbigfuture.com/2007/07/constructing-lot-of-nuclear-power.htmlhttp://www.nrc.gov/reading-rm/doc-collections/cfr/http://www.energy.gov/energysources/nuclear.htmhttp://www.eia.doe.gov/fuelnuclear.htmlhttp://science.howstuffworks.com/nuclear-power1.htmhttp://blogs.princeton.edu/chm333/f2006/nuclear/02_mining_and_conversion/04_can_uranium_mining_be_safe/http://nextbigfuture.com/2007/07/constructing-lot-of-nuclear-power.htmlhttp://www.nrc.gov/reading-rm/doc-collections/cfr/ Nuclear Energy

  2. Overview The United States has 104 commercial nuclear reactors which currently produce about 20% of our national electricity. Inside a nuclear power plant, uranium atoms are split apart in a process called fission which releases heat energy. This heat energy is used to boil water in the core of the reactor to produce steam. The steam then powers the turbine which in turn generates electricity.

  3. Advantages • During the electricity generating phase, nuclear power is considered by many to have the lowest impact on the environment -- air, land, water, and wildlife - of any major energy source. • The cost of the fuel is not a major factor in the price of electricity produced by nuclear power plants so a sharp rise in the cost of uranium would have a small effect on the cost of the electricity. • Known uranium sources are expected to last the world for about a century at the current rate of usage. • Since uranium is easily mined in the U.S. we can assume that we will not have problems with obtaining the resource. • Uranium is also mined in other mountainous regions around the world so competition will not be a problem.

  4. Disadvantages • Nuclear plants are expensive to build- at least $12 billion or more apiece, and they take 4-5 years to build plus time for permits. • The risk of radiological catastrophe from a serious accident or attack. • Piles of lethal radioactive waste stored at reactor sites. • The proliferation dangers and ties to nuclear weapons development.

  5. Disadvantages Continued • Many phases of the nuclear cycle require fossil fuels to process so nuclear energy is not carbon emission free. • It takes about 200 tonnes of U308 per year to keep a large nuclear reactor running. Uranium mining is not a pretty sight. • Electricity generating plants using nuclear power are considered to have the least effect on the local environment, but the problem is that the effects that it does have are devastating and long term.

  6. Economic Considerations • Nuclear power plants are relatively expensive to build and the cost may have doubled in the past 2 years to $5-10 billion for a one reactor plant to as much as $24 billion. The need to use special materials, and to incorporate sophisticated safety features and back-up control equipment raises the cost of building a nuclear power plant significantly higher than for coal or gas-fired plants. Once the plant is built the operating cost is much the same. It is estimated that new reactors would cost up to $6,000 per kilowatt of capacity to build. • Cost of capacity • It may be possible to build a facility in 4-5 years and 2 more for licensing and approvals. • Nuclear plant construction is not constrained by building materials • In 2008 the average cost of uranium UX-U3O8-SPT per pound was $106.90 and expected to be $91.90 in 2009.

  7. Economic Considerations • There are additional costs for nuclear power of disposing of waste, insuring plants against an accident, decommissioning the plants. • Security and financial backing investors will not take a risk on nuclear plants unless there are government loan guarantees which promise to pay back loans if the borrower — in this case, the nuclear plant builder — defaults. Congress passed an appropriations bill at the end of 2007 which provided for $38.5 billion in loan guarantees, with more than half reserved for nuclear, one fifth for coal, and the rest for renewables and efficiency.

  8. Environmental Considerations Continued • During the mining of uranium, in addition to radon gas , ore dust can be blown by the wind, and contaminants can be leached and seep into surface water bodies causing such problems as lung cancer and acid rain. • Acid plants which produce acid for milling operations release large amounts of sulphur dioxide (SO2), a major part of acid rain. • Any mining process is going to pollute the nearby water. In uranium mining, it is very dangerous due to radioactive and chemical pollution. • Reactors require huge amounts of cooling water which is why they’re often located near rivers, lakes or oceans. Reactors with cooling towers or ponds can use 28-30 million gallons of water per day.

  9. Environmental Considerations Continued • The 48 reactors with once-through cooling systems use far more water (up to 1.5 billion gallons per day). A typical two-unit reactor using once-through cooling takes in about a square mile of water, 14 feet deep, each day. • Marine life is devastated by being sucked into the reactor cooling system or due to the rise in temperature up to 25 degrees hotter than the water into which it flows.

  10. Legal/Regulatory Considerations The Nuclear Regulatory Commission (NRC) will license a plant for 40 years. After that they can renew their license or decommission the plant. Decommissioning means shutting down the plant and taking steps to reduce the level of radiation so that the land can be used for other things. The NRC requires that the decommissioning process can take no more than 60 years.

  11. Legal/Regulatory Considerations Continued Anything nuclear requires a great deal of government oversight. Internationally several groups have been formed to oversee the nuclear industry. • The oldest is the Nuclear Non-Proliferation Treaty (NPT ) formed to limit the spread of nuclear weapons. • The Global Nuclear Energy Partnership (GNEP) began in 2006 to promote the use of nuclear power and close the nuclear fuel cycle in a way that reduces nuclear waste and the risk of nuclear proliferation.

  12. Safety factors • After 9/11, the Nuclear Regulatory Commission, (NRC) established the Office of Nuclear Security and Incident Response. • The U.S. Congress passed more stringent requirements and the Energy Policy Act of 2005. • In addition to the safety issues involved at a nuclear power plant, plutonium is used in nuclear weapons. • The creation of plutonium during nuclear reactions is a serious threat to our nation and the world. The increase of nuclear materials, technology and know-how cannot be separated between nuclear power and nuclear weapons.

  13. Anticipated Status • All phases of the nuclear fuel cycle are being improved for safety and security, including methods to reduce the threat of plutonium. • A reprocessing system recently introduced in Japan (in which the plutonium is never separated from the uranium) can make it much more difficult for terrorists to use civilian materials to manufacture weapons. • Other nations look to the United States as a model in nuclear safety, non-proliferation, security and in repository science.

  14. Nuclear fusion is another process that scientists are hopeful will someday (possibly by 2050) provide an endless supply of energy for generating electricity. Nuclear fusion uses uranium by joining uranium nuclei in a reaction that gives off heat and light. With nuclear fusion there would be less radioactive waste than with nuclear fission, but scientists have not yet found a way to make this process viable.

  15. Summary • Nuclear energy, due to being perceived as the cleanest source of electricity, will likely grow rapidly over the next 40 years. • A great deal of research and development are needed due to the cost of the plants and time required to build them, the disposal and safety of waste from uranium production, and the creation of plutonium in the process. • Since nuclear energy requires a fuel, (uranium) it will have some of the same supply problems as petrochemicals in the distant future. • Scientists will continue fusion research in order to make it a viable process to generate energy.

More Related