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Nuclear Energy. By: Edward Tsui , NBJ, Miranda Tang, Sean Li. Introduction. Concept of the possibility of absorbing energy from atoms came from the 30s First uses of “Nuclear” energy is focused in military uses Civil use of Nuclear Energy came popular in the 80s
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Nuclear Energy By: Edward Tsui, NBJ, Miranda Tang, Sean Li
Introduction • Concept of the possibility of absorbing energy from atoms came from the 30s • First uses of “Nuclear” energy is focused in military uses • Civil use of Nuclear Energy came popular in the 80s • Huge debate on whether to use nuclear power • Provides 12~13% of the world’s electricity currently
World Usage of Nuclear Energy/ Energy as general • Nuclear Energy produces 75% of France’s electricity • By 2030 China is projected to be using almost as much oil as the USA does now • Consumption is now twice of the rate of discovery • Total energy demand is expected to double between 2002 and 2030 (From 16,000 billion kWh in 2002 to a projected number of 31,600 billion kWh)
Concept of Nuclear Power • Through the process of fission • Mass energy is released by splitting large atoms to produce medium sized atoms • Usually Uranium U235 / Plutonium 239 are being used as nuclear fuel • A constant, clean (to be disputed) and scalable energy source
Step 2 – Enrichment/Purify • Uranium as mined cannot be fed directly into a power station. • Usually concentrated and made up to special fuel rods (metal bars) • Enrichment requires the uranium to be in the form of gas • Increases the proportion of U-235 from 0.7% to ~3.5% (Usually)
Step 3 – Fuel Fabrication • Enriched UF6 gas is converted to uranium dioxide (UO2), which is formed into ceramic fuel pellets by baking it at a high temperature (over 1400°C). • Pellets are encased in metal tubes • To be put in bundles as fuel in the Nuclear Reactor
Step 4 – Reactor/ Electricity Production • Energy released from fission would be used to generate steam (basically boiling water) • Through the steam line the steam would be used to move the steam turbine then produce electricity through the generator • Exact same process as using coal
Step 5 – Disposal/Waste • Usually nuclear fuel would be changed once per months • Nuclear waste could be disposed in secured storages (some underground) • Or it could be reprocessed and used again
Advantages of using nuclear power – Compared with coal • The only major fuel options for base-load energy production is either Coal or Nuclear Power • About 20,000 times as much coal is required in mass terms of electricity production • Coal will be used up in about 150 years, however more uranium resources are to be developed
Advantages of using nuclear power- Compared with coal • Waste produced from coal plants directly emits upon the atmosphere • Nuclear waste could be stored or to be reused • Transportation costs are very high for coal • Nuclear power plants could provide work for local industries which build the plant and also minimize long term commitments to buying fuels aboard
Advantages of using nuclear power – Compared with renewable energy • Some environmental movements launched the “blind and anti-scientific opposition to this proposition” and “abandoned science and logic in favor of emotion and sensationalism” • To power the entire world with 50% wind energy, you would need about one percent of the world land • Nuclear energy’s greenhouse gas is even below solar power
Advantages of using nuclear power- Compared with renewable energy • Wind and Solar is simply a type of dilute, variable energy • Typically getting one gigawatt of wind power from 250 square miles and one gigawatt of solar power from 50 square miles • Basic arithmetic problem • There are not a fourth choice for base-load electricity ( Fossil fuels: 66.1%/ Hydro: 16.1%/ Nuclear: 15.7%)
Advantages of using nuclear power- Compared with renewable energy • Small and cheap nuclear reactors are being made for developing countries • Could be used for purifying water
The Megatons to Megawatts program • An important source of nuclear fuel is the world’s nuclear weapons stockpiles • Contain a great deal of uranium enriched to over 90% U-235 (about 25 times the proportion in most reactor fuel) • The 500 tonnes of weapons stockpiles of Russia is equivalent to about 153,000 tonnes of natural uranium, more than twice the annual world demand
Nuclear Fusion • The opposite of Nuclear Fission – Combining multiple atomic particles to produce energy • The is what provides the sun and the stars with the energy to shine continuously for billions of years
Disadvantages of nuclear energy: • Nuclear energy involves with large and dangerous amount of radiation • A single nuclear disaster could affect a large region of area • Accidents did occur in the history of nuclear energy, infamously, (Chernobyl 1986 / Three Mile Accident 1979/ Fukishima 2011)
Disadvantages of nuclear energy • Countries, such as Iran and North Korea could be using civil nuclear power plants as a disguise to develop nuclear weapons • Trucks loaded with Nuclear-related materials and nuclear plants could be an attack target
Conclusion – Energy Saving • Nuclear Energy should be used appropriately • Energy saving is the only solution to the problem • The first world behaves like an addicted smoker, distracted by short term benefits and ignorant of long-term risk • There would never be enough energy for the world to use
Conclusion- Energy Saving • However a significant reduction seems unlikely • Uneven world distribution of energy resources