Atomic energy

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Introduction to atomic energy.

  1. Nuclear energy
    1. Nuclear fission
    2. Uranium
    3. INES
    4. IAEA
    5. Nuclear fusion
    6. ITER & DEMO projects

Nuclear energy is the fifth energy used throughout the world with a total consumption amounting to 6 %. It covers 13.8 % electricity world production.

Nuclear fission:

Fissile energy is the energy produced by non-renewable primary resources (uranium, plutonium) not emitting Greenhouse Gas Emissions (GGE) but producing radioactive wastes.

Discovery and invention:

Otto Hahn and Friedrich Strassman, German people, discovered in 1938 nuclear fission (uranium getting fragmented into two lighter nuclei by neutron bombardment. Their discovery was published on 16th January 1939. On 26th January 1939, Frédéric Joliot-Curie, born on 19th March 1900 in Paris, French, understood that a chain reaction might be possible. In February 1939, Frédéric Joliot-Curie and his team demonstrated scientifically this chain reaction. On 4th May 1939, Frédéric Joliot-Curie and his team filed three patents under the names Case no.1, Case no.2 and Case no.3. This latter case was for military use : it is the patent of atomic bomb. The first two patents concerned the nuclear fission for industrial and domestic use.

nuclear reactor world repartition

Other countries own nuclear reactors but only a few (lower or equal to 2). For example, there are Brazil, Mexico, South Africa, Argentina, Pakistan, and so on.

Different generations of nuclear reactors:

Up to now, there were three evolutions of nuclear reactors. A fourth one is being studied.

The first generation (UNGG – Uranium Natural Graphite Gas) does not exist any longer, it is dismantling. These reactors had been built before 1970.

The second generation concerns reactors built between 1970 and 1998 (PWR – Pressurized water reactor), still in service. There exist all kinds of reactors, such as AGR (Advanced Gas Reactor), BWR (Boiling Water Reactor), HWR (Heavy Water Reactor), for example. This generation supplies us with light. It is operated with pressurized water and is not yet dismantling.

The third generation has just emerged (PWR).

reactor pwr reacteur epr

It is a French-German reactor. It is a second generation evolution. Its purpose is to make electricity production more secure and more profitable. PWR uses in the primary circuit pressurized water to extract the heat produced by the nuclear fission. Inside the reactor, PWR will be able to use a mixture of uranium and plutonium : MOX. This will give a better output (less fuel to produce the same quantity of electricity). Innovative generators contribute to increase this output. The first reactor of this kind is in Finland. The second one will be operative in France in 2012. It will create an energy amounting to 1 600 MegaWatts and will be able to supply electricity to some 600 000 houses. And also, 2 other reactors of this kind are being built in China.

Reactors from the fourth generation are quite different. It is a technologic rupture. Six reactor types are presently studied at Forum Generation IV. The six types are HTR (High Temperature Reactor), SCWR (Supercritical Water Reactor), GFR (Gas-cooled Fast Reactor), SFR (Sodium Fast Reactor), LFR (Lead Fast Reactor), MSR (Molten Salt Reactor). The first power plants with 4th generation reactor will be introduced between 2030 and 2040, as French Atomic Energy Agency says. These will be based upon resource economy : minimizing radioactive wastes, but also to be used for something else than electricity production (heat production for industry). Fast neutrons mechanisms used in these 4th generation reactors will enable to use uranium in a better way. In effect, inside second and third generation reactors (pressurized water), the not-fissile part of uranium 238 is not used. It will then be used in fourth generation reactors. That will allow to produce 50 more times electricity with the same uranium mass. This economy will extend the shelf life of uranium resources presently proved to 2550 years. Remember that uranium is 1000 times more abundant than gold on earth. Moreover, fourth generation reactors will benefit from a transformation system of wastes into tomorrow energy. In effect, presently, radioactive wastes are buried 100 meters underground. You should know that the radioactivity of these wastes decreases with time. 100 000 years are necessary, so that nuclear wastes come back to their natural uranium state. However, processes recently found allow to reduce this duration to 300 years.

Uranium:

Uranium is extracted in mines, then crushed into a yellow powder (yellow cake), it is little radioactive and low enriched at that time. Then, it is transformed chemically to become rich. Uranium atoms will then go into the core of the nuclear reactor. Process of nuclear fission.

Main uranium producing countries are Australia, Uzbekistan, Kazakhstan and Canada.

world uranium deposits

Note that 15 gram uranium is equivalent to 1 ton oil or 15 000 one -square meter solar panels turned on during one hour.

Nuclear disadvantages:

Infrastructures cost (power plants and chiefly their reactors) is very high. Furthermore, a nuclear park should be renewed regularly. And its price is very high.

Uranium quote is likely to evolve more and more in the future years due to more and more constructions of nuclear power plants. Since the beginning of the years 1990, uranium production is lower than nuclear industry needs. Uranium spot prices were then multiplied by 9 between 2003 and 2007. However, prices dropped again between 2007 and 2009 (then at 44.5 dollars/pound at Nymex). Considering that several countries, such as United States, China, India or Great Britain, launched important programs of nuclear power plants for the future years, it is undeniable that uranium value increases in the future years.

Note that ten years approx are required between the discovery of an uranium deposit and its development, causing low elastic offer and also industrials anticipations aiming at uprising quotes.

Nuclear wastes processing:

Fuel (nuclear wastes) is recyclable at 96 %. The left 4 % is radioactive wastes and is presently buried 100 meters underground, waiting for another invention.

Nuclear power plants do not release CO2 into the air, only steam.

Nuclear catastrophes risks:

As you know, the greatest nuclear catastrophe was Tchernobyl in 1986. IAEA reports estimated catastrophe victims at a 4-digit number. World Health Organization (WHO) estimated it at a 5-digit number. International Physicians of the Prevention of Nuclear War – IPPNW – created in 1984, counting 150 000 members in 50 countries) estimated it at a 6-digit number.

However, there are numerous present risks, with for example some nuclear power plants located on seismic faults, which might cause major damages in the future. Such is the case in Japan, among others.

There were several cases I will list hereunder due to nuclear and to its wastes radioactivity. Yet, these risks are permanently controlled by an entity called INES.

INES:

Nuclear War

In spite of the treaty ratification for non nuclear proliferation, there are numerous doubts on a future nuclear war. The nuclear weapon is a dissuasion weapon, but in the past this weapon was used (in Japan by the US during the Second World War) and might be used again. Today, several countries make dissuasive demonstrations to show their power. That is the case of Iran, or also North Korea. This results in a geopolitical tension climate that IAEA endeavors to reduce.

IAEA:

IAEA, International Atomic Energy Agency, is an autonomous international organization under the aegis of UNO.

agence-internationale-energie

It makes an annual report to UNO General Meeting and each time the Security Council requires it. Founded in 1957 and based in Vienna, in Austria, it tries to promote the peaceful uses of nuclear energy and to limit the development of its military applications.

2004 budget amounts to over 268 million dollars.

In 1968, further to the treaty ratification on the non-proliferation of nuclear weapons (NPT), IAEA becomes liable for the supervision of a good treaty application. This treaty prevents signatory States from increasing their quantity of nuclear weapons and, for those which do not have any, from getting some.

Following oil shocks in the years 1970, and thanks to IAEA pro-nuclear lobbying, several countries intend to use massively the nuclear energy for their energy requirements, IAEA gets then more and more controlled.

At present, 139 countries are IAEA members. As non-member countries, there are North Korea (which quitted on 13th June 1994), Turkmenistan, Somalia, Laos, Guinea, Fiji Islands, Bhutan.

IAEA also manages nuclear materials control organizations, such as NMC&A (Nuclear Material Control and Accountancy).

Nuclear future:

Projects are in process concerning nuclear fusion. This might revolutionize energy sector. However, it is still being studied. Research may lead to a prototype up to 2020. Concerning its start-up, it is intended for 2060 approx.

Nuclear fusion:

Fusion consists in 2 light atoms meeting to make a heavy atom. For example, an atomic nucleus of deuterium and an atomic nucleus of tritium are assembled (no resource problem, these elements are abundant and nuclear wastes deteriorate in only one century) to build a unique helium nucleus. Light nucleus fusion dispatches a large quantity of energy coming from the high interaction. This results in a mass defect (bond energy : E=mc²) as the nucleus resulted has a lower mass than the mass sum of original nuclei.

fusion nucleaire nuclear

ITER and DEMO projects:

A prototype of fusion nuclear reactor is presently in construction in France. It will be used to control the scientific and technical feasibility of the nuclear fusion as new energy source. This prototype is called ITER (International Thermonuclear Experimental Reactor). Intended for 2020 approx, it will cost 20 billion Euros. ITER project will not produce electricity but heat. It will have a heat input amounting to 500 MW. However, ITER must also test the required technologies to produce the experimental reactor “DEMO” (DEMOstration Power Plant – estimated power amounting to 1 500 MW electric), the objective of which will be to demonstrate the industrial feasibility of electricity production by nuclear fusion. This reactor should be operative up to 2050-2070.

This project is a partnership between several States, such as European Union countries, Russia, United States, China, South Korea, India and Japan, signed at Palais de l’Elysée in Paris on 21st November 2006. Since, Switzerland takes also part in the project. Brazil has applied in, and since 2007 Kazakhstan wishes to make part of permanent members.

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