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Sources of energy  

5 - Nuclear power

Nuclear energy accounts for 6-7% of world energy production and accounts for more than 20% of electricity supply. Nuclear energy is a very dense form of energy (1 kg of Uranium used in a water reactor is the energy equivalent of 10 metric tonnes of oil, 60 reactors supply 80% of the electricity supply in France) and is well suited for the production of energy on a large scale. Most installations use the " open cycle ", i.e. without reuse or recycling of materials used in spent fuel. The result is that less than 1% of the energy potentially contained in the fuel is used. Uranium reserves are like those of gas, therefore about 40 years (resources guaranteed at <80$ per kilo of uranium). The use of so-called "fast neutron reactors" helps extract around 100 times more energy from natural uranium than by conventional methods, thus postponing the moment that resources will run out in terms of several millenniums. This is a more complex technology, but has been proven to be feasible.

The safety issue in nuclear installations came to a head around the Chernobyl accident, where the Ukrainian power station is of a rather particular type (for further information: site of the Nuclear Protection and Safety (Institut de Protection et de Sûreté Nucléaire IPSN, Site IPSN). Nevertheless, a nuclear reactor is the energy production installation with the lowest environmental impact. One of the special features of nuclear power is that right from the start, this energy industry has looked seriously into the question of its waste. It must be remembered that quantity is limited and there is no leakage at the source. Management of low and average waste is well controlled at an industrial level. The future of long-lasting and highly activated waste is under study in the framework of the law passed in 1991 (Bataille law). This work is divided up into three parts : transmutation of long-lasting isotopes, burial of waste and long-term safe storage. The use of nuclear energy enables France to be among the industrial nations with the lowest emissions of CO2 per unit of energy produced :

Sweden France Germany Denmark UE US
1.28 1.57 2.63 3.17 2.38 2.6

Emission of CO2 per unit of energy produced in ( t.CO2/tep)


Waste produced in France

Energy Advantages Drawbacks Production of 1000 MWe during one year (1)
  • no pollution nor release of greenhouse gases
  • suitable for large scale production
  • Waste
    management over long periods
  • acceptance by the general public
  • no passive
 25 tonnes of enriched Ur at 4%


6 - Energy from fusion

Fusion is quite another form of nuclear energy. It includes all the advantages of "conventional" nuclear power (energy density and no operating pollution) while at the same time aiming at the reduction and even the elimination of its drawbacks (no long term waste, intrinsic safety and abundant fuel).


Advantages Drawbacks Production of 1000 MWe during 1 year
  • feasibility remains to be proven
  • concerns the long term (2050)
  • high investment
  • complex technology
100 kg of D and 150 kg of T


7 - Conclusion

Energy production based on the use of fossil fuels will become more and more difficult on account of raw materials themselves running out and the ecological consequences of this type of production. There is absolutely no doubt that renewable energy has a considerable development potential, above all in a world where environmental considerations are taking on greater and greater importance. This form of energy has its pros and cons, and it would not be very realistic to imagine all energy limited to renewable energy on its own. It is obvious that the different energy sources, some suitable to a decentralised electricity market and others more suitable for centralised production in modern high population density areas, complement each other. To be viable, these energy forms should naturally satisfy economic requirements but also take into account environmental demands, operating safety and availability of resources. Energy from fusion, with its feasibility as yet to be proven, meets all these requirements.


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