Areva - Reference Document 2016

GLOSSARIES 1. Technical glossary

> ASN ( Autorité de sûreté nucléaire ) The ASN is an independent administrative authority charged by the French State to regulate nuclear safety and radiation protection and to keep the public informed of these subjects. It reports to the French Parliament. > Assembly, fuel assembly A monolithic assembly of nuclear fuel rods filled with fuel pellets (in the case of MOX fuel, made of a mixture of uranium and plutonium oxides). Depending on its generating capacity (e.g. from 900 MWe to 1,600 MWe), the reactor core of a pressurized water reactor (PWR) contains from 150 to 240 fuel assemblies. The dimensions of the assemblies and the quantity of fissile material they contain are a function of the reactor type. > Atom Component of matter consisting of a nucleus containing positively charged or neutral particles (protons and neutrons), which account for almost all of its mass, around which negatively charged particles (electrons) spin. > Biomass Any organic matter of plant, animal or human origin. Biomass can be classified by origin, chemical composition or its use for energy. When used to produce energy, solid biomass from forestry, agriculture and agri-food activities, wet biomass such as waste, effluents, or treatment plant sludge, and other biomass may be chosen, in addition to energy crops, which are plants cultivated exclusively for energy production (algae, corn silage, soybeans, etc.). > Biomass burner Component of a biomass power plant in which a solid biomass fuel is burned. The heat released by combustion is used to raise the temperature and/or pressure of a heat transfer fluid (typically water) for different types of applications. > Biomass power plant Typically, a power plant that generates heat and/or electricity from the combustion of a solid biomass fuel. Its main components are a fuel handling system including a storage silo, a system to feed the fuel into the burner, the burner itself (including the fixed or fluidized bed combustion technology and the dog leg system), a steam turbine-generator combination, and combustion fumes to reduce the emission of pollutants to the atmosphere. > Burnup Assessment of fuel depletion expressed in gigawatt days per metric ton of heavy metal (GWd/MTHM). This is the unit of measurement for the thermal energy supplied by the fuel during its irradiation in the reactor. The term “heavy metal” designates isotopes starting with uranium and up. > BWR (boiling water reactor) Nuclear reactor moderated and cooled by light water which is brought to the boiling point in the reactor core under normal operating conditions. > Becquerel (Bq) See unit of measurement.

> Carbon credits Units allocated to companies leading projects that reduce greenhouse gas emissions. The credits can be sold to help finance the projects. Usually calculated in metric tons of CO 2 equivalent, one carbon credit represents a reduction of one metric ton of CO 2 . It can be used to compensate for greenhouse gas emissions in any sector: industrial, transportation or residential. Countries that have signed the Kyoto Protocol use carbon credits to achieve their greenhouse gas emissions reduction objectives. > Cask Structure designed to safely contain the radioactive material transported. It may include a variety of special materials, such as radiation-absorbing materials or thermal insulation materials, as well as service equipment, impact limiters, and devices for handling and securing. > CEA ( Commissariat à l’énergie atomique et aux énergies alternatives ) A public scientific, technical and industrial research organization that is in a category by itself in France. In addition to its fundamental research activities in materials and life sciences, the CEA is active in three major fields: defense and global security, energies that do not emit greenhouse gases, and technologies for information and health. It is tasked with promoting the use of nuclear power for scientific and industrial purposes and for national defense. > Centrifugation Uranium enrichment process that takes advantage of the difference in mass between the 235 and 238 isotopes of uranium, whereby a gaseous mixture of isotopes is spun at high speed and the centrifugal force is used to modify the composition of the mixture. Ultracentrifugation currently has the highest efficiency of the enrichment processes. > Chemical element Category of atoms that all have the same number of protons in their nucleus. > Cladding Sealed metal tube constituting the outside of the fuel rod in which the nuclear fuel is inserted to protect it from corrosion by the coolant and prevent the dispersion of fission products. Cladding constitutes the primary containment barrier. For pressurized water reactor fuel, the cladding is made of zircaloy, an alloy of zirconium. > Cleanup All technical operations to eliminate the risks related to industrial operations and radioactivity in a nuclear facility, consisting of decontaminating the structures, fixtures, floors and walls of the buildings. > CLIS ( Comité Local d’Information et de Suivi ) Instituted near the Bure underground research laboratory in France, it is tasked with a general mission of follow-up, information and consultation on radioactive waste management, and in particular on the disposal of such waste in deep geological formations. > Cogeneration Combined production of heat and electricity in the same power plant. One or more fuels may be used, including biomass, biogas (methane), natural gas, coal and fuel oil.

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2016 AREVA REFERENCE DOCUMENT