European pressurized engine

Features

The EPR is a Pressurized water reactor (REFERENCE MARK). Compared to the sections REFERENCE MARK currently in service in France, the EPR has of more than circuits of safety and an increased power. The opponents estimate that this engine is in fact more complex and more difficult to control. The EPR is a pressurized water reactor, designed to meet the standards of safety enacted by the authorities of German and French safety during the Années 1990. Technically, it is based on the concepts of the N4 type (French nuclear reactor of 1450 MW) and KONVOI (German).

Evolutions compared to the preceding die, asked by the authorities of nuclear safety (French and German) which certified it, aim at limiting the risks of accidents and in particular the risk of core fusion of the engine which contains the Uranium enriched, to reduce the amounts Radiation S suitable for assign the personnel, and to decrease the radioactive emissions in the surrounding medium. According to its originators, the Probabilité of accident would be reduced of a factor 10, the level of exposure of the personnel to the Radiation S, of a factor 2, and the level of activity of the rejections, a factor 10, compared to the most recent installations in service.

In the field of the Competitiveness, the increase in power and a better utilization ratio of fuel, enriched uranium oxide with 5 % d'²³⁵U, or a mixed oxide Uranium - Plutonium (MOX), would have, according to the promoters of the EPR, to lead to a considerable reduction in the cost of nuclear kWh.

The more complete combustion of uranium would also result in reducing of 15 to 30 % production of Radioactive waste with long life, “ knowing that this progress associated with the increase with the burn-up rates will also relate to for a broad part the park actuel ”.

On the technical plan, the EPR is characterized in particular by its enclosure from containment seals made up of two walls of Béton 1,3 m thickness and a new device called “ recuperator of Corium ” intended to collect the part of the molten heart which would cross the tank, in situation of core fusion (exceptionally serious accident); otherwise, in this situation, the core materials in fusion could cross the to erase (cf the China syndrome) and to contaminate the Environnement. This system is on the other hand likely to cause violent capable vapor explosions to cause a serious accident (see further).

Engine EPR has several active and passive protections against the Nuclear accidents:

four cooling systems urgently independent, each one being able to cool the engine after its stop,
a container of radioactive escape around the engine,
a Pregnant of containment in the event of Core fusion,
of the made walls two separated thicknesses, adding up 2,6 m total thickness.

Safety of the EPR

Risk steam explosion

Various studies, of which that of the International association of the doctors for the prevention of the nuclear war (IPPNW), entitled “ Technical defects on the safety of the European engine with water (EPR) pressurisée ”, estimate that this system could cause powerful vapor explosions, capable to lead to the rupture of the containment. This problem was identified by the Authority of French safety (ASN) “ The quantity of water which could be present in the well of tank and the room of spreading out at the time of the opening of the tank must be limited by design. The possibility of an important vapor explosion during the flooding of corium must be avoided and the loadings resulting from interactions molten water-heart must be taken into account in the conception ”.

Such an explosion however requires a cast iron of the heart and the opening of the reactor vessel, which is one of the most serious accidents for a pressurized water reactor. Such an event never occurred on the whole of the current fleet of REFERENCE MARK (during the accident of Three Mile Island, there was cast iron partial of the heart well, but the tank held). Areva, manufacturer of the EPR, affirms to have undertaken probabilistic studies showing that the frequency of this event is limited to $10^ {- 6}/{year}$ (an accident of this type all the million years of operation of EPR). This frequency is announced as being 10 times more important at the engines currently in service.

Risk of fall of plane

The containment of engine EPR was dimensioned to resist the damage caused by the fall of a fighter plan. Anne Lauvergeon, chairman of Areva (manufacturer of the EPR), affirmed on July 10th, 2005 that engine EPR is “ conceived to resist all, including the falls of avions ”.

The Network “ To leave the nuclear power ” public in 2003 a document Confidentiel defense resulting from EDF made. This document details the capacity of resistance of the enclosure of the EPR and concludes that “ the case of loading suggested/selected covers a broad range of the types/masses/speeds. It reasonably covers the loadings induced by average planes/large porteurs ”. For the antinuclear ones, the formulation “ reasonable cover of the risque ” is the consent which engine EPR would not resist a crash landing carried out with a large transport aircraft.

Broad John, a British scientist “ well-known of the movement antinucléaire ”, elected by Greenpeace, studied the document classified as “ confidential défense ” emanating from EDF; in May 2006, he declares that “ The analysis of EDF seems to be technical and solid, but when one looks in detail, it does not hold pas ”, and affirms that the quantity of fuel load in a commercial aircraft could cause an explosion and that the buildings sheltering fuel could not resist the shock caused by the falls of the apparatus.

Classification secret defense of the technical informations is the polemic object; Stephan Lhomme, spokesperson of the Network “ To leave the nucléaire ”, was placed in guard-with-sight on May 16th, 2006 by Management of monitoring of the territory (DST), on requisition of the antiterrorist section of the Parquet floor of Paris, for possession of a document classified as “ secrecy défense ” relating to the safety of engine EPR with respect to the risk of fall of plane, which caused various protests. The following day, to protest against this police custody, various organizations (Network “ To leave the nucléaire ”, Greenpeace, the Friends of the Earth, etc) published on their Web site a copy of the confidential document defense.

Description

Civil engineering

Forgings

Since no engine was built recently, there no were investments of Areva NP on its production line of tank other than those necessary to the maintenance of the engines in exploitation (replacement of the lids of tank for example). Areva NP sub-contracted the manufacture of the tank of the EPR finalandais with a company Japan ease, allowing by là-même a competitor to reach its technologies. Areva NP affirms that this subcontracting is due to the times imposed by Finland for the startup of the EPR and to the completion dates of productive investments in the production line. On the other hand, Areva NP envisages to manufacture the tank of the French EPR on its line productions. The opponents with the nuclear power estimate that French nuclear industry is not any more in 2006 in capacity to answer such orders.

Comparisons

Advanced EPR compared to former engines PWR

Even if EPR is an engine which was deliberately desired " évolutionnaire" and not " strongly in; it contains despite everything a rather great number of advanced considerable which makes progress the technology of the generating PWR to loops, one tries hereafter to count some most important

1°) Advanced in the safety plan

A " récupérateur" of refractory material corium can in the hypothetical case of a fusion heart having led to boring tank to maintain it this one in the enclosure and to cool it

Basic crossings of tank of the PWR Westinghouse and Framatome of the former generations which constitute " a faiblesse" of that Ci were removed

The systems of injection of safety were reinforced and the adoption of an organization known as " with 4 times 50% " have a level of reliability more important than the preceding system while facilitating maintenance in service

From a lawful point of view, it is important to note that the German and French Authorities of Safety gave their downstream on this model of engine. This point is obviously very important in terms of credibility on the worldwide market, certification was very long and difficult within this multinational framework. This aurat certainly be possible if the concept had not been deliberately moderately innovating since as well:

the ACE Frenchwoman finds N4 improved in EPR
the ACE German finds there Konvoy improved

2°) Advanced in the exploitation//maintenance plan

With the image of what exists on the Konvoy engines the installation of many buildings was reconsidered improving in particular largely the work conditions of the operators in chage of the maintance (ergonomics accessibility)

Best ergonomics as well as the automation of a certain number of functions allowed a significant reduction of the personnel necessary to the exploitation

3°) Advanced in the performances plan

Thanks to the new steam generators the secondary pressure reaches almost 80 bars what represents the value appreciably leading to the maximum of output for a cycle with water vapaur saturated either 36% compared with 34% for the former engines. In this way for the same quantity of produced electricity the heat rejected into the environment is decreased of 9% what is not at all negligible

The tank larger, is drawn better forms " of it; bouteille" , able to receive a heart of bigger size, better protected from the neutron radiation resulting from the heart

The material of the tubes of the Steam Generators was largely improved in terms of corrosion resistance compared to the former generations

The interns tanks comprise reflectors " lourd" out of steel surrounding the heart, improving the neutron balance and protecting the tank against the neutron radiation from strong energy

Stroke of progress of EPR

EPR does not represent the vision " achevée" water reactor generating uplift with loops. This for the reason first that it acts as it was known as of a concept évolutionnaire. A good number of projections are at the same time possible and necessary, for example:

the installation of non-return valve out of tank to the image of those equipping engines BABCOK would make it possible to return the injection of safety in the event of brêche on the cold loops much more effective in " équilibrant" volumes upstream and downstream heart ferments
of it the interior discharge with the containment of the relief valves secondary would reinforce largely and in an extremely simple way management of the accidents of ruptures of the tubes of the steam generators
the implementation of an injection of safety going directly to the tank and not in the loops would eliminate the mode common existing to this level in the event of brêche on the level from the loops
the suppression or at the very least the reduction of the importance of control with soluble boron would allow

- to reinforce safety largely

- to reduce the volume of the effluents

- to reduce the rejections tritium associated with these rejections with effluents

the implementation of device passive of evacuation of the after-power to the stop would increase largely the response time necessary to the operators in case number of incidents or accidents

the implementation D principal primary pumps with asynchronous motor drowned rotor would make it possible to remove a permanent escape on this level and a device of press expensive étoupe//garniture and défiabilisant

a general organization envisaging the burial at least partial of the engine and the combustible building would largely reinforce the resistance of the engine vis-a-vis the aggressions of the missiles types, falls of planes, and seisms

an increase in the power even if it is not really undoubtedly the priority will reveal over the long period an additional asset of competitiveness

EPR in construction or project

Finland

Olkiluoto 3 (Customer: TVO, Brought into service envisaged in 2011)
the construction of a second EPR, on the site of Loviisa, would be being studied.

France

Flamanville 3 building (Owner: EDF, brought into service envisaged in 2012).

China

AREVA and the Chinese electrician CGNPC announced, on November 26th, 2007, the signing of a bearing contract on the construction of two nuclear plants EPR on the site of Taishan in the province of Guangdong. Associated with a supply agreement of fuel and services, it is about the largest contract of the history of the civilian nuclear (8 billion euros).

The signing of this contract made following more than three years of discussions between Chinese AREVA and its interlocutors. AREVA had taken part in particular in 2006 in an invitation to tender in China for the construction of 6 nuclear reactors of third generation. At the end of almost three years to negotiation, Westinghouse gained a contract for the construction of 4 AP1000, at the price of important a Technology transfer.

The United States

an American EPR could be built on the site of Calvert Cliffs.

The the United States, the electrician Energy Constellation and Areva joined within the consortium UniStar Nuclear to promote the EPR. The name of the engine was changed into US-EPR (Custom-Evolutionnary Power Reactor). The application of license to the American authorities of safety is planned for the end of 2006 and the one first construction seems possible for 2010-2011.

Others

on May 25th, 2007, EDF and Areva announced to consider the construction of one or more EPR to the the United Kingdom. They should for that engage soon a step of certification near the British authorities.
Of engines EPR could also be built in South Africa and in Canada, Morocco was also evoked as well as Egypt.
an engine EPR could be built in Libya, officially to feed a desalination plant of sea water, which question the Network " To leave the nucléaire" who sees a pretext there. President Nicolas Sarkozy contradicted, at the time of his stay in the USA in August 2007, the project of sale of an engine EPR to the lybian mode. However, according to the daily newspaper the Parisian one, a spokesperson of the ECA explained why " the French group Areva was requested by the Libyan authorities as of June to present the model all-last of EPR" nuclear plant;.

See too

Related bonds

Energy policy of the European Union
Nuclear plant
List of the nuclear plants in France
Nuclear energy

External bonds

the Page of EDF - Project superintendent of the EPR in France

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