78. DPG-Jahrestagung, 17.-21.März.2014 Berlin 1 International role of nuclear fission energy generation, status and perspectives Robert Stieglitz, Joachim Knebel, Walter Tromm Karlsruhe Institute for Technology (KIT), Hermann-v. Helmholtz-Platz 1, D76021 Karlsruhe; [email protected], [email protected]; walter [email protected]Abstract The Fukushima incident in March 2011 caused worldwide a change in the perception of nuclear energy generation. Independent from the decision made by individual nations regarding the future use of nuclear energy for electricity generation, the number of nuclear power plants (NPP) operated worldwide has hardly changed. Essential reasons are mainly rising feedstock pric- es, increased energy demands and the simultaneous aspiration to reduce substantially the CO 2 - emission by fossil fuels. Especially emerging Asian economies are forced to an aggressive exploi- tation of all electricity generating technologies including nuclear to match their societal and eco- nomic demands. Nevertheless, the Fukushima accident initiated worldwide a new quality in the safety assessment and safety culture by considering additional man made or natural disasters. This process is reflected in enhanced bilateral or international co-operations. One of the most striking consequences is that a safe NPP operation demands a continuous retrofitting and evaluation of the plant behavior based on the current state of science and technology, which is part of the German safety practice since the Three-Mile-Island (TMI) incident. Within this article different new nuclear plant developments with enhanced safety features are presented. Although these concepts as well as their deployment options diverge considerably in design and operational strategy the major nuclear protection goals in terms of confinement, coola- bility and reactivity control, which have to be met by any plant design, remain the same. Regard- ing the operational safety increased computational capabilities allow by means of coupled multi- physics and multi-scale method to identify design weaknesses down to the pin scale of a fuel as- sembly both for steady state and also for plant transients. To master severe accidents the different plant concepts, however, yield to a considerably larger diversity of technical solutions, nearly all of which are based on passive systems that exploit the physical natural laws. A sustainable use of nuclear fuel avoiding large scale deep underground repositories inherently implies a closed fuel cycle and the deployment of fast spectrum reactors, so-called Generation –IV reactors, for which similar nuclear postulations in terms of safety on all levels have to be demonstrated. Within the ar- ticle for both operational safety and severe accident measures examples are presented to illustrate the main functionality and operational principle. 1 Present status of nuclear electricity generation – observations worldwide and in Eu- rope At present 435 commercial nuclear reactors (NPP) are operating and almost 2/3 rd ´s of the 72 plants under construction are erected in Asia [1]. More than 75% of the existing reactor fleet is light water reactors and about 85% of the new built belong to the class of pressurized water reactors (PWR). All commercially operated NPP´s produced in 2013 nearly 11.5% of the global electricity production, which is only slightly less than in the previous years. These commercial plants are complemented by approximately 240 research reactors operated in 56 countries and currently nearly 180 civil nuclear powered ships. Remarkable is that the countries engaged in new built or strongly envisaging the use of nucle- ar power as a “nuclear newcomer” belongs either to Eastern Europe or to Asia and the moti- vation to use nuclear power is mainly triggered by their societal decision to rely to a large quantity on industrial production as one major pillar of economic development- or simply as source of future wealth. The specific reasons of those societies range from vast economic de- velopment and rapidly rising electricity consumption, grid independence, fuel independence
Transcript
78. DPG-Jahrestagung, 17.-21.März.2014
Berlin
1
International role of nuclear fission energy generation, status and perspectives
The Fukushima incident in March 2011 caused worldwide a change in the perception of nuclear energy generation. Independent from the decision made by individual nations regarding the future use of nuclear energy for electricity generation, the number of nuclear power plants (NPP) operated worldwide has hardly changed. Essential reasons are mainly rising feedstock pric-es, increased energy demands and the simultaneous aspiration to reduce substantially the CO2-emission by fossil fuels. Especially emerging Asian economies are forced to an aggressive exploi-tation of all electricity generating technologies including nuclear to match their societal and eco-nomic demands. Nevertheless, the Fukushima accident initiated worldwide a new quality in the safety assessment and safety culture by considering additional man made or natural disasters. This process is reflected in enhanced bilateral or international co-operations. One of the most striking consequences is that a safe NPP operation demands a continuous retrofitting and evaluation of the plant behavior based on the current state of science and technology, which is part of the German safety practice since the Three-Mile-Island (TMI) incident.
Within this article different new nuclear plant developments with enhanced safety features are presented. Although these concepts as well as their deployment options diverge considerably in design and operational strategy the major nuclear protection goals in terms of confinement, coola-bility and reactivity control, which have to be met by any plant design, remain the same. Regard-ing the operational safety increased computational capabilities allow by means of coupled multi-physics and multi-scale method to identify design weaknesses down to the pin scale of a fuel as-sembly both for steady state and also for plant transients. To master severe accidents the different plant concepts, however, yield to a considerably larger diversity of technical solutions, nearly all of which are based on passive systems that exploit the physical natural laws. A sustainable use of nuclear fuel avoiding large scale deep underground repositories inherently implies a closed fuel cycle and the deployment of fast spectrum reactors, so-called Generation –IV reactors, for which similar nuclear postulations in terms of safety on all levels have to be demonstrated. Within the ar-ticle for both operational safety and severe accident measures examples are presented to illustrate the main functionality and operational principle.
1 Present status of nuclear electricity generation – observations worldwide and in Eu-rope
At present 435 commercial nuclear reactors (NPP) are operating and almost 2/3rd´s of the 72 plants under construction are erected in Asia [1]. More than 75% of the existing reactor fleet is light water reactors and about 85% of the new built belong to the class of pressurized water reactors (PWR). All commercially operated NPP´s produced in 2013 nearly 11.5% of the global electricity production, which is only slightly less than in the previous years. These commercial plants are complemented by approximately 240 research reactors operated in 56 countries and currently nearly 180 civil nuclear powered ships. Remarkable is that the countries engaged in new built or strongly envisaging the use of nucle-ar power as a “nuclear newcomer” belongs either to Eastern Europe or to Asia and the moti-vation to use nuclear power is mainly triggered by their societal decision to rely to a large quantity on industrial production as one major pillar of economic development- or simply as source of future wealth. The specific reasons of those societies range from vast economic de-velopment and rapidly rising electricity consumption, grid independence, fuel independence
Tanuclear (RES) a33,818GOnly apfor the Rgrid prioload fac
Fi D
based eOtherwimined. Fincludinterm bri
Knebel & Tro
d currency ther more. rast to the nage more thears. ven in Euroshare in e
tted to matc50, the mem3] according
Czech Repnd Croatia, on and at thhe lack of ab-11 states tondependent ividual counly deployedaking a glanby 2022, at
amounts in GW nominapproximatelRES to a reority accessctors of sola
igure 1: Ger
Doubtless theenergy prodise the econFrom the scng nuclear eidging optio
omm
export?), c
new built, thhan 25 year
ope the newelectricity gch the CO2
mber states g to the minp., Slovakiathe econom
he same timbundance o
o conceive nof the worl
ntries mainld. nce at Germt present thaverage in
al installed ly 16% is premarkable ss, solar photar and wind
rmany´s ele
e quite ambduction in tnomic compcientific poienergy and on to preven
ost argume
he classic nuold reactor
w-built and rgeneration, w-conformitycan select
nistry counca, Hungary, mic growth me ever stri
f fossil resonuclear as a ld region coly large scal
many´s curre total insta
n 2013 to inwind powerovided by share of 24to-voltaics d
d compared
ectricity sha
bitious climahe near terpetitivenessint of view,heat gener
nt energy po
ents or acce
nuclear counfleet [2], po
retrofitting owhich amoy goals formon their ow
cil agreemenLatvia, Lit
will cause ingent envirources and tone electric
onsidered aled NPP´s i
rent electricalled electricnstalled 35,
er, which woNPP´s. Non.9% for eledelivered 30to their inst
are 1990-20
ate protectiorm will dems of regions, each technration in theoverty and t
ss to large
ntries focus ower-uprati
of operatingounts to abomulated by
wn the meannt. Especialthuania, Esta consideraronmental rthe trend tocity productand the quitin the powe
city profile,city capacit,886GW peould fit the netheless, th
ectricity [5],0TWh and talled capac
18% (wiregulatiotric enerin turn mbines (Cmally eflong terRES shastorage vmaturitygies are isation w
13 [5].
on policy gomand comps not adaptinology and fe energy mito assure rea
scale renew
either on reing and life-
g plants has out 30%. Athe EU co
ns to attain lly in the EUtonia, Roma
able increaserequirementa certain en
tion option te diversely er class of 1
which decity of renewaeak photo-v
entire meahe intermitt, see fig. 1. wind 53TW
cities to aboind), respecon caused lrgy prices imade combCCGT), whfficient, nonrm especiaare exceedivolumes for
y of storagerequired, u
will not be m
oals and theromises froing these gfuel option ix either asasonable en
wable resou
eplacements-time exten
hardly chanAlthough Eommission the decarboU-11 (compania, Bulgae of electricts must be fnergy autar[4].
y motivated 1GWe and m
ided a phasable energy
voltaic capaan German tent product Although h
Wh correspoout 9.5% (soctively. Thilow wholesin Germanybined cycle hich are moncompetitivally targetining 50% sigr electricitye concept teunless the dematched.
e limitationsom all maingoals will bmust be co
s a midtermnergy prices
urces and
s of their nsions up
nged the urope is by 2020
onisation prised of aria, Slo-city con-fulfilled. rchy lead
basis of more are
se-out of y sources acity and demand. tion lead having a
onding to olar) and s market ale elec-y, which gas tur-
ost ther-ve. In the ng at a gnificant y and the echnolo-ecarbon-
s of RES n actors. e under-nsidered
m or long s.
Stieglitz, Knebel & Tromm
3
2 Boundary conditions for NPP deployment-Large reactors/ vs. small medium sized reactors
Considering nuclear as an option either as bridging technology or as one major pillar of the energy mix of an individual country, the question of the appropriate reactor size for the base load configuration arises immediately: large reactors (LR) or small scaled modular reac-tors (SMR) ? . The arguments for the choice of LR or SMR may be grouped in social (ac-ceptance, risk perception), political (independence, CO2 limitations), economic (resources, price, risk) or technological (technical maturity, safety performance) criteria. Mainly the deci-sion matrix is composed of mixtures of all these arguments and the ranking is strongly de-pendent on the national boundary conditions.
2.1 Economic considerations
Large NPP’s require a considerable capital investment per MWh/unit including all costs for projection, deployment, operation & maintenance (O&M) and finally decommissioning. Additionally nuclear power utilization demands a long term strategy of the energy policy and its development. Due to these high financial exposures, the long pay back times (envisaged duration of the investment 80-100 years from planning to decommissioning) present a high investment risk if entirely financed by private shareholders. Compared to coal, RES or gas fired plants the capital costs amount to about 55% [6] and hence the capital intensive invest-ment represents a strong exposure to market risks aside from other critical aspects as political frame (licensing, inspection, regulations,…) and social factors as e.g. public acceptance. As a consequence, private operators in a liberalized market often based on competition and some-times with priority access of other energy sources require a stable energy politics environ-ment. In contrast to purchase a LR there are numerous arguments for deploying SMRs as identified by [6, 7, 8] such as the need for flexible power generation for wider range of users and applications; the replacement of aging fossil fired units; the potential for enhanced safety margin through inherent and/or passive safety features; the economic consideration-better affordability freedom in upgrading; potential for integration innovative energy systems: cogeneration & non electric applica-
tions (desalination, process heat) and hybrid energy systems composed of nuclear with RES. But, according to numerous studies [6, 8] SMR are not significantly cheaper than LR´s and moreover, the capital return time is even larger than for larger reactors although they may offer a higher decision flexibility to expand their unit size. Additionally, SMR´s cannot be conceived as a simple scale reduction of a LR. Also the power output of several SMR to the grid cannot be simply considered as the sum of the modules; the SMR technology presents an entirely different product with respect to fuelling, operation but mainly with respect to the safety features and the applied technology. Among these technology issues their safety behav-ior is due to the smaller dimensions considerably different. SMR have usually a smaller spe-cific power density than LR allowing the use of a set of passive measures to master essential safety functions or even a full encapsulation of the reactor. Nevertheless, SMRs fulfill in some markets already an essential role as to act as base load source in remote regions or as grid stabilization in regions with moderate energy consumption like in China or India.
2.2 Current situation of NPP deployment
More than 95% of the currently operating reactor fleet belongs to the class to generation II plants, which in principle have been designed in the sixties and seventies. Also the present-ly installed generation III reactors are mainly evolutionary designs of Gen-II systems. The major reason for this development may be conceived as a risk minimization strategy of the
Stieglitz, Knebel & Tromm
4
shareholders. The comparability of Gen-II and operating Gen-III plant enables to a considera-ble extend the use of the accumulated experience of the currently operating fleet and therefore it facilitates the licensing aspects. The designs rely on well proven physics principles and no technological leaps are required. All aspects together yield for the operating Gen-III reactors a similar performance and sustainability as for Gen-II units. Another class of Gen-III reactors currently under construction in USA and China are very innovative; they rely mainly on novel passive safety features to assure core coolability e.g. in case of Loss-of-Coolant (LOCA) ac-cidents and to remove the residual heat. What are the peculiarities of the operating Gen-III reactors?
There are essentially two drivers for the new Generation III plants, which arise from both hardened design objectives and economic design objectives. The design objectives may be subdivided in two classes- the nuclear safety and the public acceptability. Regarding nu-clear safety in Generation III units severe accident measures have been already integrated in the design to attain considerably lower core damage frequencies and a significant reduction of potential radiological consequences. Another essential feature is that external events and haz-ards are considered in design and emergency management measures, which end up in a more robust safety architecture. In order to attain public acceptability, the design is devoted to min-imize the environmental impact for all operational stages and to prevent situations, in which off-plant areas are submerged to any emergency planning.
Especially the competition with other sources hardened the economic objectives. In the front row here is the profitability of the project, which in turn demands plant availabilities of more than 90% along the whole life-time, short re-fuelling and outage durations resulting in long cycle length and reduced investments caused by design simplifications and short erection times. According to this list, LR´s are preferred to SMR units. Another economic aspect is the investment protection, which translates into anticipated operation times of at least 60 up to 80 years and a low difficult-to-repair failure rate, which in turn demands to credit mainly for proven technologies. The latter argumentation chain holds mainly for liberalized markets, where temporal economic ups or downs even at low interest rates shall allow for profits for the shareholders within a reasonable time. The frame for NPP development today is conduct-ed in contrast to former times by a set of regulations, standardizations and requirements elabo-rated in the international context of utilities [9], technical survey organizations (TSO) [10], worldwide co-operations and collaborations as well as international institutions like the nucle-ar energy agency (NEA) and the IAEA [11]. All these regulations are publicly available and continuously updated.
3 Safety concept of an NPP
3.1 General safety approach
The major protection goals for NPP´s have not been changed since the early days and scope only three aspects: confinement of the radionuclide inventory; coolability at any time irrespective of origin and source and control of reactivity. This protection goals led to the implementation of a defence in depth (DiD) strategy, for dif-ferent levels are assigned to specific reactor states from 1 to 5, see . The challenge is to pro-vide enough margins between the different levels of safety to prevent cliff edge effects. The subsequent safety demonstration is characterized by a risk informed safety strategy, in which at first the protection goals are transferred into fundamental safety functions to be provided by the individual plant system design. The individual demonstration is conducted by both proba-bilistic and deterministic methods, in which for the latter a set of initiating events (PIE) are postulated and their progression is analyzed.
Figurehydrau
Table 1
con
1 nor
2 opefail
3 desbasden(DB
4 sevcid(BD
5 posacc
3.2 Des
Asuch as all of thadditionably thetional m Es
(
e 2: Transfeulic channel
1: Safety lev
ndition
rmal
erational lure
sign sis acci-nt BA)
vere ac-dent DBA)
st severe cident
sign basis s
A nuclear poneutronics
hem are occnally charace safety per
multi-physicspecially to
a)
fer of reactols.
vel categori
aim
prevention operation o
condition tion/ identison
control ofdesign (e.gures of safe
control ofstates inclpropagation
mitigation consequenc
safety (oper
ower plant , thermal-hcurring on cterized by nrformance acs and multioday and ve
r core (a) in
zation; corr
of anoror failures
control, deification of
f DBA wig. multiple ety function
f critical p. preventionn
of radiolces
rational saf
is a complydraulics andifferent scnon-linear fand poses s-scale toolsry likely in
(b)
nto nodal m
responding
mea
rmal conhightion
etec-f rea-
contectsurv
ithin fail-
ns)
engact. of mea
plant n of
commeaman
logic off-mea
fety)
lex system,nd thermo-cales from feedbacks. significant cs to describen the near fu
model (b) an
aim, measu
asures
servative h quality n, qual. pers
trol, limitaion measuvey function
ineering saand implecontrolled
asures
mplementingasures and nagement
- plant easures
, in which mechanics micro- via This mutuachallenges te the temporuture, the en
Stieg
d then conn
ures & conse
design, construc-
onnel
ation/ pro-ures and ns
afety char-ementation
accident
g accident
emergency
different phare interconmeso- to m
al interactionto develop ral behaviornlarged and
eglitz, Knebel
(c)
nection to th
equences of
conseque
no measu
after shrestart
planned anticipateinspectionpair,quali
re-start quired
no planassumed
physical phennected. M
macro-scalen impacts cqualified cr of the plan
d still growi
& Tromm
5
hermal-
f a NPP.
ences
ures
hort time
restart ed (after n, re-ification)
not re-
t restart
enomena Moreover,
and are consider-computa-nt. ing com-
Stieglitz,
6
putationphenomtailed obut mucto a fueart exam
Thtor operthe powmethodsand the found apressurenumericwithin fimportasively v
O
conductMoreovof themdesign the reamance screenedone of tof theselimited lution, mands phistication of hydraully, this CFD. Brelativelmain lipressure(RPV) wnomenadecadesCFD, wcomputescale. Aquality nodal mapproacconnectputation
Knebel & Tro
nal capabilimena taking
n-line plantch more to el pin scale nmples are hihe thermal-ration, and h
wer and to ass are providcore as de
a-priori knowe vessel, cocal codes cfuel pellet, oant correlativalidated ag
Of course, fat exploring ver, by mea
m the impactmeasures
actor perfcan
d. Howevthe drawbace codes is th
spatial reswhich d
a more sated descrf the thermics. Naturis matched But, even ly small dike a reace veswould requa with an ads. One optiowhich is deped exactly
A similar apwithin the
methods; butch is mainlyted to a loopnal modelin
omm
Figu(botto
ties and theplace in NPt monitorinelaborate annot only steighlighted a-hydraulic trhence necesssess the feeded by 3D cepicted in fiwledge is reore and primontain largeover the gapons were deainst experi
fast computpotentially
ans t of on
for-be
ver, cks heir so-de-so-rip-
mal-ral-by
a do-ctor sel
uire such andequate reson for a corrpicted exemand then tr
pproach is uqualified pt this is on
y used for dp model bas
ng is the val
re 3: Transom right) an
e memory rPP than in t
ng by reducnd analyze eady state band discusseransport of ssitates a reedbacks betcoarse meshigure 2 andequired to dmary/seconde set of mop and on theerived fromimental data
ing code syy domains w
n enormouslolution thatrect transfer
mplarily in fansferred a
used from marameter racost of the
design verifised on a 1Didation. Esp
sfer from mnd then to r
resources althe past. Thed models with a high
but also in tred. mass and e
eliable fast rtween neutrh approach
d the pipingdescribe thedary systemodels and ce fuel rod su
m representaa before the
ystems allowith a redu
ly large numt it can be hr from micrfigure 3. Ths volumetri
meso- to maange of the considerab
fication. SucD coarse mepecially in t
micro-scale reactor scale
llow a morhese effortsto support
h local discrransients. S
energy is an running preronic and thhes to descrg is modellee individualm of a NPPcorrelations urface as w
ative experimey are used f
ow for parauced or eve
mber of celhardly solvro to macrohere, on a mic forces orcro scale. BCFD modely larger coch a CFD mesh. An essethe context
CFD (top r
e (left.).
e refined renot only al
operationalretization sa
Subsequently
essential feedictive codhermal hydraribe the reaced via 1D n
phenomenaP as denoted
to describewell as in the
ments and tfor safety as
ameterized en problem
lls to depictved within to scale provimicro-scale r interfacial By this apprels is by faromputationamodel for thential corneof the IAEA
right) to me
epresentatiollow for a ml safety in rafety margiy, some sta
eature in dades to flexibraulics. Fastctor pressurnodes.. Herena within thed in figure e the heat te fluid domthe codes arssessment o
computatiomatic safety
t all importthe next one
vides the coa all phenomtension to
roach the prr better thanal times, so he RPV caner-stone of tA, the OEC
eso scale
on of the more de-real-time ns down
ate of the
aily reac-bly adapt t running re vessel e, a pro-e reactor 2c. The
transport ains. All re exten-of NPPs.
ons or to margin.
tant phe-e or two arse grid mena are
a meso-rediction n for the that this
n then be the com-CD-NEA
Figure deboratbacks a
or internumericphysics plant dacomputetions aheights pump tducted OECD/Nthe figuidated ccapable tion as with a h
A
ing probthermaltion. Acontext ent. In ctor flooThe Doure 5 (totrates th
coupledN
safety pcombinaoften caes the sand the
5: Thermated water (bafterwards to
rnational ccal code patopics or c
ata and traned void frat three in a fuel
trip, which in the fra
NEA Bencure shows, tcurrent cod to depict well as tem
high degree
Another simblem is pos-hydraulic
A classical is a boron
case of an uoding with dppler feedbop) depicts he distributi
d with sub-cNodal methoparameters ation with talled best esstrongest che power ma
al-hydraulicblue) enterso a reductio
ollaborationackages. Thoupled neutnsients. Figraction distdifferent assembly has been
is devotexact neutions by meCarlo mech the theics is di
ded. Althouadditionally
computads, the prederably bet
9 such a comesult is showal distributi temperaturPWR FA [1
9: Inline-hydraulicsFA [15]- da
yond design
n contrast todesign acc
of Generatioreactor des
sis and adees. These ‘d reactor cospecific prons, see figu
pment has bng signals od classificatind in [16]. Ts caused ma
mena appearavior of largcts of non-codensation onavior of contmo- and fluim-liquid ints of passive
Firoofal
g new n cou-
simu-ed to utronic ans of thods, ermal-irectly ugh it y even ational ecision tter. In mputa-wn for ion of re of a 15]
e coupled computatioark blue=gu
n basis safe
o Gen-II reacidents are on-III plantsigns implicequate desig‘a-priori’ seontrol measuovisions e.gure 10. Remeen directedf intelligencion of passiThe expressainly by tem
red in connege pools of londensable
n containmetainment heid dynamicsteraction, etsafety syst
igure 8: Pinod ejection f fuel pin tel solution [1
Monte-Caon of the fuuide tube ch
ety (BDBA
actors measintegral p
s. What doecitly assumgn provisioetting of saures such a
g. for an impmarkably, thd mainly to ce to accomive safety ssion passivemperature g
ection with tiquid, gases on co
ent structureeat removals as well as tc. All thesems in vari
n based soluaccident (R
emperatures14].
arlo-neutronuel temperahannels.
A)
sures to copart of the es this mean
me the occurons to carryafety relateas control roproved eme
he focus ofsystems ac
mplish a safsystems to re means mgradients. Ithe innovati
ondensationes, systems, pressure dr
se effects emous advanc
ution of theREA). Comps for a pin-b
nics –ature of
pe with reactor
n? rrence of rey out preveed design pods and borergency coreemergency
cting by pasfe state of thrender a pla
mainly gravitIn addition,ive Gen-III
n heat transf
rop in differmerged intoed water co
Stieg
power distparison of t
based solutio
eactor statesentive and
pre-requisiterated water e cooling cacore coolin
sive means he plant in cant within aty or densit the followreactor con
fer,
rent geometo integratedooled nuclea
eglitz, Knebel
tribution (lethe temporaon compare
s exceedingmitigative
es doesn’t but additioapability inng systems and not nec
case of a Ba safe condity differenc
wing safety ncepts:
tric configurd engineeriar power pl
& Tromm
9
eft) during aal evolutioned to a nod-
g the de-accident abandon
onally al-BDBA-(ECCS)
cessarily DBA. A ition can ce driven
relevant
rations, ng solu-
lants. An
a n -
Stieglitz,
10
Figure
examsistin
Knebel & Tro
e 10: Safety
Fidoth
mple of the ng of
omm
y system (A
igure 11: Down situatioe EPR [18,
set of diffe
P 1000) [17
Different deons: in-vessright].
erent ECCS
7].
sign based sel retention
S systems e
safety provn strategy [1
employed w
wateplaccontage ity aal (Ptatioto nfigurIn afuncsystesteamof thdentegieary of thvessforefig.1EPRthe undecallefigur
visions to co17, left] and
within the A
core maker),
accumulaement),
coolant mtainment retank (IRWS
and passive re
PRHR) systonal forces name the mre 10.
a web-basedctionality ofems is illum line breahe occurrent with core ms are applieGen-III sy
he plant dessel retentionseen in t
11,left), whR is focusecorium in aerneath theed an exterre 11, right
ontrol core d core-catch
AP1000 des
ke-up-tanks
ators (for w
make-up frefueling waST) driven
esidual heattem based o
most import
d video in f the passiv
ustrated for ak (MSLB).nce of a sevemelt differeed in the ev
ystems. Onesigns follown strategy, the AP100hile others ed on spreaa dedicatede RPV, w
ernal core-c.
melt-
her of
ign con-
(borated
water re-
from in-ater stor-by grav-
t remov-on gravi-
tant, see
[17] the ve safety
a main . In case ere acci-ent strat-volution-e branch ws an in-
such as 00 (see
as the ading of
d domain which is catcher ,
Figure 1associate
Hvere accmeasureuncontrthe Helmlaboratistitute o
3.4 LR
ANPP depare PWnuclear In their electrici
BBDBA related rnearly aoperatioagemenmeasureby natiocant chaducers a
Aregardinefforts
12: Potentiaed R&D exp
However, thecident. In ces have to brolled hydromholtz-progons some o
of Technolo
R under de
After the finaployed belo
WR´s. The deelectricity mcontext, nu
ity generatioased on thesafety methrequiremen
all level as eonal safety nt of severe es deduced onal and intallenge to thand addition
Aside from tng nuclear sfrom manu
al containmperimental p
e safe confincase of a fabe implemeogen explosgram Nucleof the key sgy (KIT) as
velopment
ancial crisisongs to the ceployment meaning thauclear is seeon grid backe progress hods, the ponts into diffee.g. fundamand last buaccidents. from initia
ternational he individunally in the he economisafety since
ufactures an
ment phenomprograms at
nement of tailure of theented to enssions or moear Waste Devere accids depicted i
s in 2009 anclass of LR intention ofat the intenden to act askbone. in the scien
ower plant derent plant
mental core dut not least This previo
al design nesafety auth
ual companiformation oic aspects, e the Three nd utilities
ous itemizatecessitate ashorities, the ies, which rof strategic the industrMile Islan
s were unde
ring in a ca
represents on-vessel retinment inteconcrete intd Safety (NUmena are inv2.
ushima inci1GWe gros
ries is basede of the reacCO2-neutra
w-how to denslated the hich vary si
mber of hydrophy with rtion is by faside from vintegral LR
resulted bothalliances.
rial partnersd accidentsertaken in t
Stieg
se of a seve
only one asptention, dedgrity that mteraction (MUSAFE) anvestigated a
ident 2011, ss output and on a longctors is of thal energy so
escribe and hardened eignificantlyrodynamic espect to prar not exhauvalidation aR plant desih in the red
share fund. In the lastthe frame o
eglitz, Knebel
ere acciden
pect in casedicated contmay be affe
MCCI), etc.nd internatioat the Karls
the majoritnd out of thog-term utilizhe order of ource provi
validate Deconomic any from eachloops, desigrovisions austive, but
aspects the aign posed a
duction of N
damental knt decades, cof internati
& Tromm
11
nt [19] and
e of a se-tainment
fected by . Within onal col-sruhe In-
ty of the ose most zation of 60years.
iding the
DBA and nd safety
other at gn based nd man-since all approval a signifi-NPP pro-
now-how common onal co-
Stieglitz, Knebel & Tromm
12
operations and organizations such as the WANO (World Association of Nuclear Operators) aiming to get consensus on common safety design criteria for NPP, to share operation experi-ence collected in each country and in the IAEA e.g. the event notification reports, event anal-ysis reports and to foster mutual exchange of professionals and technical support for safety-relevant issues.
On the opposite side governments and technical survey organizations (TSO) established an international cooperation on a worldwide basis as e.g. through the IAEA (International Atomic Energy Agency). The regulatory authorities of the Western European countries have create the WENRA association devoted to intensify the cooperation and work out standard-ized regulations and safety requirements for the licensing of nuclear power plants.
In addition, a vast bandwidth of worldwide collaborations on dedicated topics exit with-in the nuclear community such as the Global Nuclear Energy Partnership (GNEP), Interna-tional Framework for Nuclear Energy Cooperation (IFNEC), Multinational Design Evaluation Program (MDEP), the Contact Expert Group (CEG) and in Europe for example the European Atomic Energy Community (EURATOM), which themselves are complemented often by bilateral agreements on safety standards and best practice guidelines.
As result of these international activities and the beneficial interaction of manufactures and regulators, new reactors of Gen-III have been developed taking profit of the extensive operational experience of hundreds of NPP of Gen-II, of the advances in nuclear technology, material sciences, computer codes, etc. and considering the overall safety requirements con-tinuously updated and published by the IAEA that reflects the state-of-the –art of science and technology. Hereafter, selected reactor designs without claiming for completeness are briefly described.
The European Pressurized water Reactor (EPR), depicted in Figure 13a, is based on a 4 loop evolutionary PWR design evolving from both the N4 (France) and the Konvoi (Germa-ny) design; its rated power is about 1600 MWel and it consists of 4 train active safety systems, a strong double containment design (primary containment designed for low pressure core melt, Corium spraying area, shield building), protection of the plant against commercial air-plane crash by protected buildings (containment, fuel building, part of the safeguard build-ings) and by physical separation (part of the safeguard buildings, diesels, …). The large core (241 FA) allows for a power upgrade, an economical fuel management allowing for 50% mixed oxide (MOX) core loading and long cycles up to 24 months [20]. Another concept currently deployed successfully by KEPCO Korea is the APR1400, figure 13b. It is also PWR with a rated power around 1400 MWel using a compact core. This reactor design originated from the CE80+ developed by Combustion Engineering in the 80’s (certified in USA in 1996). It is a 2-loop design with 2 steam-generators and 4 pumps having 2-train active safety systems and 4 independent mechanical trains for safety injection systems. The containment consists of a single concrete containment with steel liner with a high re-sistance against earthquakes. In contrast to the EPR, the severe accident management strategy focuses on an in-vessel Corium retention through external reactor vessel cooling by means of water provided from the IRWST and additionally a boric acid make-up pump [21]. Among these two PWR designs shown here, several other PWR are currently erected as the AES fam-ily (Russia), AP1000 (Westinghouse-Toshiba) and others are certified as the ATMEA (MHI-AREVA) and the APWR 1000 (MHI). The interest in light water boiling water reactors (BWR) is considerable smaller than in PWR´s and aside the already licensed plant types such as the AB1600 (Toshiba), ESBWR (General Electric) and KERENA (AREVA), the Advanced Boiling Water Reactor (ABWR from Hitachi-General Electric) is currently erected. The safety philosophy of such reactors regarding the control of severe accidents is similar to the one of a PWR plant, while marginal differences naturally arise with respect to the operational safety due to the diverging principle.
Figur1=douarea aKEPC
3.5 SM
The targprocess principlfor som Syste comp modu use o reduc high There isfor a deploymis theirtentiallymore rsafety formancusing sified aand pasafety tems dutheir volumetpower dty. Aone exaof an currentlbeing ed in A
re 13: (a) Cuble walled and IRWSTCO and (c) p
FisatemsyA=
MR technolo
get for the Sheat and w
le higher thame countries
em simplifipactness, ularity allowof cheaper action of the availability
s a vast variSMR
ment r po-y robust
per-ce by impli-active assive
sys-ue to lower tric densi-
As ample SMR
ly erect-
Argen-
Cut throughd containmeT, 4=4 trainprimary circ
igure 14: (afety system,3=residu
ystem, 5=p=core, B=st
ogies under
SMR deploywater desalian the one due to the fcation,
wing for uprand more stae amount ofy and short iety on liter
h the nucleant, 2= contan safe guarcuit [21].
a) integral ems: 1=firal heat rem
pressure suteam genera
r developm
yment doesination. EveLR´s, the M
following p
rate the planandardized f used parts,outage time
rature availa
ar island ofainment herd system.
core designrst shutdow
moval systemuppression ators, C=rea
ment
s not only foen though MSR’s repr
peculiarities
nt on one siconstructio, and es. able on SM
f the EPR at removal b.) plant cu
n of the CAwn systemm primary pool, 6=c
actor buildin
ocus on elec the capital
resent an att:
ite by deplon technique
MR’s, [22-2
Stieg
and safety system, 3=ut-away of
AREM 25 rm, 2=secon
system, 4=containmentng.
ctricity prodl cost per intractive alte
oying multipes,
8]. One sup
eglitz, Knebel
systems in= corium sprf the APR1
reactor. CAnd shutdo
=emergency t, 7=safety
duction but nstalled MWernative to t
ple units,
perior optio
& Tromm
13
nstalled. reading 400 by
AREM 25 wn sys-injection
y valves,
also on Wh is in the LR’s
on voting
Stieglitz,
14
tina is tPWR banal preswhich thure 14a.of 3 dayan in-vetrol. The
3.6 Nu
Inthe majoed to thsequencAs mennot onlyduring onides anclosed aconsecu
WFi
water retion of burned active fdenum was e.g. PEach ye(LLW) diate-levtive wAdditioimately high-lev(HLW) used fuas waste[29]. Athe wasLLW tyer 5.9%ILW. AHLW 0.1% about 95
ALLW an25 tons)lation if
Knebel & Tro
the CAREased entirelssure of 12he steam ge. The severeys without aessel coriume CAREM p
uclear waste
n the publicor drawback
he time scaleces to be expntioned in §2y with respoperation annd finally thand, moreoutive nuclea
Which amounigure 15 sheactor after the FA sti
down to 0.7fission prodwith a shor
Pu, Np, Amear, nuclear
and intermvel radio
waste (ILWnally, appr
104m3 vel wa
includuel designae are produc
About 94% ste volumeype and ano% belongs Although is less thit conta
5% of the toA 1000 MW
nd ILW wa) of used fuf it is entire
omm
Figudurin
EM 25 (Cenly on natura2.25MPa. Tenerators are accident pany intervenm retention aplant layout
e - Origin –
c perceptionk of nucleares ensuringpected if the2 of the Atopect to capind fuel manheir decommver publica
ar installationt of masseows the cha3 full poweill consists 73% and a m
ducts such art decay tim
m and Curiumpower gene
me-oac-W). rox-
of aste ding ated ced
of e is oth-
to the han ains otal invento
Wel light waaste per yearuel per yearely treated a
ure 15: Fueng 3 full po
ntral ARgenal convectio
The CAREMre integratedprovisions antion by autand passivet is illustrat
–volume an
n, the nuclear energy uti
g a safe confe confineme
omic Law, ttal return tinagement inmissioning ally accepteons to be opees and volumange of the er years (fpy
of U238(9minor fractias Xenon or
me. Driver fom generatederation faci
ory of radioaater reactorr. By fissio. This requias nuclear w
el compositwer year op
ntina de Eleon and self-M reactor rd within the
are based ontonomous se autocatalyted in figure
nd managem
ar waste issilization. Thfinement buent is lost othe nuclear ime but alsncluding lonand dispos
ed waste maerated. mes are inv
e fuel compoy) with a m94.5%), whion of U236.r Cesium b
for the majod by neutronilities world
activity [30(LWR) wi
on and its prires about 7waste. In ca
tion changeperation up
ementos M-pressurizedrepresents ae reactor prn preventionystems and
ytic recombe 14b.
ment strate
sue and its he major aput also the c
or unauthorienergy utiliso regardingng-lived fisal. The latteanagement
volved ? osition of 1
mean burn-uphich is unaf About 3.41
but also valuor public con capture ofdwide gener
]. ill generate roducts a N
75 m3 disposase of a repr
of a fresh to 33GWd/
odulares), wd primary sya so-called essure vess
n by ensurinmitigation
iners (PAR
egies
managemenpprehensionconcerns abzed access tization is a g the relatsion producer mentionestrategy co
7x17 Fuel p of 33GWhffected, wh1% is a set uable const
oncern are thf Uranium. rate about 2
b approximNPP produce
sal volume rocessing of
17x17 LW/t.
which is a ystem with integral de
sel, as showng long grac
measures tR) for hydrog
nt are concns are not onbout radiototo the dispogeneration
ted waste gcts and Mined aspects ronsisting of
assembly oh/t. The ma
hile the fissof are highl
tituents likehe Minor A
.105m3 of lo
mately 200es about 10following ef the spent
WR FA
27MWe a nomi-
esign, in wn in fig-ce period to enable gen con-
ceived as nly relat-oxic con-osal site .
contract generated nor Acti-require a f a set of
of a light ajor frac-sile U235 ly radio-
e Molyb-Actinides
ow-level
-350 m3 m3 (20-encapsu-fuel, the
Stieglitz, Knebel & Tromm
15
volume reduces dependent on the technology used by a factor of 10 to 30 (theoretically sub-stantially more) meaning that about 3-7 m3 of vitrified waste in form of glass are the subject of nuclear waste disposal. Due to the heat generation, the glass pellets require about 28 m3 disposal volume in a dedicated canister [29]. The technological progress e.g. volume reduc-tion techniques, abatement technologies, etc. as well as optimization of work flows, a sub-stantial minimization of waste was achieved in the recent decades. Nonetheless, nuclear utili-zation poses a societal challenge since it demands a consistent and enduring waste manage-ment policy to ensure environmentally sound solutions preventing any hazard to both work-ers and general public. Even, abandoning the nuclear energy option for electricity generation, there is a need to preserve the knowledge related to ionizing radiation, radiation physics, radi-oisotopes, etc. due to the large application of nuclear technology in areas not related with electricity generation such as medical diagnostic, automation and control, water treatment, etc. . Moreover, one should relate the numbers of NPP waste production to that of a coal fired power plant of the same size, which produces aside from CO2 about 4.105tons ash a year con-taining heavy metals such as As, Cd, Hg, Pb or Thallium [31], requiring an adequate storage.
The nuclear waste in Germany is continuously monitored by the Bundesministerium für Strahlenschutz (BfS) [32]. The expected amount of nuclear waste to be conditioned in the future in intermediate and final repository is also well known and any time quantifiable.
Summarizing one can state that irrespective of societal decision taken, nuclear energy utilization requires reprocessing, conditioning and transportation to a safe confinement. All these processes are oversight by the regulatory body according to the national nuclear regula-tions. Regarding the waste disposal. there are several options feasible either in the temporal and the spatial frame, necessitating societal acceptance and simultaneously matching safety constraints. Regarding the temporal time window, the choice is at first an intermediate storage deciding in request further re-processing options or an ultimate solution by vitrification of the entire inventory. With respect to the spatial solution options, there are on the one hand near soil storage solutions but requiring as drawback permanent access control and confinement integrity and on the other hand deep underground disposals with or without an access option demanding also an analysis for a long term safe confinement.
3.7 Transmutation and Generation-IV
In the view of the nuclear waste generation and their interrelated issues, the utilization solely of light water reactors will lead to an accumulation of the minor actinides (MA) such as Americium, Curium, Neptunium and also Plutonium. The energy released by the fission of Plutonium can be recovered by means of a fast spectrum reactor allowing for a sustainable use of uranium resources. This potential has been identified quite early several decades ago. In May 2001 under the lead of the United States Department of Energy, the Generation IV international forum (GIF) has been founded. The top level requirements postulated by GIF for the Gen-IV reactors are: sustainability (meaning transmutation capability), enhanced econom-ics (lower life cycle costs), improved safety (low probability or even absence of any off-site emergency measures) and non-proliferation. This GIF initiative currently consists of 12 coun-tries. The EU is involved by cooperations within international frameworks such as the IAEA's International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO) or within the Europe the Sustainable Nuclear Energy Technology Platform (SNETP).
One of the major aspects for the fast spectrum reactors is their transmutation capability. Transmutation hereby describes the transfer of radionuclides by neutron induced fission or neutron capture into another element as illustrated in figure 16. By dedicated design measures, fast spectrum reactor systems are therefore able either to breed fissile material or to destruct fissile minor actinides. One of the drawbacks of the fast reactor systems is that they require a
Stieglitz,
16
Figur(FP=ftation)
dedicateplant, war logist
Fi
tial fueand tranfigure causes presencthat a fvented. option wand addand also Omany taconductonly tecand the only natergy utient of thone centrum rea
Knebel & Tro
re 17: Potefission prod).
ed fuel cyclwhich intrintics system.
igure 17 deel cycle incnsmutation.17, each closses and e of a temfinal reposiHowever, a
would requiditionally it o the time s
Of course, thargeting forted in the cochnological
boundary ctional scenailization andhe P&T sce
ntury enterpactors.
omm
ential fuel duct, TRU=
le incorporasic implies .
epicts such cluding par As clearlyconversion
naturally mporary stoitory cannotanticipatingire a substanwill consid
scales for mhe implemer an exit ofontext of thaspects or p
conditions tarios but ald countries enario antic
prise. Manda
cycle requTransuranic
ating a dedia nucle-
a poten-rtitioning y seen in
process also the
orage so t be pre-
g such an ntially reducderably redumandatory mntation of a
f nuclear cahe German Apotential hato be set or lso mixed oexiting nuc
cipated, a fuatory for su
Figure 16fast neutro
uired for trc elements,
icated fuel
ced volumeuce the rad
monitoring a “new fuelauses conceAcademy oazards inclu
at least to options consclear energyull destructiuch P& T o
6: Transmutons (top) or
ransmutatioP&T=Part
fabrication
e of temporadioactive inv
[33]. l cycle “ esrns. Thereff Sciences (
uding man mbe preparedsidering co
y generationion of the l
option is in
tation of nuby neutron
on of minoitioning and
and specifi
ary storage ventory, the
pecially in fore, a detai(ACATECH
made but alsd. One majoountries conn have beenong lived fiany case th
uclei by fisscapture (bo
or actinidesd Transmu-
fic fuel repr
and final ree total radio
countries liled study hH) investigaso societal cor aspect isntinuing nucn studied. Infission prodhe use of fa
sion of ottom).
s -
ocessing
epository otoxicity
ike Ger-has been ating not concerns that not clear en-ndepend-ducts is a ast spec-
4 Fast
Nearly tors matmature (LFR) since atfour decpublic asystemstion to pand fuecross-se18a. Toexceed celeratotems (AMA caThese Awhich nent exMYRRH[33] asub-critwhich triggerebeam The proin the ttron soure 18bthe corthe tarcritical power dof a losor a bea
5 Sum
Nuclearductionsued in ensuringlarge scin a disconsidenot onlyhaviors formancinterest last two
spectrum g
all reactor ttching to a in this concurrently c
t least for thcades in sevas critical sis to produceproduce (“bl compositi
ectional cut o allow for a2-5%. In an
or driven sADS), in whan be burnADS Systemmost prom
xample is HA reacare so-caltical reactoare externa
ed by a proaccelerat
otons genertarget the nurce, see fb. By desire enveloprget is su
so that decays in css of the beam shut-dow
marizing c
r energy uti, mainly gnumerous
g fossil fuecaled light wspatched orgrably from y for the deand measur
ce gain are holders, as
o decades. Ir
Figuand eutecCEN
generation
types considlarge extenntext are soonsidered ihe SFR a cveral countince these r
e as much fibreed”) a Pluion means, as well as
a high core ny case SFRsys-hich ned. ms, mi-the
ctor lled ors, ally
oton tor. rate
neu-fig-ign,
ping ub-the
case eam wn.
comments
ilization repenerated bycountries m
el independwater reactoganized grithe scientif
esign basis res now alrechanges in
s science, inrrespective
ure 18: (a) Score cross-
ctic PbBi cN, Belgium.
IV reactor
dered in thed the requirodium-coolen the world
considerableries worldwreactors havissile materiutonium stoSFR are alphotographsafety simi
R-reactors a
presents stily generationmainly in A
dence. As a rs of the genid. The devfic progressbut also wieady integrathe safety c
ndustry, tecof the furth
Sodium coo-section. (bcooled sub-
rs
e context ofrements posed fast readwide devele operationwide. The reve been in tials as they ockpile durilso able to ths of the ereilar to LWRare fast “cri
ll a substann II power pAsia as a lo
consequenneration III
velopment os especiallyith respect tated in the dculture by thchnical survher energy u
oled fast reab) Schematicritical AD
f Gen-IV instulated in tctors (SFRlopment as al experieneputation othe past eithconsume (s
ing the coldtransmute lection of a
R´s the amouitical” syste
tial part of plants. Nucong term elnce, most reI rather thanof these geny with respeto the beyodesign. Thehe internati
vey organizutilization n
Stieg
actor currenical cross-s
DS reactor d
nitiative are he Gen-IV ) or lead cto be the vce has beenf the SFR iher designesustainabilitd war. But, blong-living SFR in Indunt of MA
ems in contr
the worldwclear energylectricity preactors currn SMR´s whneration III ect to their nd design b
e fundamentonalization ations and uclear is a g
eglitz, Knebel
ntly erected sectional cudeveloped a
fast spectruroadmap. T
cooled fast viable reacton gained inis considereed to as equty) or even by dedicatefission pro
dia shows thin the fuel rast to so-ca
wide electricy productionroduction brently deplohich would
reactors besafety perfbasis accidets of this sa
n through allgovernmengeneration c
& Tromm
17
in India
ut of an at SCK-
um reac-The most
reactors or types,
n the last ed in the uilibrium in direc-d design ducts. A he figure shall not alled ac-
city pro-n is pur-
backbone oyed are fit better enefitted
formance ental be-fety per-l nuclear
nts in the contract.
Stieglitz, Knebel & Tromm
18
Hereby, the waste management, the processing and the logistics play an essential role, de-manding a continuous monitoring and a sensible long-term oriented technological planning complemented by public acceptance. The amount of nuclear waste and its volume is small compared to the ones of conventional fossil based energies. In this context, partitioning and transmutation in fast spectrum reactors offers a credible option to minimize the burden on future generation either by national efforts or integrated in a regional context. Independent of the societal decision on the future use of nuclear fission for energy production, the develop-ment of education in nuclear engineering must persist of vital interest to an industrialized country like Germany to assure not only a credible nuclear safety assessment capability but also further investigations to tackle the technical and scientific challenges related to the final disposal of nuclear waste, which is still far ahead of us. Acknowledgement
The authors thank for the support of numerous colleagues of the program nuclear safety of the Karls-ruhe Institute of Technology for providing material.
6 Literatur
[1] http://www.iaea.org/PRIS/WorldStatistics/WorldTrendinElectricalProduction.aspx; on 6th March 2014. [2] http://world-nuclear.org/Information-Library/ on 6th March 2014. [3] http://ec.europa.eu/energy/nuclear/index_en.htm on 10th March 2014 [4] Szynol, K., The German Energiewende from a central European perspective, ATW-Int. J. Nuc. Power,
bareEnergien/Photovoltaik/DatenMeldgn_EEG-VergSaetze/DatenMeldgn_EEG-VergSaetze_node.html . 5th March 2014.
[6] M.D. Carelli, P. Garrone, G. Locatelli, M. Mancini, C. Mycoff, P. Trucco, M.E. Ricotti, 2010, Economic features of integral, modular, small-to-medium size reactors. Prog. in Nuc. Energy 52(4), 403–414
[7] IAEA –TECDOC-1652, 2010, Small Reactors without On-site Refuelling: Neutronic Characteristics, Emergency Planning and Development Scenarios, ISBN 978-92-0-106810-1.
[8] IAEA-Nuclear Energy Series, 2009, Design Features to Achieve Defence in Depth in Small and Medium Sized Reactors, STI/PUB/1399; ISBN 978–92–0–104209–5.
[9] European Utility requirements (EUR), 2014, http://www.europeanutilityrequirements.org/Welcome.aspx and documents therein.
[10] WENRA, 2014, Report on Safety of new NPP designs; published by Reactor Harmonisation Working Group (RHWG), Aug. 28, 2013, 11:17 a.m.
[11] IAEA-Safety Standard Series, 2009, NS-R-1- Safety of nuclear power plants: design, updates to find on http://www-pub.iaea.org/mtcd/publications/ResultsPageSSS.asp
[12] Perez-Manes, J., 2013, Development of CFD Thermal Hydraulics and Neutron Kinetics Coupling Method-ologies for the Prediction of Local Safety Parameters for Light Water Reactors, PhD-Thesis, KIT
[13] M. Calleja, J. Jimenez, U. Imke, V. Sanchez, R. Stieglitz, José J. Herrero, R. Macián;Implementation of hybrid simulation schemes in COBAYA3/SUBCHANFLOW coupled codes for the efficient direct predic-tion of local safety parameters Review Article. Annals of Nuclear Energy, Volume 70, August 2014, Pages 216-229.
[14] Ivanov, A., current PhD at KIT [15] A. Ivanov, V. Sanchez, R. Stieglitz, K. Ivanov, 2014, Internal multi-scale multi-physics coupled system for
high fidelity simulation of light water reactors, Annals of Nuclear Energy, 66,104–112. [16] IAEA, 2009, Passive Safety Systems and Natural Circulation in Water Cooled Nuclear Power Plants,
IAEA-TECDOC-1624, ISBN 978–92–0–111309–2. [17] http://ap1000.westinghousenuclear.com/ap1000_psrs_pccs.html and documents cited there on march 25th
2014. [18] W. Kröger, 2011, Safety of nuclear power plants, ETH-Spring-Seminar. [19] Tsvetkov, 2011, ISBN 978-953-307-507-5 [20] AREVA, 2014, http://www.areva.com/EN/operations-1740/epr-overview-built-for-safety.html, download
on 27th March 2014. [21] Korea Electric Power Company, Overseas Nuclear Projects Development Department, 2014, APR-1400
Design Description, available @ www.kepco.co.kr / www.apr1400.com.
Stieglitz, Knebel & Tromm
19
[22] OECD, 2011, Current Status, Technical Feasibility and Economics of Small Nuclear Reactors – OECD/NEA – Nuclear Development – June 2011
[23] IAEA, 2005, Status of innovative small and medium sized reactor designs. IAEA TECDOC-1485. [24] Status of small and medium Sized Reactors Designs – September 2011– A supplement to the AIEA Ad-
vanced Reactors Information System (ARIS) - http:aris.iaea.org [25] K. Hibi, H.Ono, T. Kanagawa, 2004, Integrated modular water reactor (IMR) design –- Nuc. Engng. Des.
Design 230, 253–266. [26] The SMART Reactor - 4th Annual Asian-Pacific Nuclear Energy Forum - 2010. 6. 18-19 [27] VBER-300 (VBER-300) - IAEA -6 Status Report for Advanced Nuclear Reactor Designs - Report 66 [28] Westinghouse Small Modular Reactor Nuclear – Proceedings of ICAPP’12 – papers 12248, 12253, 12250
and 12157. [29] IAEA,2014, http://www.iaea.org/Publications/Factsheets/English/manradwa.html, called 29th March 2014. [30] Department of Energy and Climate Change (DECC) and the Nuclear Decommissioning Authority (NDA),
Radioactive Wastes in the UK: A Summary of the 2010 Inventory. [31] O. Rentz; Ch. Martel, 1998, Analyse der Schwermetallströme in Steinkohlefeuerungen– Einfluss der Koh-
lesorte und des Lastzustandes, Förderkennzeichen: PEF 4 96 001 [32] Bundesministerium für Strahlenschutz, 2012, http://www.bfs.de/de/endlager/abfaelle/abfallbestand.html
and related pages . [33] O. Renn, 2013, Partitionierung und Transmutation - Forschung – Entwicklung – Gesellschaftliche Implika-
tionen, Projektbericht vom 22.10.201 3 Förderkennzeichen GESI 2012A und GESI2012B Bundesministeri-um für Bildung und Forschung (BMBF) und Bundesministerium für Wirtschaft und Technologie (BMWi).
[34] MYRRHA, 2014, MYRRHA- Multi-purpose hybrid research reactor for high-tech applications. http://myrrha.sckcen.be/ and related pages taken 31st March 2014.
