Fromfieldtofactory—TakingadvantageofshopmanufacturingforthepebblebedmodularreactorOriginalResearchArticle

Themoveofnuclearplantconstructionfromthefieldtothefactoryforsmall,advancedpebblebedmodularreactor(PBMR)designshassignificantbenefitscomparedtotraditionallightwaterreactor(LWR)fieldorienteddesigns.Theuseofmodularfactoryconstructiontechniqueshasagrowingeconomicbenefitovertimethroughwell-establishedprocesslearningapplications. ThispaperaddressesthebasicPBMRdesignobjectivesandcommercializationmodelthatdrivethisapproach;providesabrieftechnicaldescriptionofthePBMRdesignandlayoutwithrepresentativeCADviewsanddiscussesderivedfiguresofmerithighlightingtherelativesimplicityofPBMRcomparedtoamodernLWR.ThediscussionemphasizesthatmoreofPBMRcanbebuiltinthefactoryduetothesimpledesignofadirectheliumBraytoncyclecomparedtoanindirectLWRsteamcyclewithitsassociatedequipment.ForthePBMRdesigntherearefewerandlesscumbersomeauxiliaryandsafetysystemswiththeirattendantsupportrequirements. Additionally,thelaborforceeconomicefficiencyfornuclearprojectsisbetterinthefactorythaninthefield,includingconsiderationoflaborcostsandnuclearqualityprograms.Industriallearningisbetterinthefactorybecauseofthemorecontrolledenvironment,mechanizationoptimizationopportunitiesandbecauseofthemorestablelaborforcecomparedtothefield.Supplychainbenefitsaremorereadilyachievablewithstrategiccontractsformodulesuppliers.Althoughbuildinganuclearpowerplantisnotatypicalhighvolumemanufacturingprocess,forthePBMR-typeofplant,withitshighdegreeofstandardizationandrelativelysmall,simplifieddesign,theshifttofactoryworkhasasignificantimpactonoverallprojectcostduetoearlieridentificationandbettercoordinationofparallelconstructionpaths.ThisisinstarkcontrasttotheconstructionofalargeLWRinthepast.Finally,thePBMRmodularplantconceptcontinuesattheoverallplantlevelwhereuptoeightunitscanbeintegratedintoonesiteonaplotplansmallerthananequivalentlargeLWRwithsimilarelectricoutput. Thebottomlineisthatschedulesareshorter,theabsolutecostislower,andbotharemorepredictable.Theseadvantageswillyieldahigherreturntoclientsandinvestors