Advanced LWRsJacopo BuongiornoAssociate Professor of Nuclear Science and Engineering22.06: Engineering of Nuclear Systems--Outline Outline Performance goals for near-term advanced LWRs Technical features of advanced LWRs:Technical features of advanced LWRs: - US-EPR (Evolutionary Pressurized Reactor) -US-APWR (Advanced Pressurized Water Reactor) US APWR (Advanced Pressurized Water Reactor) - AP1000 (Advanced Passive 1000) -ABWR ((Advanced BWR)) - ESBWR (Economic Simplified BWR) Summaryy of common characteristics Conclusions 2Nuclear Reactor Timeline 3Mission/Goals for Advanced LWRs Mission/Goals for Advanced LWRs Baseload generation of electricity (hydrogen is not emphasized) Improved economics. Targets: - Increased plant design life (60 years) -Shorter construction schedule (36 months*) Shorter construction schedule (36 months ) - Low overnight capital cost ($1000/kWe** for NOAK plant) - Low O&M cost of electricity ( 1¢/kWh) * First concrete to fuel loading (does not include site excavation and pre-service testing) ** Unrealistic target set in early 2000s. Current contracts in Europe, China and US have overnight capital costs >$3000/kWe ImprovedImproved safety and reliabilitysafety and reliability - Reduced need for operator action - Expected to beat NRC goal of CDF<10-4/yr RRedduced large rellease probbabilitbility-d l - More redundancy or passive safety 4UU.SS. NRCNRC CCertifitificatition off AdAdvancedd LLWRWRs DesignApplicantTypeStatusDesignApplicantTypeStatusAP1000 Westinghouse-ToshibaAdvanced Passive PWR1100 MWeCertified, amendment under reviewreviewABWR GE-Hitachi Advanced BWR1350 MWeCertified, Constructed in Japan/TaiwanESBWRGE-HitachiAdvanced Passive BWRUnder reviewESBWRGE-HitachiAdvanced Passive BWR1550 MWeUnder reviewUS-EPR AREVA Advanced PWR1600 MWeUnder reviewUSAPWRMit bi hiAd d PWRUd iUS-APWRMitsubishiAdvanced PWR1700 MWeUnder reviewU.S. Economic Pressurized Reactor (US-EPR) Reactor (US EPR) bAby Areva 6US EPR Overview-USEPR Overview1600 MWe PWRTypical PWR operatingTypical PWR operating conditions in primary system, pressure, temperatures linear powertemperatures, linear power, etc. 4 loopsHi h i SGHigher pressure in SGs results in somewhat higher efficiency (35% net)Safety systems are activeHigh redundancy7US EPR ParametersUS-EPR ParametersParameter Current 4-loop PWR EPR Design life yrs4060Design life, yrs 40 60Net electric output, MWe 1100 1600 Reactor power, MWt 3411 4500 Plant efficiency, % 32.2 35.6y,Cold/hot leg temperature, C 292/325 296/329 Reactor pressure, MPa 15.5 15.5 Total RCS volume, m3 350 460 Number of fuel assemblies 193 241Type of fuel assemblies 17x17 17x17 Active length, m 3.66 4.20 Li kW/18 316 4Linear power, kW/m18.316.4Control rods 53 89 Steam pressure, MPa 6.7 7.7 Radial reflectorNoYesRadial reflector No YesSG secondary inventory, ton 46 83US-EPR Safetyy Four identical diesel- driven trains, each 100%, provide redundancy for maintenance or single- failure criterion (N+2) Physical separation against internal hazards (e.g. fire) Shield building extends airplane crash and external explosion external explosion protection to two safeguard buildings and fuel building (blue walls) 9US-EPR Safety ( ) 2y( )U.S. NRCSafety GoalCurrent U.S.LWR PlantsEPRI UtilityRequirement1 x 10-45 x 10-51 x 10-54 x 10-7Core Damage Frequency Per YearCore Damage Frequency Per Year10US-EPR Containment Inner wall pre-stressed ih lli concrete with steel liner Outer wall reinforced concrete Protection against airplaneProtection against airplane crash Protection against externalexplosionsexplosions Annulus sub-atmospheric and filtered to reduce radioisotope releaserelease 11US-EPR Severe AccidentsMitigationUS EPR Severe Accidents MitigationIRWSTCorium Spreading AreaEx-vessel core catcher concept (passive)-Molten core is assumed to breach vessel- Molten core flows into spreading area and isspreading area and is cooled by IRWST water- Hydrogen recombiners ensure no detonation within container12EPR is beingg built nowOlkiluoto – September 2009Taishan – September 2009Olkiluoto 3 (Finland) - construction start 2004Flamanville 3 (France) - construction start 2007Taishan (China) – construction start 2008Flamanville – October 2009© source unknown. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse.U.S. Advanced PWR (US-APWR) by Mitsubishi by Mitsubishi 14US-APWR Overview (fundamentally similar to US-EPR) 1700 MWe PWR1700 MWe PWR Typical PWR operating conditions in primary system, pressure, temperatures etc temperatures, etc. Long (14 ft.) fuel assemblies with reduced power density for 24 months operation months operation 4 loops High efficiency turbine (70" blades) results in >35% thermal efficiency results in >35% thermal efficiency of plant RPV with no bottom penetrations Safety systems are active with highSafety systems are active with high redundancy 15US-APWR Safetyy HP 16US-APWR Safety (2)y( ) Accumulator design with flow damper eliminates need for active high-pressure injection system SSevere accid identts miti itigati tion bbasedd on core-cathtcher conceptt similar to US-EPR 17tAdvanced Passive 1000 (AP1000) (AP1000) bW i Thib by Westinghhouse-Toshiba 18AP1000 OverviewAP1000 Overview 1100 MWe PWR Typypical PWR opperatingg conditions, pressure, temperature, flow rates, linear power, etc. RPV with no bottom penetrations 2 loops, 2 SGs 4 recirculation pumps (canned motor pumps, no shaft seals) Large pressurizer  50% larger than operating plants All safety-grade systems are passive 19 Courtesy of Westinghouse. Used with permission.AP1000 Passive Core Cooling SystemAP1000 Passive Core Cooling SystemPRHR HXPRHR HX Natural circ. heat removalPassive Safety Injection Core Makeup Tanks (CMT)Core Makeup Tanks (CMT) Full press, natural circ. inject  Replaces HPCI pumpsAccumulatorsAccumulators  Kick in at intermediate pressure IRWST Injection Low press (replaces LPCI pumps)Low press (replaces LPCI pumps) Automatic RCS Depressurization20Courtesy of Westinghouse. Used with permission.AP1000 Passive Containment CoolinggySystem 21 Courtesy of Westinghouse. Used with permission.AP1000 Severe Accidents Mitigation Core-Concrete Interaction  In-Vessel Retention (IVR) / ex-vessel coolingcooling  Means of cooling damaged core REACTOR VESSEL  Tests and analysis of IVR reviewed by U S NRC U.S. NRC REACTOR