Next and Last Generation of Nuclear Power Plants Paul Howarth Exec Director, Dalton Nuclear Institute IMechE Branch Meeting Jan 2009
Order of Service Introduction to status of advanced systems The 3 contending designs EPR AP1000 ESBWR Way Forward
Mass Balance for Helium
Nuclear Fission Reaction
Energy Released from Fission U235 + n fission + 2 or 3 n + 200 MeV 165 MeV 7 MeV 6 MeV 7 MeV 6 MeV 9 MeV 200 MeV ~ kinetic energy of fission products ~ gamma rays ~ kinetic energy of the neutrons ~ energy from fission products ~ gamma rays from fission products ~ anti-neutrinos from fission products Energy release is equivalent to 80 million kj/g 235U!! Or 4 million x energy in chocolate Or 2 million x energy in Natural Gas.
Controlled Nuclear Fission
Ceramic Fuel Pellets
J A2 Standard Fuel Assembly
Slide 8 J A2 Paul Howarth, 13/08/2007
How a Fission Reactor Works
Nuclear is alive and well around the World Provides 16% of world s electricity 440 nuclear reactors operating worldwide More than 11,000 reactor-years of operating experience 10+ new plants connected since 2004 27 new plants under construction In Europe: Some new build taking place and other countries are revising energy policy China has placed an order with Westinghouse for new AP1000s Middle East, Far East, South American and Australasian counties
Issues Surrounding Nuclear Low Carbon Technology Security of supply Safety Base load Generation Economics Waste Management
Modern nuclear plant costs are understood and are competitive Typical costs are in range 30-40/MWh All costs are accounted for.. 41% 17% 2% 25% Capital Decommissioning Operations and Maintenance Fuel Spent Fuel Management 2% 13% Financing
Building to time and cost 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 Planned schedule Yonggwang 3 Actual Yonggwang 4 Ulchin3 Ulchin 4 Yonggwang 5 Yonggwang 6
Expectations Net for Capacity load-factors Factors are high! 100.0 90.0 80.0 70.0 60.0 50.0 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 Source: WANO and Nuclear Energy Institute US world
Load Factors for new proto-type plants Average Load Factor Over Last Decade of Operation 100 90 80 93 82 Average Load Factor (%) 70 60 50 40 30 37 27 24 62 63 55 20 14 10 8 0 Emsland world commercial reactors Superphenix Phenix Dounreay FR PFR Dounreay Windscale AGR Winfrith SGHWR Julich AVR Fort St Vrain HTR
Generation III Technology
Current Nuclear Options Reactor Design Type Country of Origin Lead Developer ABWR BWR US Japan GE, Toshiba, Hitachi CANDU-6 PHWR Canada AECL VVER-91/99 PWR Russia Atomstroyexport AHWR PHWR India Nuclear Power Corporation of India APR-1400 PWR Korea, US Kepco APWR PWR Japan Westinghouse & Mitsubishi EPR PWR France, Germany Framatome ANP AP1000 PWR US Westinghouse SWR BWR France, Germany Framatome-ANP ESBWR BWR US GE ACR PHWR Canada AECL
AECL - ACR-1000 AREVA- UK EPR GE-Hitachi - ESBWR Westinghouse - AP1000
Areva European Pressurised Water Reactor
The European Pressurised-water Reactor Design
The European Pressurised-water Reactor Design Technology based on existing N4 and Konvoi reactors in France and Germany under construction in Finland, French demonstrator ordered Safety Features Increased Safety Margins Greater volumes to reduce transients enhanced protection against aircraft impact and earthquakes Construction Currently being built in Finland and France
EPR characteristics Thermal power 4300 MW Electrical power 1600 MW Efficiency 36% No of primary loops 4 No of fuel assemblies 241 Burnup 60 GWd/t Seismic level 0.25 g Service life 60 years Operating Temp 300 o C Pressure 155 Bar Higher steam efficiency comes from higher steam pressures. Through increased heat exchange surface on steam generators.
EPR Simplifications COMPARISON OF EPR EQUIPMENT WITH A TYPICAL 4-LOOP UNIT NORMALISED NUMBER PER MWe 120% 100% 80% 60% 40% 20% 0% Source: Areva 47% fewer valves EXISTING PLANT EPR 16% fewer pumps EXISTING PLANT EPR 50% fewer tanks VALVES PUMPS TANKS HX's EXISTING PLANT COMPONENT TYPES EPR 47% fewer heat exchangers EXISTING PLANT EPR
EPR Containment
EPR Reactivity Control Enriched boron concentrations to control slow reactivity changes Gadolinium neutron absorbers in form of burnable fuel rods for power distribution Rod Cluster Control Assemblies (RCCAs) for rapid reactivity changes Load following through a combination of RCCA movement and boron concentration
Increasing margins to improve fault tolerance and hence safety Larger steam generator volume -> increases secondary side water and steam volume Smoother transients in normal operation reducing unscheduled reactor trips Dry-out time increased to 30 minutes, sufficient time to recover feedwater supply, or initiate other measures Increased RPV volume additional margin to core dewatering in event of LOCA more time available to counteract situation Increased pressuriser volume 25% over N4 smoothes response to operational transients
EPR safety systems
EPR reinforced protection following core meltdown
EPR Core Damage Frequency Predicted Core Damage Frequency for EPR improved by a factor of around 10 compared to N4 and Konvoi Results for Olkiluoto, Finland Transients 45% Loss of coolant accidents 24% Loss of off-site power supply 5% Fires 2% Floods 2% External events 16% Low power and shutdown 6% Total 1.8x10-6 /year
Manufacture of the Olkiluoto RPV (upper part) Casting Forging Machining Machining Non-destructive testing
Westinghouse AP1000
AP1000 - overview 1150 MWe development of the AP600 Minimal change to AP600 2-loop design: 4.27m core larger SGs + pressuriser uprated turbo-generator larger containment building US utilities have selected AP1000 & progressing combined license and construction and operation Westinghouse successful in China contract for 4 new reactors
AP1000 Characteristics Thermal power Electrical power Source: Westinghouse 3415 MW Around 1100 MW Efficiency 32% No of primary loops 2 No of fuel assemblies 157 Burnup 60 GWd/ t Seismic level 0.30 g Service life 60 years Operating Temp 312 o C Pressure 155 bar
AP1000 is Assembled with Proven Components Components Experience Fuel (14 ft. 17x17 ZIRLO) South Texas Reactor Internals Doel 4, Tihange 3 Reactor Vessel Doel 4, Tihange 3 Steam Generators Arkansas, Waterford Pressuriser South Texas Reactor Coolant Pump Other industrial applications Containment Kori 1, 2 & Krsko & Angra Passive safety systems: extensively tested during US licensing
AP1000 Safety / Shut Down Systems Reactor Shutdown Systems (control rods and chemical poisoning) Passive core cooling systems (PXS) Containment Isolation Passive Containment Cooling System (PCS)
Passive Core Cooling System Automatic Depressurisation System to allow low pressure injection of water Injection and coolant makeup from: 1. Core Make-up tanks (CMT) High pressure injection boronated water 2. Accumulators Medium Pressure larger volumes 3. In-containment Refueling Water Storage tank (IRWST) low pressure gravity feed Passive Residual Heat Removal (protection against transients) PRHR Heat Exchanger (sitting in the IRWST) IRWST as heat sink absorbs decay heat for 2 hours
AP1000 Passive core cooling system
AP1000 - Reliability of Ultimate Heat Sink
AP1000 Simplified safety systems achieve safety goals Standard PWR AP1000
AP1000 simplifications 50% Fewer Valves 35% Fewer Pumps 80% Less Pipe* 80% Fewer Heating, Ventilating & Cooling Units 45% Less Seismic Building Volume 70% Less Cable
AP1000 compared with Sizewell B
Very high structural integrity of reactor pressure vessel such that failure is not considered credible. Vessel designed to ensure water delivered to cover the core after a circuit break Assuring vessel integrity Ring forged construction No welds in active core region No longitudinal welds Top mounted in-core instrumentation no bottom penetrations Assuring safety injection to cover the core RPV depressurisation and gravity fed water feed
Core Damage Frequency U. S. NRC Requirements Current Plants Utility Requirements AP1000 Results 1 x 10-4 5 x 10-5 1 x 10-5 4 x 10-7 Core Damage Frequency per Year
ACR-1000 Design
CANDU ACR.
GE Economic Simplified BWR GE s Economic Simplified BWR (ESBWR)
GE s Economic Simplified BWR (ESBWR)
Enhanced natural circulation: No Pressuriser No RCP
ESBWR characteristics Thermal power Electrical power Fuel Assemblies Efficiency Burn-up Operating Temp Pressure Service Life 4,500 MW 1,550 MW 1,132 34.7% 50 GWd/t 287 o C 71 Bar 60 years
ESBWR schematic
Generation III New Nuclear Build in the UK
A Timeline for Replacement Nuclear Build
2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025 2027 2029 2031 2033 2035 MWe 14000 12000 10000 8000 6000 4000 2000 0 Possible Future Nuclear Capacity in the UK Existing stations Potential AGR life extension New Build
UK Current Situation RWE Npower has secured grid connection capacity of 3600 MWe at Wylfa, in Wales, to accommodate three new nuclear power reactors. British Energy, now under EdF, also has grid connection agreements for Wylfa as well as for its two major announced projects at Sizewell and Hinkley Point, German utility EOn has 1600 MWe grid connection agreed for Oldbury. Total grid connection capacity for new UK nuclear plants is now 18.4 GWe
Generation III+ Technology
Pebble-Bed Modular Reactor (PBMR) Small (~400 MWt) modular pebble bed HTR helium cooled, graphite moderated direct cycle gas turbine no secondary steam circuit high outlet temperature: 900 C good thermal efficiency (~ 42%) flexibility for alternative applications high fuel average burnup (~ 80 GWd/tU initially, higher later) very high degree of inherent safety Design based on ABB-THTR Direct cycle technology introduced by PBMR
PBMR fuel design 5mm Graphite layer Coated particles imbedded in Graphite Matrix Dia. 60mm Fuel Sphere Pyrolytic Carbon 40/1000mm Silicon Carbite Barrier Coating Inner Pyrolytic Carbon 40/1000mm Porous Carbon Buffer 95/1000mm 35/1000mm Half Section Dia. 0,92mm Coated Particle Dia.0,5mm Uranium Dioxide Fuel
PBMR Main Power System Recuperators Reactor Unit Compressors Turbine Generator Gearbox Inter cooler Pre cooler
Generation IV Technology
Generation IV Systems Very-High-Temperature Reactor (VHTR) Gas-Cooled Fast Reactor (GFR) Sodium-Cooled Fast Reactor (SFR) Lead-Cooled Fast Reactor (LFR) Supercritical Water-Cooled Reactor (SCWR) Molten Salt Reactor (MSR)
Sodium Cooled Fast Reactor Outlet temp of 550oC Options are Intermediate size (150 to500mwe) supported by fuel cycle based upon non-aqueous reprocessing at-reactor Med to Large size (500 to 1500MWe) supported by fuel cycle based upon aqueous reprocessing at central location Designed mainly for electricity production
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