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Next and Last Generation of Nuclear Power Plants Paul Howarth Exec Director, Dalton Nuclear Institute IMechE Branch Meeting Jan 2009

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Next and Last Generation of Nuclear Power Plants

Paul HowarthExec 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 FissionU235 + n → fission + 2 or 3 n + 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

165 MeV7 MeV6 MeV7 MeV6 MeV9 MeV

200 MeV

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

Standard Fuel Assembly

J A2

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

17%

2%

25%

13%2%

41%

Capital

Decommissioning

Operations andMaintenanceFuel

Spent Fuel Management

Financing

Modern nuclear plant costs are understood and are competitive

Typical costs are in range £30-40/MWhAll costs are accounted for …..

Building to time and cost

89 90 020100999897969594939291 03

Yonggwang 3

Yonggwang 4

Ulchin3

Ulchin 4

Yonggwang 5

Yonggwang 6

Planned schedule

Actual

Net Capacity Factors

50.0

60.0

70.0

80.0

90.0

100.0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

US worldSource: WANO and Nuclear Energy Institute

Expectations for load-factors are high!

Load Factors for new “proto-type” plants

Average Load Factor Over Last Decade of Operation

93

82

8

37

2724

62 63

55

14

0

10

20

30

40

50

60

70

80

90

100

Emsland worldcommercial

reactors

Super-phenix

Phenix DounreayFR

PFRDounreay

WindscaleAGR

WinfrithSGHWR

Julich AVR Fort St VrainHTR

Ave

rage

Loa

d Fa

ctor

(%)

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

• 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

The European Pressurised-water Reactor Design

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

Higher steam efficiency comes from higher steam pressures. Through increased heat exchange surface on steam generators.

Operating Temp 300oC

Pressure 155 Bar

EPR SimplificationsCOMPARISON OF EPR EQUIPMENT WITH A TYPICAL 4-LOOP

UNIT

EXIS

TIN

G P

LAN

T

EXIS

TIN

G P

LAN

T

EXIS

TIN

G P

LAN

T

EXIS

TIN

G P

LAN

T

EPR

EPR

EPR

EPR

0%

20%

40%

60%

80%

100%

120%

VALVES PUMPS TANKS HX's

COMPONENT TYPES

NO

RM

ALI

SED

NU

MB

ER P

ER M

We 47% fewer

valves16% fewer

pumps50% fewer

tanks47% fewer heat

exchangers

Source: Areva

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

• 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

Increasing margins to improve fault tolerance and hence safety

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

Non-destructive testing

Machining

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 Chinacontract for 4 new reactors

AP1000 Characteristics

Thermal power 3415 MWElectrical power Around 1100 MWEfficiency 32%No of primary loops 2No of fuel assemblies 157Burnup 60 GWd/ tSeismic level 0.30 gService life 60 years

Source: Westinghouse

Operating Temp 312oC

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 water2. Accumulators – Medium Pressure larger volumes3. 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’

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

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

Core Damage Frequency

1 x 10-4 5 x 10-5 1 x 10-5 4 x 10-7

Core Damage Frequency per Year

U. S. NRCRequirements

CurrentPlants

UtilityRequirements

AP1000Results

ACRACR--1000 Design1000 Design

CANDU ACR.

GE’s Economic Simplified BWR (ESBWR)GE – Economic Simplified BWR

GE’s Economic Simplified BWR (ESBWR)

Enhanced natural circulation:

No PressuriserNo RCP

ESBWR characteristics

1,132Fuel Assemblies

287oCOperating Temp

71 BarPressure

60 yearsService Life

50 GWd/tBurn-up

34.7%Efficiency

1,550 MWElectrical power

4,500 MWThermal power

ESBWR schematic

Generation IIINew Nuclear Build in the UK

A Timeline for Replacement Nuclear Build

0

2000

4000

6000

8000

10000

12000

1400020

03

2005

2007

2009

2011

2013

2015

2017

2019

2021

2023

2025

2027

2029

2031

2033

2035

MWe

Existing stations Potential AGR life extension New Build

Possible Future Nuclear Capacity in the UK

UK Current Situation

• RWE Npower has secured grid connection capacity of 3600 MWeat 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

Fuel Sphere

Half Section

Coated Particle

Fuel

Dia. 60mm

Dia. 0,92mm

Dia.0,5mm

5mm Graphite layer

Coated particles imbeddedin Graphite Matrix

Pyrolytic Carbon Silicon Carbite Barrier Coating Inner Pyrolytic Carbon Porous Carbon Buffer

40/1000mm

35/1000mm

40/1000mm

95/1000mm

Uranium Dioxide

PBMR Main Power System

Reactor Unit

Recuperators

CompressorsTurbine

Inter cooler Pre cooler

Gearbox

Generator

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

Thank you for listening