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Physics and the AP1000

“Passive Safety”

Simon Marshall

GDA Project Director

Westinghouse UK

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Physics and the AP1000Agenda

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Physics and the AP1000 Options to Achieve Low Core Damage Frequency?

● Evolutionary plants achieve goals

by adding redundant safety

features

– 4 Train Safety Injection

– 4 Train Decay Heat Removal

– 4 Train Containment Cooling

– 4 Train Residual Heat Removal

– 4 Train Diesel Generators

● Leads to increased:

– Increased complexity

– Increased capital

– Increased O&M cost

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Physics and the AP1000 Options to Achieve Low Core Damage Frequency?

● Passive Plants achieve goals by using

naturally occurring physical phenomena

such as:

– natural circulation of air, water and

steam

– gravity and gas pressure drive the flow

of cooling water

– natural heat transfer occurs through

conduction, convection and evaporation

● A few battery powered valves align the

passive safety systems upon actuation

signals

● Reactor safety functions are achieved

without AC power

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Physics and the AP1000 Passive Core Cooling System at Work

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Physics and the AP1000 Passive Containment Cooling

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1 x 10-4 5 x 10-5 <1 x 10-5 5.1 x 10-7

(All Events)

U. S. NRC

Requirements

Current

Plants

Utility

Requirements

Physics and the AP1000 Impact of Passive Systems - Core Damage Frequency

AP1000

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Physics and the AP1000Impact of Passive Systems - Equipment

50% Fewer

Safety-grade

Valves

35% Fewer

Pumps

80% Less

Safety-grade

Pipe

45% Less

Seismic Building

Volume

70% Less

Cable

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Power Concrete, m3 Rebar, MT

Sizewell B 1188 MWe 520,000 65,000

AP1000 1117 MWe < 100,000 < 12,000

Physics and the AP1000 Impact of Passive Systems - Layout

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2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

Physics and the AP1000 Building on Success

Sanmen 1

Haiyang 1

Sanmen 2

Haiyang 2

Vogtle 3

VC Summer 2

Vogtle 4

VC Summer 3

Levy 1

Levy 2

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Pump/Valve Module

Raceway ModuleStructural Module

Depressurization Module

Module Type

Structural

Piping

Mechanical

Equipment

Electrical

Equipment

TOTAL

Number

122

154

55

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342

Physics and the AP1000 AP1000 Modular Design

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Physics and the AP1000 AP1000 Modular Design

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Physics and the AP1000 AP1000 Modular Design

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Thank You