overview of esbwr safety features - atoms for peace and ... · the geh esbwr builds on the...

Copyright 2013 GE Hitachi Nuclear Energy International, LLC - All rights reserved

Overview of ESBWR

Safety Features

Gary Miller Senior Application Engineer

INPRO Dialogue Forum

November 19-23, 2013


Introduction

The GEH ESBWR builds on the successful operational history of the GE BWR product line including the only Generation III reactor in operation, the ABWR.

The GEH ESBWR is designed to incorporate:

• state-of-the-art technology,

• simplification,

• passive safety features,

• less dependence on operator actions, and

• no dependence on safety-related diesel generators.

2


ESBWR Basic Parameters

4,500 Megawatt core thermal power

~1,575 to 1,600 MWe gross

• Nominal summer rating

Natural circulation

• No recirculation pumps

Passive safety systems

• 72 hours passive capability

Operating cycle length of 12 to 24 months

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11 fewer major systems 25% fewer components

ESBWR Overall Flowchart

4


ESBWR 60-Year Design Life

No need to replace or make major refurbishments to nuclear steam supply system (NSSS), containment, or safety related structures

Where cost effective, safety-related components qualified for 60-year lifetime

Some overhaul / replacement work can be performed online (e.g., battery banks)

Design of I&C based on non-proprietary standards with large margins included in design

• Allows for inevitable obsolescence and subsequent increases in performance

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Parameter BWR/4-Mk I

(Browns Ferry 3)

BWR/6-Mk III

(Grand Gulf 1)

ABWR ESBWR

Power (MWt / MWe) 3293/1098 3900/1360 3926/1350 4500/1590

Vessel height / diameter (m) 21.9/6.4 21.8/6.4 21.1/7.1 27.6/7.1

Fuel Bundles (number) 764 800 872 1132

Active Fuel height (m) 3.7 3.7 3.7 3.0

Power density (kW/l) 50 54.2 51 54

Recirculation pumps 2 (large) 2 (large) 10 zero

Number of CRDs / type 185/Locked

Piston

193/Locked

Piston

205/Fine Motion 269/Fine

Motion

Safety system pumps 9 9 18 zero

Safety Diesel Generator 2 3 3 zero

Core damage freq./yr 1E-5 1E-6 1E-7 1E-8

Optimized Parameters for ESBWR

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Copyright 2013 GE Hitachi Nuclear Energy International, LLC - All rights reserved 7

Dresden 1 KRB

Oyster Creek Dresden 2

ABWR ESBWR

BWR evolution


• Introduced in 1972

• Characteristics:

o Added fuel bundles; increased

output

o 8 x 8 fuel bundle

o Improved Recirculation

system performance

o Compact jet pumps

o Valve flow control

o 20% more power for same

size reactor

o Mark III containment

o Core damage frequency ~10-6

• Plants (8):

o Clinton 1 (USA)

o Cofrentes (Spain)

o Grand Gulf 1 (USA)

o KKL (Switzerland)

o Kuo Sheng 1&2 (Taiwan)

o Perry 1 (USA)

o River Bend 1 (USA)

BWR 6: Characteristics and Plants

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BWR evolution


Mark III Containment

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ESBWR plant / reactor characteristics

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Key Safety

Functions

Reference Plant: BWR 6 ESBWR

Coolant

Injection

High Pressure Core Spray:

1 Train - Motor Driven Pump with

dedicated Diesel Generator

Reactor Core Isolation Cooling:

1 Train -Turbine Driven Pump

Control Rod Drive Bypass Flow

Automatic Depressurization System:

Safety/Relief Valves

Low Pressure Core Spray:

1 Train - Motor Driven Pump

Low Pressure Coolant Injection:

3 Trains - Motor Driven Pumps

2 Diesel Driven Fire Water Pumps

Gravity-Driven Cooling System:

4 Trains No Pumps

Automatic Depressurization System:

Safety/Relief Valves and Squib-

actuated Depressurization Valves

High Pressure Control Rod Drive

System Flow:

1 Train Motor Driven Pump

Low Pressure Injection:

2 Trains Motor Driven Pumps

Isolation Condensers:

4 Trains Natural Circulation, Passive

actuation

1 Diesel Driven Fire Water Pump


4500


11

Key Safety

Functions


Containment

Cooling

2 Trains - Motor Driven Pumps

with Heat Exchangers

Wetwell venting

Passive Containment Cooling

Heat Exchangers:

6 Trains Natural Circulation

Wetwell venting


4500


12

Key Safety

Functions


Reactivity

Control

Hydraulic Control Rod Drive

System

Standby Boron Injection System

with Charging Pumps

Hydraulic Control Rod Drive

System with Mechanical Drive

Back-up

Passive Standby Boron Injection

System

Key

Supporting

Systems

AC Power – 2 Emergency Diesel

Generators + 1 HPCS Emergency

Diesel Generator

DC Power – 12 hour Batteries

Service Water for component

cooling and decay heat removal

Cooling Pools for Isolation

Condenser and Passive

Containment Cooling

DC Power – 72 hour Batteries

Diesel Generator and Service

Water available for alternative

cooling paths, but not required



13

General

Response to:


Loss of

Coolant

Accident

High Pressure Core Spray,

Reactor Core Isolation Cooling,

Low Pressure Core Spray, Low

Pressure Coolant Injection,

Firewater

Core becomes partially

uncovered during design basis

LOCA

Gravity-Driven Cooling System,

High Pressure Control Rod Drive

Injection, Low Pressure Injection,

Firewater

Core remains covered during

design basis LOCA



14

General

Response to:


Loss of Heat

Sink

Reactor Shutdown

Containment Isolation

Safety/Relief Valves discharge to

Containment Suppression Pool

Cope for 12 hours using non-AC

injection until heat sink is

restored

Reactor Shutdown

Containment Isolation

Isolation Condensers actuate,

removing decay heat to

atmosphere

Restore water to Cooling Pools

after 72 hours


ESBWR LOCA response

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overview of esbwr safety features - atoms for peace and ... · the geh esbwr builds on the...

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