New Solutions for NPP Robustness Improvement

New solutions for NPPNew solutions for NPPRobustness Improvement

Dr. Alexander WolskiDirector, Strategic Projects

BULATOM Conference 2013BULATOM Conference 2013Varna, June 5

Fukushima Impact on the IndustryFukushima – Impact on the Industry

► Has triggered a major re-assessment of robustness of nuclear stations

► First round of evaluations has been► First round of evaluations has been finished

► Improvement areas and strategies have ► p o e e t a eas a d st ateg es a ebeen identified

► Implementation of upgrades has started world-wide

► New solutions can provide substantial b fitbenefits

“We must re-think everything we already have thought again, from the beginning”

(Angela Merkel, March 2011)

Improvements DatabaseG i C t i ti d C R f i

REMOO, 2012Ljubljana

Grouping, Categorization and Cross-Referencing

SEISMIC

►> 1500 d t i t GeneralFLOODINGGeneralFlooding protection engineering features/structures, e.g. dykesEXTREME WEATHER CONDITIONSELECTRICAL SYSTEMS

►> 1500 raw data improvements►Condensed to 209 across 72 plants

Almaraz ■■

Asco ■■

Emergency diesel generator (EDG) (Primary)Mobile diesel generator (MDG)…BatteriesHEAT REMOVAL SYSTEMSGeneral

Belene ■■

Borssele ■

Safety injection systems…Spent fuel poolMobile pumpsACCIDENT MANAGEMENTGeneral

…

…

PWR / VVER ■BWR �

GeneralStaffingProcedures (Development & updating)…Hydrogen analysis and mitigationEx-vessel coolingOTHER / GENERAL

Vandellos II ■

Zaporizhzhya ■■■■■■

PHWR ♦UNGG / AGR / Magnox ○

RBMK ‡

OTHER / GENERAL…

RBMK ‡

Improvements Database Interface - Overview


Interface - Overview

Improvements DatabaseA I t Sit


Average Improvements per Site

Improvements Database/Matrix Results


Improvements Database/Matrix Results

COUNT BY CATEGORY

SEISMIC (GENERAL)

HEAT REMOVAL

OTHER

EXTREME WEATHER CONDITIONS

FLOODING

ELECTRICAL POWER

EXTREME WEATHER CONDITIONS

0 500 1000 1500 2000 2500

ACCIDENT MANAGEMENT

Improvements DatabaseTop 10 Improvements


Improvement BWR GCR PWR VVER Others1 Seismic survivability of relevant SSCs 99 99 11 33 11

Top 10 Improvements

1 Seismic survivability of relevant SSCs 99 99 11 33 11

2Seismic Margin Assessment (SMA) / Seismic -PSA 24 44 33 14 11

SSC used for flooding protection (dykes,

3mountable flood walls, building seals, air inlets, doors, flood valves, check valves, mobile pumps, etc.)

13 88 66 11 31

4Diesel and lube oil supplies (volume, versatility,

40 17 22 29 774pp ( , y,

diversity, etc.) 40 17 22 29 77

5 SAMGs 11 53 99 11 26

6Add more EDGs (preferably separated / independent) 60 14 44 43 15independent)

7Filtered containment venting (pressure relief), possibly seismically qualified 44 24 29 22 27

8Access to site and specific areas, transport and l i ti t ft i f t t d 22 33 34 49 168 logistics management after infrastructure damage due to external events (incl. weather)

22 33 34 49 16

9EFW bunkered system protected against floods and earthquakes 111 23 55 78 19

10 Flooding survivability of relevant SSCs 1010 55 23 46 73

Filtered Venting Systemg y

► First filters developed and tested were dry filters► First filters developed and tested were dry filters (implemented in Germany and France)

► Industry today seems to prefer wet filtration solutions► Industry today seems to prefer wet filtration solutions► Current SA calculations show

• Higher temperatures (> 250 ºC)Higher temperatures ( 250 C)• Varying loads of residual heat

► Passive Functionality of wet filters cannot be guaranteed y gunder all conditions

► Modern stainless steel HEPA filters are available from applications in the Nuclear Weapons Industry and Fuel Enrichment Plants

Maximised Filtration Area

HEPA grade filters (99.9% @ 0.3 microns).1,57 m2 footprint44 m2 filtration surface per m3

“German Filter” from the 80’s8,8 m2 footprint1 3 m2 filtration surface per m3 p1,3 m2 filtration surface per m3

Variable Solutions – Example VVER 1000 (320)

► Aerosols remain in Containment

► Replacement of existing aerosol filters – no additional space requiredadditional space required

► No additional penetrations► 100% backup possiblep p► 2nd venting possible

► Solution for VVER 440 (230) developed(230) developed

High Energy Density – Supercritical CO2

> Example: Sandia National Laboratory‘s100 kW shaft power test bench

2

100 kWTurbo-electricgenerator-compressorunit

CompressorsCompressorssufficient forpumping ~2.5 MWthof decay heatof decay heat

Smart Heat Exchanger – self-powered, passive

Power Box

Air Cooler

Power Box

Air Cooler

MG

Optional power for p pair cooling

Pool cooling t

Pool cooling

Spent Fuel Pool 70 – 95 °C

system system

Pb-Batteries – Last Century Technologyy gy

► Mature technology for large energy► Mature technology for large energy storage based on Li-Fe Batteries

► Li-Fe substantially superior to standard consumer products (LiCoO2 / LiMn2O4 orconsumer products (LiCoO2 / LiMn2O4 or LiNiO2)

200 V / 1000 Ah Module

Temperature 0°C / + 45°C -30°C / +60°CHumidity < 85 % at 25°C < 90%Reduced Pressure > 53 kPa > 11.6 kPaCells 100 X Varta Vb 2410 16 x 5 = 80 LiFeWeight 10 760 kg 3 360 kg ( 69%)Weight 10,760 kg 3,360 kg (-69%)Self Discharge 3% / month < 1% / monthDischarge rate (1 hr) 53% 99%g ( )Charging mode CV

30% in fast chargeCV or CC

100% @ 3x nominal currentC l d Lif 20 >> 20 i NPPCalendar Life 20 years >> 20 years in NPPCycle Life >1200 cycles > 6000 cyclesFootprint 7.97 m2 2.24 m2 (-72%)Footprint 7.97 m 2.24 m ( 72%)

WorleyParsons Qualification for Li-Fey Q

► Nuclear requirements from conventional lead batteries have been► Nuclear requirements from conventional lead batteries have been transferred to new technology• IEE 535-20006, Qualification of Class1E Storage Batteries for Nuclear Power

Stations• IEEE 344-2004, Recommended Practice for Seismic Qualification of Class 1E

Equipment• KTA 3703, Emergency Poawer Facilities with Batteries and AC/DC converters, g y• HP-031-01, Russian Design Stanfard for Earthquake resistant NPP

► Existing conventional requirements for have been added• IEC 60896-11, Stationary lead-acid batteries – General requirements and

methods of test• IEC 450-2010, Recommended practice for Maintenance, Testing and

Replacement of vented lead acid batteries for stationary applicationsReplacement of vented lead-acid batteries for stationary applications

► Qualification and Testing Program developed and under execution► Third Party review by credited TSO organizationy y g

Li-Fe Batteries – Advantagesg

► Higher Capacity Discharge (100% @ 30 minutes discharge► Higher Capacity Discharge (100% @ 30 minutes discharge► No hazardous gases (no dedicated ventilation system► Non-explosive, even in direct flames► Real time monitoring► No maintenance, no monitoring / re-filling of water► 1/3 of the floor space 1/3 of the weight► 1/3 of the floor space, 1/3 of the weight► Capacity stable at low temperature and after thousands of cycles► Almost no self-discharge

► Large Battery packs are available with a

capacity of 24 MWhr and a maximum

discharge capacity of 6 MW (20’ container)

Applications in Nuclear Power Plantspp

► Replacement of existing batteries► Replacement of existing batteries• Increase battery capacity by a factor of 3 • Reduce stationary hazards

R d i t i t• Reduce maintenance requirements

► Buffering the start-up of Emergency Diesel Generators• Instantaneous start-up of emergency power systemp g y p y• Relaxation of diesel engine start-up time requirements

► Gas-Turbine-Generators• GTG are highly reliable under severe conditions but have start-up times of 45 to

60 seconds• GTG can be operated with various fuels• GTG are much smaller and contain less parts• GTG have minimum maintenance requirements

► New self-sustained diverse SBO electricity supply► New self sustained diverse SBO electricity supply• 24 MWhr in a simple container

WorleyParsons Nuclear ServicesImprove Example for new solution developmentImprove – Example for new solution development

Steam-driven auxiliary feedwater pump

St d d l ti f W ti h PWRStandard solution for Westinghouse PWRTransfer of concept and experience to other designsRELAP model developed and feasibility demonstrated for VVER 1000Core Cooling without External Power Supply at 6 barN d i t ith t illi tNew pump designs operate without auxilliary systems

On-going developments:Combination with Power-BoxCondensation and re-use of driving steamAdditi l l t i l t dAdditional electrical power generatedAlmost “closed-cycle”; minimum makeup water required

Thank you!Thank you!y