.1 Babcock & Wilcox Proprietary Information Introduction to mPower IRUG Conference Salt Lake City, Utah July 27, 2011 Jason Williams Babcock&Wilcox

.2 Babcock & Wilcox Proprietary Information Outline Introduction Plant layout Integral reactor design Safety concept Development testing Methods Development Conclusion

.3 Babcock & Wilcox Proprietary Information  Alliance between B&W and Bechtel Risk sharing with 90/10 current ownership 250+ FTE development team  Technology and project execution Turnkey projects = cost/schedule certainty  Broad industry engagement Investment from 15 member Consortium 26 member Industry Advisory Council  Goal is to deploy lead plant by 2020 Industry side of public-private partnership Platform for industry cost/risk sharing Nebraska Electric G&T Cooperative Hoosier Energy Rural Electric Cooperative, Inc. Generation mPower Industry Consortium Industry Partners Industry Advisory Council Includes Consortium members above plus: AEP Dayton Power & Light Duke Energy Exelon NPPD Vattenfall Bruce Power Dominion Entergy MidAmerican Progress Energy

.4 Babcock & Wilcox Proprietary Information Goal and Value Proposition Develop and deploy, by 2020, an SMR that offers: Lower Capital Cost Schedule & Cost Certainty Competitive LCOE Pricing Within the constraints of:  Proven: GEN III +, established NRC regulation  Safe: Robust margins, passive safety  Practical: Standard fuel, construction and O&M  Benign: Underground, small footprint.4

.5 Babcock & Wilcox Proprietary Information.5 High-Level Requirements 125 MWe Nominal Output per Module and 60-Year Plant Life NSSS Forging Diameter Allows Readily Available Forgings and Unrestricted Rail Shipment Passive Safety Requirements – Emergency (Diesel) Power Not Required  Minimize Primary Coolant Penetrations, Maximize Elevation of Penetrations  Large Reactor Coolant Inventory  Low Core Power Density Standard Fuel (less than 5% U 235 ) Long Fuel Cycle, 4+ Year Core Life Spent Fuel Storage on Site for Life of Plant No Soluble Boron in Primary System for Normal Reactivity Control Conventional/Off-the-Shelf Balance of Plant Systems and Components Accommodate Air-Cooled Condensers as well as Water-Cooled Condensers Flexible Grid Interface (50 Hz or 60 Hz) Digital Instrumentation and Controls Compliant with NRC Regulations © 2011 The Babcock & Wilcox Company. All rights reserved. 5

.6 Babcock & Wilcox Proprietary Information.6  “ Twin-pack” mPower plant configuration  40 acre site footprint  Low profile architecture  Water or air cooled condenser  Enhanced security posture  Underground containment  Underground spent fuel pool  Lower overnight construction cost  Competitive levelized cost of electricity © 2010 Babcock & Wilcox Nuclear Energy, Inc. All rights reserved. Patent Pending The B&W mPower Nuclear Plant Security-informed plant design contains O&M costs

.7 Babcock & Wilcox Proprietary Information Integral Reactor © 2011 The Babcock & Wilcox Company. All rights reserved. Simplified – Integrated, Pressurized Water Reactor Internal Components to Minimize Penetrations  Control Rod Drives – No rod ejection  Coolant Pumps – Not safety related Control Rods versus Boron Shim Load Following Capability – Up to 10%/Min Passive Safety  No safety-related emergency diesel generators  No core uncovery during design basis accident (small break LOCA) Performance of Critical Functions by Multiple Systems for Improved Reliability and Plant Safety Multiple Module Plants – BOP Equipment Not Shared

.8 Babcock & Wilcox Proprietary Information Pressurizer Steam Generator Tubes Reactor Coolant Pumps (12) Control Rod Drive Mechanisms (61) Core (69 Bundles) Steam Outlet (2) Feedwater Inlet (2) Integral Reactor Arrangement 1900 psia, 609°F Core Outlet 568°F Core Inlet 25.4M lbm/hr Primary Loop 571°F at 825 psia 50°F Superheated Steam 325°F Feedwater Secondary Loop Central Riser

.9 Babcock & Wilcox Proprietary Information  Ensure that assemblies are mechanically designed to remain leak tight and maintain structural integrity under all possible conditions  Load enough fuel inventory to accommodate a 4 year operating cycle at a capacity factor of > 95%  Optimize fuel assembly design to maximize fuel utilization  Maintain conservative peaking factors and linear heat rate throughout the operating cycle  Ensure a shutdown margin of > 1%  k eff /k eff under the most reactive conditions and highest worth CRA cluster stuck out  Meet a MDNBR > 1.3 for limiting thermal-hydraulic conditions and confirm via unique CHF correlation Design Objectives – Core and Fuel Assembly

.10 Babcock & Wilcox Proprietary Information  69 fuel assemblies  < 5 wt% 235 U enrichments  Two fuel assembly configurations  No soluble boron for control  Axially graded BPRs  Gd 2 O 3 spiked rods  Control rod sequence exchanges  AIC and B 4 C control rods  3% shutdown margin Core Design Features

.11 Babcock & Wilcox Proprietary Information Fuel Mechanical Design Features 11 Shortened and Simplified Conventional Fuel Assembly Design Conventional 17x17 design Fixed grid structural cage Design optimized for mPower © 2010 Babcock & Wilcox Nuclear Power Generation Group, Inc. All rights reserved. Upper End Fitting End Grid (Inconel-718) Mid Grid (Zircaloy-4) 17 x 17 Square Array Control Rod Guide Tube (Zircaloy-4) End Grid (Inconel-718) Lower End Fitting © 2011 The Babcock & Wilcox Company. All rights reserved.

.12 Babcock & Wilcox Proprietary Information.12 Low Core Linear Heat Rate  Low Power Density Reduces Fuel and Clad Temperatures During Accidents  Low Power Density Allows Lower Flow Velocities that Minimize Flow Induced Vibration Effects Large Reactor Coolant System Volume  Large RCS Volume Allows More Time for Safety System Response in the Event of an Accident  More Coolant Is Available During a Small Break LOCA Providing Continuous Cooling to Protect the Core Small Penetrations at High Elevation  High Penetration Locations Increase the Amount of Coolant Left in the Vessel after a Small Break LOCA  Small Penetrations Reduce Rate of Energy Release to Containment Resulting in Lower Containment Pressures Inherent Safety Features CONFIDENTIAL AND PROPRIETARY TO B&W

.13 Babcock & Wilcox Proprietary Information Key Features of the Integral RCS * Assumes double ended break RCS volume and small break sizes allow simplification of RCS safety systems © 2011 The Babcock & Wilcox Company. All rights reserved.

.14 Babcock & Wilcox Proprietary Information ECCS Safety Functions Removes core heat following certain anticipated operational occurrences and analyzed accidents Reduces containment pressure and temperature following certain analyzed accidents Provides an alternate means of reactivity control for beyond design basis accidents (i.e. ATWS) Provides a barrier to the release of fission products to the environment

.15 Babcock & Wilcox Proprietary Information B&W mPower Containment Underground containment and fuel storage buildings Metal containment vessel Environment suitable for human occupancy during normal operation Simultaneous refueling and NSSS equipment inspections Leakage free Volume sufficient to limit internal pressure for all design basis accidents © 2010 Babcock & Wilcox Nuclear Energy, Inc., All rights reserved.

.16 Babcock & Wilcox Proprietary Information.16 Component Tests  Reactor Coolant Pump  CRDM  Fuel Mechanical Testing  CRDM/Fuel Integrated Test  Fuel Critical Heat Flux  Emergency High Pressure Condenser Integrated Systems Test (IST)  Heat Transfer Phenomena  Steam Generator Performance  LOCA Response  Pressurizer Performance  Reactor Control Development Testing Programs Center for Advanced Engineering Research (CAER) Bedford, VA

.17 Babcock & Wilcox Proprietary Information Principal Computer Codes Current thinking… RELAP5-3D  Primary T/H system transient response  Multi-dimensional hydrodynamics, reactor kinetics  Large code assessment database for PWR T/H phenomena  RELAP5-HD (simulator tool from GSE) available for supplemental T/H analysis GOTHIC  Containment analysis  Supplemental T/H system transient response

.18 Babcock & Wilcox Proprietary Information Evaluation Methodology Development and Assessment Process (EMDAP) (RG 1.203)

.19 Babcock & Wilcox Proprietary Information Identify and Rank Phenomena Preliminary PIRTs  SB LOCA – Ortiz, Ghan, NUREG/CR-5818  Non LOCA – Greene, et al., ICONE 9, 2001  Containment – OECD/NEA CSNI Final PIRTs  SBLOCA – DEGB in mid-flange attached pipe Plans  Long-term Non LOCA events (±  T, ±Vol, -Flow)  Short-term Non LOCA events (reactivity anomalies)

.20 Babcock & Wilcox Proprietary Information Specify Figures of Merit Chapter 15 Non LOCAs  DNBR  Fuel centerline temperature  Primary and Secondary Pressure  Mass and Energy releases for Chapter 6 analysis (Steamline break only) Chapter 15 LOCA  Liquid level, surrogate for peak clad temperature and oxidation-related measures  Mass and Energy releases for Chapter 6 analysis Chapter 15 Reactivity initiated events  Fuel enthalpy (also feeds into source term assumptions in radiological) Chapter 15 Radiological events  A person located at any point on the boundary of the exclusion area for any 2- hour period would not receive a dose in excess of 25 rem  A person located at any point on the outer boundary of the low population zone would not receive a dose in excess of 25 rem Chapter 6 Containment events  Pressure

.21 Babcock & Wilcox Proprietary Information Conclusion B&W and Bechtel have formed an alliance to design and construct the mPower SMR plant The mPower modular reactor plant has a unique integral reactor design with passive safety system design Design and licensing activities are well underway A comprehensive test program is in process A letter of intent has been signed with TVA for up to six units for deployment of the first unit by 2012