Page 1 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Why Is Reliability, Availability, Maintainability, and Inspectability Important to the Future of Fusion? Why Is Reliability, Availability, Maintainability, and Inspectability Important to the Future of Fusion? L. Waganer Consultant for The Boeing Company Harnessing Fusion Power Workshop 2-4 March 2009 University of California-Los Angeles

Page 2 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Greenwald Theme - Harnessing Fusion Power The state of knowledge must be sufficient to design and build, with high confidence, robust and reliable systems which can convert fusion products to useful forms of energy in a reactor environment, including a self-sufficient supply of tritium fuel. Specifically for Reliability, Availability and Maintainability Demonstrate the productive capacity of fusion power and validate economic assumptions about plant operations by rivaling other electrical energy production technologies.

Page 3 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA The End Goal For Fusion - Produce Competitive Electrical Power Our immediate goals are how to: 1) assess our current technology maturity, 2) determine our gaps, and 3) postulate research thrusts to close the gaps This will enable Demo to validate that the ultimate goal can be achieved with acceptable risk

Page 4 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA How Can RAMI Help? The busbar cost of electricity is the most important factor for an electrical generating power plant. The plant must be an affordable, reliable, maintainable energy source and all of these factors are contained in the cost of electricity: COE = [C AC + (C O&M + C SCR + C F ) * (1 + y) Y + C D&D, where (8760*P E * P f ) C AC is the annual capital cost charge (total capital cost x Fixed Charge Rate) C O&M is the annual operations and maintenance cost C SCR is the annual scheduled component replacement cost C F is the annual fuel costs y is the annual escalation rate (0.0 for constant dollar and y for current dollar) Y is the construction and startup period in years P E is the net electrical power (MWe) P f is the plant capacity factor (~ plant availability ) C D&D is the annual decontamination and decommissioning converted to mills/kWhr Major Effect Minor Effect (salaries, equip) Minor Effect (cost, life)

Page 5 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Plant Availability is High Leverage Tool - Equivalent in Importance to Power Production - Operational Time is the power production time over a set period of time. Scheduled Down Time is the sum of regularly scheduled maintenance periods for the power core, other reactor plant equipment, and balance of plant equipment - Related to component lifetimes, replacement schedules, and MTTR The Unscheduled Down Time is the summation of maintenance times to repair unexpected operational failures that cause the plant to cease power production – Determined by MTTR/MTBF of all critical components Availability = Operational Time Operational Time + Scheduled Down Time + Unscheduled Down Time

Page 6 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Availability is Determined by: 1.Reliability – The inherent reliability of all the power core and plant component parts to achieve a very high system reliability, (> 0.99). This means that individual components are validated to achieve extremely high levels of reliability. 2.Maintainability – The ability to rapidly and reliably maintain all the plant parts, especially the remote maintenance of the power core, is absolutely essential. Power core maintenance may be highly automated and likely autonomous in 50 years. 3.Inspectability - An examination of plant components to determine if there are any indications that components might fail in service, any reduction or increase in performance and/or service lifetime. This implies extensive pre- and post- operational examinations, along with an embedded, real-time monitoring of all operational components as a part of an integrated plant health management system that will predict and schedule preventative maintenance actions (new technology).

Page 7 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Vision of Power Core Maintenance ITER and other DT experimental facilities have, or will have, provided a wealth of remote handling experience that will be applicable to CTF, Demo, and the Commercial Power Plant However, those machines were never designed to have rapid remote maintenance to achieve very high levels of availability Conceptual fusion power plant studies have postulated two general approaches that have some promise (and a lot of difficulties) to achieve the required availability goal. A. Remove large blanket and divertor modules with articulated arms and installed rails through several large maintenance ports B. Remove complete sectors containing blankets, divertors, and hot shield/structure between TF coils and radially out through large vacuum maintenance ports.

Page 8 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA A. Modular Maintenance Approach Simultaneous maintenance in 3 ports Module size limited to several tonnes Fixed Transfer Chambers control contamination and enhance times Mobile Transporters transfer used and new components to/from Hot Cell Main Port is used for removing blanket and divertor modules ECH launcher/waveguide removed ECH port can then be used as Auxiliary maintenance port

Page 9 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Removal of Blanket Modules Plumbing would be disconnected from inside the plumbing pipes A mobile Extractor machine would enter the maintenance port and disconnect the mechanical attachments Modules would be extracted from core and returned to Hot Cell The above actions repeated for all modules New or refurbished modules would be reinstalled and tested in- situ (repeated actions)

Page 10 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Requires a higher degree of integration between power core elements, power core building, and maintenance approach Simplifies coolant and mechanical connections outside of hot shield Allows simpler power core maintenance, but more massive elements to be moved with precision B. Sector Maintenance Approach More fluid and structural connections pre- tested in hot cell rather than inside power core

Page 11 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Example of AT Sector Replacement Basic Operational Configuration Withdrawal of Power Core Sector with Limited Life Components Cross Section Showing Maintenance Approach Plan View Showing the Removable Section Being Withdrawn

Page 12 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Sector Removal Remote equipment is designed to remove shields and port doors, enter port enclosure, disconnect all coolant and mechanical connections, connect auxiliary cooling to the sector, and remove power core sector

Page 13 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Operational Configuration Bioshield (2.6-m-thick) is incorporated into building inner wall Building wall radius determined by transporter length + clear area access Extra space provided at airlock to assure that docked cask does not limit movement of other casks

Page 14 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Power Core Removal Sequence Cask contains debris and dust Vacuum vessel door removed and transported to hot cell Core sector replaced with refurbished sector from hot cell Vacuum vessel door reinstalled Multiple casks and transporters can be used Multiple locations can be accessed simultaneously

Page 15 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Power Core Removal Sequence Cask contains debris and dust Vacuum vessel door removed and transported to hot cell Core sector replaced with refurbished sector from hot cell Vacuum vessel door reinstalled Multiple casks and transporters can be used Multiple locations can be accessed simultaneously

Page 16 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Shutdown and Start-up Times Must Be Minimized Shutdown Timeline Startup Timeline Dominated by cooldown of systems and core Assumes streamlined processes for core evacuation, bakeout, and coolant fills = 2.6 days

Page 17 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Estimated Repetitive Maintenance Times for Replacement of a Single Power Core Sector Assumes a single cask and transporter Defines major maintenance activities Assumes all removal and replacement activities are remote and automated Repetitive actions require less than 1.5 days

Page 18 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Maintenance Times for Replacing Different Number of Sectors at a Time Note: Blankets, Divertors, and other In-Vessel Components are designed for a 4 full power year (FPY) lifetime One Cask and One Transporter

Page 19 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Multiple Sets of Casks and Transporters Can Improve Times At least two sets should be used (4.23 equivalent d/y) Availability improvements by larger numbers of casks and transporters probably would not justify added cost Spare maintenance equipment will be provided Equivalent Annual Maintenance Times for Multiple Sets

Page 20 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Need to Establish Fusion Power Plant Availability Goals Consistent with Energy Community All reasonably new electricity-generating plants are now operating in the 85-90% class In years, state-of-the-art plant availabilities will be 90+% Fusion Power Plant (FPP) needs get to 90% or better Representative Plant Systems Availability Goals

Page 21 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA What Should Be Demo’s Availability Goal? This notional graph illustrates how Availabilities have to grow through ITER, CTF, and DEMO Now

Page 22 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Summary Achieving RAMI goals are imperative to the success of fusion producing competitive power Designs shown are merely ideas at this point to help point the way to an integrated power plant design Power core elements must be highly reliable and robust through simulation and test Efficient maintenance of the power core is highly design dependent High availabilities must be demonstrated by CTF and Demo Demo must look like and act like the first commercial power plant

Page 23 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Recommendations An integrated power core, maintenance system, and building design is essential to help select subsystem options for Demo and the Fusion Power Plant (FPP) Pre-cursor facilities and thrusts must mature and validate subsystems and maintenance systems that are a part of an integrated design approach leading to Demo and ultimately to the FPP An Integrated Plant Health Management system is necessary to predict and schedule preventative maintenance actions

Page 24 HFP Workshop, RAMI Session, 2-4 Mar 2009k,UCLA Questions?