Leading Utilities Attend Full Week of CEATI Hydro Events

The CEATI Hydropower Program hosted a weeklong series of events, including an industry Symposium on Penstocks and general meetings for its Dam Safety and Hydraulic Plant Life Interest Groups from March 12-16, 2012 in Santa Monica, CA.

The Penstock Symposium was a rousing success, with attendees from nearly 60 utilities located around the world. The event featured three sessions, on 1) Technical/Engineering Approaches to Maintaining Penstock Reliability, 2) Asset Investment Planning and 3) Case Studies. The knowledge sharing benefits were a real “eye-opener” according to one attendee, with many agreeing that the workshop’s program delivered immense value by providing comparisons of different organizations’ experiences with Penstocks.

Pat Regan of the Federal Energy Regulatory Commission (FERC) spoke of their Penstock database, which looks at hazards, consequences, and determined risk levels during his presentation  “Risk-Informed Approach to Penstock Safety”. The database revealed key issues on a number of fronts, including geotechnical and equipment malfunction, as well as aging, fabrication and operator error.

Attendees also listened to a talk by Philippe Bryla and Pierre Saint-Joanis about the “Penstock Diagnoses and Rehabilitation Program” at Électricité de France (EDF). By assessing their Penstocks’ structural losses of resistance and external loads, EDF ranks Penstocks according to their level of risk, allowing them to make sound decisions. Thomas Kahl of Klenschmidt Associates covered different types of failures modes and inspection techniques in his presentation “Failure Mode Condition Assessment”.

Charlie Ahlgren and Justin Tomljanovic of Pacific Gas and Electric (PG&E) presented the evolution of PG&E’s Penstock Program during the workshop’s second session. PG&E utilized a risk-based approach to complete an assessment of their entire hydro system. Their experiences taught them to develop a scope limited to what is required to reflect the root causes of historical incidents and to define the problem and make a recommendation.

A comparison between SMUD’s experiences with visual and automatic inspection and monitoring revealed the advantages and drawbacks of each during Chris Moffit’s presentation. Additional case study examples were given HATCH and Ontario Power Generation (OPG) which highlighted practical takeaways on some of the common factors leading to Penstock replacement, and on cost-effective Penstock assessments.

Owners Discuss Model Dam Safety Program

The Penstock Symposium was preceded by the Dam Safety Interest Group (DSIG) spring General Meeting, held on March 12-13, 2012. According to one participant, these general meetings are an “excellent way to “pool” resources, share experiences (both good and bad) and develop a network of contacts“.

The meeting featured a nearly full day Technical Workshop on “Model Dam Safety Program and Performance Measures”. Within the collaborative context of the participant-only meeting, representatives from major hydropower utilities, including Ameren, OPG, E.ON, PG&E, TransAlta, Manitoba Hydro, Hydro-Quebec, and Southern Company, shared illustrative examples of their own efforts towards developing effective and complete safety programs. FERC also presented on the relevance of developing a Dam Safety Program in today’s regulatory climate.

The group received updates on ongoing research, such as the “Grouted Anchor Assessment Program” and the “Dam Safety Performance Monitoring and Data Analysis Management – Best Practices”. Both projects address important questions regarding dam safety. By researching and evaluating the condition of grouted anchors, through literature review and forensic study, the resulting anchor program will help sponsors make risk-based decisions regarding anchor replacement. The second endeavor will document best practices to develop an instrumentation program, identify responsibilities of management, and ensure proper coordination among program components.

Other potential and ongoing efforts include:

• Benchmarking Flood Hazard Estimation Methods
• Multifractal and Physically Based Estimates of Extreme Floods
• Integration of Inundation Mapping into Community Emergency Plans Using Geographic Information Systems (GIS) Technology
• Activation and Notification Guidelines for Emergency Preparedness Plans
• Structural Safety for Fractured Concrete Dams
• Dam Safety Training for Plant Operators
• NAS – State of the Art and Practice in Earthquake Induced Soil Liquefaction Assessment

55 Utilities Gather to Exchange Knowledge on Hydraulic Plant Asset Management Practices

The Hydraulic Plant Life Interest Group (HPLIG) meeting, held March 15-16, 2012, featured a technical session on the RusHydro Accident, with presenters giving examples of the changes their utilities implemented following the tragedy. Fortum reviewed its “Major Accident Risk Evaluation (M.A.R.E.)” program, which is studying high risk stations for issues based on high head, vibrations, and loose or cracked rocks, for example. Their program will continue until all of their high risk stations have been evaluated. The U.S. Army Corps of Engineers conveyed the status of its safety inspection procedures, done every 6 years or less, which aim to inspect safety with a minimum of intrusion. These inspections cover typically designed machines, and components include head cover studs/nuts, wicket gate timing, and access doors.

This summer, the Penstock Task Forceand the Asset Management Task Forcewill meet on June 12-15, 2012 in Seattle, WA. The Penstock Task Force will review outcomes of the Symposium whereas the Asset Management Task Force will study approaches, processes and tools used to support key asset management steps and decisions.

A half day workshop put on by Hatch looked at “Engineered Equipment: Supplier Qualification/Quality Assurance/Quality Control. Their in-depth, practical talk on “Emerging Country Sourcing Risk Management” offered insight on how to develop a successful global sourcing strategy. In the case of emerging countries, they shared best practices to implement both pre and post contract award. Rescue missions, case studies and supplier profiles helped convey the importance of specific guidelines which should be put into practice.

HPLIG also reviewed ongoing projects, including its technology review efforts, like a Brushgear Maintenance Guide. A draft of the final report is currently under review.

Other ongoing projects and technology reviews include:

• Alignment Guide Update
• Criteria for the Identification and Selection of Environmentally Acceptable (EA) Lubricants
• Dissection, Condition Assessment and Analysis of Failed and Un-Failed Aged Stator Windings Taken From Hydro Generators
• Turbine/Generator Shaft Stress Analysis – Methods and Limitations
• Stator Core/Rotor Pole Replacement/Refurbishment Criteria
• Operation of Hydro Generators with Bypassed Stator Coils
• Hydro Generators – General Maintenance and Inspection Guide
• Hydro Turbine Generator Electrical Overhaul Guide
• Operation of Hydro Generators with Bypassed Stator Coils
• Transformers: An In-Service Guide for New and Used Transformers (Factory Tests, Transportation, Storage, In-Service Tests)

HPLIG concluded their meeting by honoring the outgoing Chair Andrew Datsko of FirstEnergy. Mr. Datsko has been an active participant in the group since 2005, and will continue to contribute to HPLIG’s research efforts in the years to come.

Upcoming CEATI Hydropower Events Create Further Occasions for Information Exchange

Sponsored by a group of 15 dam owners, a workshop entitled “Seismic Hazard and Risk Assessment”, scheduled for May 24-25, 2012 in San Francisco, CA, will describe state-of-practices within the hydropower industry with regards to seismic hazard assessment, seismic evaluation of dams, and seismic remediation practices. Panel discussions will provide a chance for DSIG members to raise questions and share insights, as well as determine possible future projects on the topic.

Upcoming Open Industry Events – Save the Date!

• Planning for Extreme Events: A Dam Safety and Water Management PerspectiveOctober 15-16, 2012 in Montreal, QC – Registration Now Open

• Case Studies WorkshopMarch 12-13, 2013
  Las Vegas, NV