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Puget Sound Energy to update hydro design standards

The power generation group of Puget Sound Energy (PSE) is updating and organizing its Hydro Design Standards. These standards cover electrical, mechanical, and civil design. The goal in updating these standards is to support efforts in rehabilitating existing hydro facilities, as well as provide a permanent resource for ongoing operation and maintenance.

PSE will include materials, construction methods, and best practices in the updated standards.

To capture this information, PSE seeks to partner with other utilities. Rather than “reinventing the wheel,” the utility seeks input from others who have already documented this type of information. PSE will share the completed standards with utilities that provide their information, says Chris D. Brown, senior electrical engineer with PSE.

PSE currently is receiving input from utilities and formalizing the table of contents for the standards, Brown says. The utility plans to complete the project by the end of 2009.

– To provide information for the standards, contact Chris Brown, Puget Sound Energy; (1) 425-462-6447; E-mail: chris.d.brown@pse.com.

Utility cost group meets in September

The Electric Utility Cost Group (EUCG), which includes the Hydroelectric Performance Committee, meets Sept. 14-17, 2008, in San Francisco.

EUCG is an association of utility organizations and professionals from throughout the world who share performance and cost information about electric generating facilities, along with best practices for operating and maintaining these facilities. The Hydroelectric Performance Committee (HPC) is an EUCG standing committee. According to committee chair Jim Miller, its members represent a cross section of the hydroelectric industry in North America. The HPC’s database of facilities consists of more than 230 hydroelectric plants ranging in capacity from 350 kW to 6,000 MW. In addition to exchanging plant cost and performance information, members also discuss staffing and safety performance information, Miller says.

At the September workshop, members will review the results from the 2007 data and the best performers in plant peer groups (organized by capacity and use such as run-of-river, tributary, or pumped storage), as well as discuss results of a multi-year analysis, Miller says. In addition, member organizations will present safety and staffing data.

Miller adds that the members will develop plans for a plant management symposium, which will provide a forum for plant personnel to exchange ideas. Potential topics for the future symposium, likely to be held at a member plant, include operations, maintenance, and safety practices and environmental issues.

The EUCG September meeting, with the theme “EUCG Energy Information...Executing Your Strategy,” includes a celebration of the association’s 35th anniversary.

– For information about joining the EUCG and attending the meeting, contact Ms. Pat Kovalesky, EUCG Executive Director, at (1) 623-572-4140; E-mail: eucgexec@cox.net or Jim Miller, chair, HPC, at (1) 423-751-3095; E-mail: ljmiller@tva.gov.

Canadian utilities monitoring greenhouse gas release

Both Manitoba Hydro and Hydro-Québec are using automated systems to monitor fluxes of greenhouse gases – specifically carbon dioxide and methane – in water and air near their hydroelectric projects. Although both utilities are independently running their programs, they work together on improving the methodology and the interpretation of results, says Bob Gill, senior environmental specialist, environmental licensing and protection with Manitoba Hydro.

The initiatives by these two utilities involve installing a continuous monitoring device developed by the Department of Fisheries and Oceans Canada at hydro projects, then collecting data on fluxes of these gases from the reservoirs over time.

Manitoba Hydro installed monitors at its 55-MW McArthur Falls station in 2003, 1,220-MW Kettle in 2004, and 479-MW Grand Rapids and 131-MW Jenpeg in 2006. The utility has calculated annual fluxes of carbon dioxide and methane. The results help Manitoba Hydro better estimate greenhouse gas emissions at the generating stations. These findings also will be used in preparing environmental impact statements for proposed hydroelectric developments.

In 2006, Hydro-Québec installed one monitor each at its 480-MW Eastmain 1, 50-MW Riviere-des-Prairies, and 5,328-MW Robert Bourassa powerhouses, and as well as four monitors in the area around its Eastmain 1 project. This work was part of a larger study on net greenhouse gas emissions from a hydroelectric reservoir. The utility plans to use data gathered from these monitors to evaluate how much its hydro projects contribute to the gross fluctuations in greenhouse gases in the region, Gill says.

These monitors are custom-made and are being used and refined by various entities, including public and private institutions. To facilitate their use, Manitoba Hydro, Fisheries and Oceans Canada, and Hydro-Québec developed an operating manual. This 77-page manual provides a technical description of the monitor, its maintenance requirements, and trouble-shooting issues. The manual also covers flux calculations.

Although there are costs related to the maintenance of these automated systems and interpretation of the data collected, the utilities say it is less expensive than a program where personnel gather this data in the field. Gill says both Manitoba Hydro and Hydro-Québec plan to continue monitoring greenhouse gas emissions in order to better plan hydroelectric developments and to provide information for a national greenhouse gas inventory on a voluntary basis.


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How Reclamation performs seepage investigations

Studies of seepage through dams are complex endeavors that require high-quality data and the knowledge and skills of several disciplines, says Douglas Craft, formerly a research chemist with the U.S. Department of the Interior’s Bureau of Reclamation and now a consultant. Recognizing the complexity of even basic seepage studies and the fact that many engineers and field personnel had little or no background in chemistry, Reclamation developed a standardized five-step approach to seepage chemistry investigations at dams:

  1. ) Developing a sampling plan, which ensures that meaningful information is obtained from the chemical data. Once personnel define the problem, they review pertinent background data, such as piezometer logs, seepage flow logs, and previously collected water chemistry data from the reservoir and seeps.
  2. ) Selecting seepage water sampling sites and chemical tests, with several locations and media considered for collection (ranging from water from the reservoir to solid samples from the foundation). Reclamation also has established guidelines on sample collection timing.
  3. ) Identifying additional samples/ tests that may help interpret the seepage chemistry data, such as geophysical methods, aquifer testing (pump and slug tests on wells), chemical testing of local groundwater from wells away from the reservoir influence zone, stable isotopes analysis of seepage waters, or fluorescent dye tracer testing.
  4. ) Ensuring quality control for chemical analyses and sample collection, including avoiding water samples from surface ponds and catchments that collect seepage from several sources and are subject to surface runoff or evaporation.
  5. ) Analyzing and interpreting data using concentration difference data, chemical equilibrium models, geochemical mass balance models that allow accurate determination of mass wasting and void formation along flow paths from mineral dissolution, groundwater flow models, and models that help evaluate mixing along flow paths.

To aid personnel in performing seepage investigations, Reclamation published the Seepage Chemistry Manual. This 166-page manual, which is available on the Internet for public download, was developed over the course of several investigations into seepage at Reclamation dams. The manual is intended to teach non-chemists how to plan and perform seepage chemistry investigations, how to analyze the samples and interpret the data, and the limitations on the information seepage chemistry data can provide.

Reclamation has applied the seepage study approach to several dams and power plants, including 250-MW Yellowtail and 1,312-MW Glen Canyon.

– To print the manual, visit the Internet: www.usbr.gov/pmts/fish/reports/ craftseepagechemistrymanualfinal DSO-0503web.pdf.


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