Close 

Tech Briefs

GRDA uses infrared camera to locate pollution in reservoirs

Grand River Dam Authority (GRDA) is using a camera equipped with infrared functions to identify sources of pollution in Grand and Hudson lakes. These lakes are impounded by the 120-MW Pensacola and 114-MW Robert S. Kerr hydroelectric projects in Oklahoma.

The camera uses infrared imaging to detect thermal energy. Mounted under the nose of a helicopter, the camera allows GRDA to obtain infrared images of the lakes. Hot spots along the shoreline could indicate septic system leaks. GRDA also will use the camera to identify boats that have illegally dumped sewage from their holding tanks.

GRDA bought the refurbished camera – manufactured by FLIR Systems – from the California Highway Patrol for $50,000. GRDA owns a helicopter and has trained several employees to use the equipment.


An infrared camera mounted under the nose of a helicopter allows Grand River Dam Authority to identify sources of pollution in the reservoirs impounded by its hydroelectric projects.
Click here to enlarge image

Other uses for the camera include checking transmission lines and substations to identify hot spots on transformers, breakers, and insulators that require maintenance. In addition, the camera’s standard imaging technology is useful for gathering aerial footage.

Software available to aid in site assessment

Nine hydro consultants in Canada, Colombia, New Zealand, and the U.S. are testing beta versions of a new software series called HydroHelp. These programs were developed to allow engineers to obtain an initial assessment of a hydroelectric site with a minimum of data. The programs use Microsoft Office’s Excel 2003 on a Windows XP operating system.

Several versions are being produced:

– HydroHelp Beta SH (small hydro) series is designed for individuals and small consultants. The program will perform calculations for projects up to 50 MW (based on calculation of flow times head), with no more than two embankment dams.

– HydroHelp Beta LH (large hydro) series is designed to cover all sizes of projects, with no upper limit but a limit of two embankment dams.

– HydroHelp professional series is designed for large consultants and covers all sizes of hydro projects. The programs are not protected with locks to limit the scope of the project, there is no limit to the number of embankment dams, and all algorithms are visible.

Each series features four programs, all for surface power plants:

– HydroHelp 1TS for turbine selection;

– HydroHelp 2F for Francis units;

– HydroHelp 3I for impulse turbines; and

– HydroHelp 4K for Kaplan units.

In addition, two more programs are under development: HydroHelp 5PT for pump-turbines and HydroHelp 6UF for underground Francis turbines.

The user starts with HydroHelp 1TS, which determines the turbine type most suitable for the flow, head, and number of units desired in the power plant. The user then proceeds to the next program, based on the type of unit selected.

The next three programs guide the user through the design process, providing prompts regarding the options available and the best choice. The programs calculate quantities and costs for all work and electromechanical equipment. All data needed for these three programs can be derived from maps and a casual site inspection with a global positioning system (GPS) locator.

The programs calculate all basic structure dimensions, using such typical input data as length of pipeline, whether buried or above ground, length of tunnel, crest length of dam, and headwater and tailwater elevations. Parameters calculated include wave heights and the corresponding average rip-rap size on the dam, capacity of the powerhouse crane, and governor open-close times.

The programs include several safety overrides, such as preventing the use of too-small pipelines.

The CANMET Energy Technology Center is sponsoring development of the HydroHelp programs. Final versions were expected to be available by May 2007.


Hydropower Generation Report
Click here to enlarge image

null

HydroVision 2008 announces call for technical paper abstracts

HCI Publications, organizer of the HydroVision 2008 international hydropower conference and exhibition, is accepting abstracts for the Technical Papers program. The conference will be held July 14-18, 2008, in Sacramento, Calif.

Abstracts are requested on all topics of interest to technical professionals in the hydropower field. Preference will be given to abstracts that focus on innovative, practical, and proven technologies and methods.

Abstracts that describe the focus and content of proposed papers (maximum of 400 words) are due September 4, 2007. Submit abstracts through the Internet at: www.hcipub.com/ hydrovision/abstracts/asp.

All abstracts submitted will be reviewed by the conference Technical Committee. If accepted, authors will be invited to submit a paper by February 15, 2008, for inclusion in the official conference publication (in CD-Rom format) that will be distributed to all conference delegates.

– For more information, contact (1) 816-931-1311 or E-mail: hydrovision@ hcipub.com.

Assessing swim speeds with electromyogram radiotelemetry

Researchers from Pacific Northwest National Laboratory (PNNL) used electromyogram (EMG) radiotelemetry to estimate swimming speeds, and thus energy use, of chinook salmon migrating upstream past 1,090-MW Bonneville Dam.

This technology has been used for more than a decade to examine swimming behavior and energy use. However, the work at Bonneville represents the first time the technology has been employed in association with a large hydroelectric project, says Richard S. Brown, research associate with PNNL.

Captured fish are surgically implanted with EMG transmitters in their red muscle tissue. The signals from these transmitters are then calibrated against the swim speed of the fish in a swim chamber. Fish are then released into the tailrace of the dam. Researchers radio-track the fish as they move through the tailrace, fishways, and forebay of a dam.

The calibration relationships are used to convert EMG signals into estimates of swim speed. By using the relationship between oxygen consumption and swim speed, the swim speeds are expressed as measures of aerobic energy use.

Data collected using EMG radiotelemetry can be used to identify potentially difficult areas at a hydro project for fish to pass. At Bonneville, data showed the spring chinook swim significantly faster in the tailrace than they do through the fishway or the forebay. Average swim speeds in the tailrace were 106.4 cubic meters per second (cms), compared to 84.9 cms in the fishways and 80.2 cms in the forebay. Researchers determined that the higher swimming speeds and energy use rates in the tailrace at Bonneville are likely associated with generally higher velocities in the tailrace than in other areas and with problems finding the fishway openings.

In addition, research at Bonneville showed that it took fish 7.14 times longer to pass fishways than forebays. Areas such as sharp bends or corners showed variations in energy used that could cause delays in fishway passage.

With this information, project owners can look toward modifying areas so that migrating fish use less energy to pass the project. This, in turn, could increase the likelihood that the fish will reach the spawning grounds.

For example, researchers concluded that adding structures in the tailrace at Bonneville that allow fish to rest as they approach the dam may decrease energy use and delay. These structures could be placed in a way that would guide fish toward the entrances to fish ladders.

– For more information, contact Richard S. Brown at (1) 509-376-5002; E-mail: rich.brown@pnl.gov.

USSD releases report on spillway erosion

The United States Society on Dams (USSD) announces a new report, Erosion of Unlined Spillways. This report is the result of work by the USSD’s Committee on Hydraulics of Dams to compile information on the current state of knowledge on the causative mechanisms of erosion on unlined spillways and the ability to predict the occurrence and magnitude of scour using models.

Chapters in the 183-page report, published in June 2006, cover:

– Fundamentals of unlined spillway erosion;

– Four methods to predict scour: Annandale’s erodibility index, the U.S. Department of Agriculture’s erosion model, the U.S. Army Corps of Engineers’ REMR method, and Bollaert’s comprehensive scour model from the Swiss Federal Institute of Technology;

– Maintenance and remedial measures; and

– Monitoring and evaluation.

In addition, five appendices provide case studies of dams in Kansas, Iowa, Montana, Arizona, and Virginia that have suffered incidents of spillway erosion.

– The report costs $32 for USSD members and $52 for non-members. To order, visit www.ussdams.org/pubs.html.


To access this Article, go to:
http://www.hydroworld.com/content/hydro/en/articles/hr/print/volume-26/issue-3/departments/tech-briefs.html