Sodar, Remote Sensing, and Triton Explained: Articles, Technical Reports, Conference Papers, and Independent Research

Seeking A Data Model To Match Turbine Advances

Second Wind CEO Larry Letteney explains how as turbines become more innovative, wind resource assessment must also. The article outlines how a new wind data model can be a strategic asset for wind farm developers as the industry evolves.

This article appears in the printed version of North American Windpower. More

A Higher Height Data Wakeup Call

Reaching higher heights is the industry's future. This article details why remote sensing systems, with their ability to measure wind at higher heights, play a key role in project energy estimates.

Susan Giordano, in Renewable Energy Focus, September/October 2010 [link to e-book, turn to page 16]

Sound Intelligence in the Search for Wind Power

An overview of sodar and its expanding use in the commercial wind industry."The wind industry’s need for wind measurement has grown beyond the 60-m reach of standard meteorological masts. To reduce uncertainty for wind projects that can cost anywhere from $100 million to $1 billion, the industry needs data from the entire rotor sweep that can’t be gleaned from 60, 80, or even 100-m met masts."

Susan Giordano in Windpower Engineering, October 11, 2010 [link to website]

Wake Up and Smell the Wake Effects

What are wake effects, why are they important to the wind industry, and how is remote sensing technology helping?

Naomi Pierce in North American Clean Energy, August 2010 [link to e-book, turn to page 31]

Eliminating Uncertainty with SoDAR

Susan Giordano, in WindSystems, February 2010 [PDF]
This article appeared in the Feburary 2010 issue of Wind Systems Magazine and is displayed with permission.

Wind Resource Assessment and Extreme Shear Events

A shear event is a short period of extreme shear. These events can have an impact on the suitability of wind resource at a site, and this article explains a simple way to characterize how often shear events occur at a site. "Remote sensing technology, such as Sonic Detection and Ranging (sodar), has made it practical to obtain accurate measurements of wind speed and direction at several heights across the swept area of a typical wind turbine rotor. However, obtaining a large number of values for wind speed and directional shear over an entire measurement campaign can result in an unwieldy amount of data and make it difficult to draw conclusions. This article describes a simple technique for plotting the frequency of shear occurrence in order to highlight site-to-site differences that would affect wind turbine performance and reliability."

Niels LaWhite, Liz Walls, and Ken Cohn, in WindTech, July / August 2009 [PDF]
This article appeared in the July/August 2009 issue of WindTech International and is displayed with permission. Copyright 2009 by Siteur Publications.

Viability of Sodar for Long-Term Resource Assessment

An initial assessment of the viability of sodar in wind resource assessment applications. "This article reports on data from customers using Second Wind’s Triton sonic wind profiler in eight diverse locations. The findings show reliable reporting of valid wind data at heights that encompass the full blade sweep of commercial wind turbines. Gross data recovery was above 95%, correlation to anemometry at 60 metres was 0.97, and signal-to-noise ratios were greater than 9 at heights up to 160 metres.

by Liz Walls and Walter Sass, in WindTech, September 2008 [PDF]
This article appeared in the September 2008 issue of WindTech International and is displayed with permission. Copyright 2008 by Siteur Publications.

SoDAR Takes Assessment to New Heights

Describes recent improvements to sound detection and ranging (SoDAR) technology which enable sodar to be used in wind profiling and resource assessment applications.

Susan Giordano, in North American Wind Power, February 2008 [PDF]

The Technology of the 200-Metre Met Mast: Rethinking Sodar for Wind Site Profiling

"Accurate assessment of the resource at potential wind-energy sites is becoming more critical. The 60m met towers most commonly used for site assessment are decreasingly effective as turbines grow taller.
Sodar devices, which measure wind speed and direction at any height up to about 200m, are a potential solution."

Walter Sass, in WindTech, September 2007 [PDF]
This article appeared in the September 2007 issue of WindTech International and is displayed with permission. Copyright 2007 by Siteur Publications.

Independent Laboratory Reports

Energy Research Centre of the Netherlands, 2009: Comparative measurements between
a Triton SODAR and Meteo Measurements at the EWTW, The Netherlands
National Renewable Energy Laboratory, 2010: Comparison of Second Wind Triton Data with Meteorological Tower Measurements
Second Wind (Liz Walls), 2009: Sample Triton Correlation Study and Performance Update

Independent Academic Research

Forecasting of Wind for Energy in Southern Idaho, by Kevin Nuss, Paul Dawson, and Todd Haynes
Boise State University College of Engineering. "As part of a research project aimed at improving forecasted wind speeds for the purpose of making wind energy more usable, various physics options in WRF were investigated. These were compared to readings from a Triton sodar placed on the site of an operational wind farm in southwest Idaho, on the Snake River plain...." PDF >

EWEC 2010: Walls et al., "Quantifying the Uncertainty in AEP Estimations using SODAR" Paper PDF Poster PDF

EWEC 2010: Hastings-Black et al., "Atmospheric Absorption and SODAR Performance" Poster PDF Paper PDF

EWEC 2009: Walls et al., "Sodar and Extrapolated Tower Wind Shear Profile Comparison in Various Topographic Conditions" (PDF)

Windpower 2009: LaWhite et al., "Characterizing Wind Speed and Direction Shear with SoDAR Data" (PDF)

EWEC 2009: LaWhite et al., "Sodar Measurements During Periods of Precipitation: Results of New Rain Rejection Algorithm"(PDF)

AWEA Asset Management Conference, 2009: "New Remote Sensing Options for Performance Measurement and Optimization of Wind Turbines" (PDF)

AWEA Wind Resource Assessment Seminar, September 2008 (PDF)