ZephIR Lidars industry-leading, turbine-mounted Dual Mode (DM) system has been deployed by developers Renewable Energy Systems Ltd. (RES) in a first-of-its-kind commercial investigation into lidar-generated turbine performance measurements.
This pioneering trial, which began in June 2013 and is expected to end in November 2013, uses a ZephIR DM installed on a Vestas V90 turbine. The ZephIR DM is uniquely capable of measuring upwind; wind speed, shear, turbulence and veer. The DM was chosen for its ability to provide absolute (traceable to IEC Standard 61400-12-1CD) and relative power curve assessments both hub-height and rotor-equivalent.
In non-complex terrain, current industry guidelines require measuring the wind at distances of two to four rotor diameters upwind minimising blade induction effects on the wind speed.
Complex terrain causes the wind model to evolve as it moves over the landscape approaching the turbine, meaning that the wind and available energy at the turbine rotor can differ significantly from the measurement point.
To combat this uncertainty, wind speed can be measured much closer to the turbine. Although these measurements are within the blade induction zone, their repeatability is higher and will be less influenced by the complex terrain. The ZephIR DM and ZephIR 300 are the only commercial lidar systems with the ability to measure at distances as short as 10m, and out to 300m.
With the ZephIR measuring at 135, 90, 45 and 10m ranges in its second phase, the trial exploits the DMs unique ability to measure short distances upwind of the turbine within complex terrain to produce power curves.
Ian Locker, ZephIR Lidars Managing Director, said: In this trial, the ZephIR Dual Mode is demonstrating its ability to take measurements that other lidars cannot. We are demonstrating with this trial that higher repeatability of turbine performance measurements can be made possible through deployment of the DM. Additionally, our system is helping RES, one of the most respected technical leaders in the wind industry, determine new and more reliable power curve measurement techniques for turbines, including those increasingly operating in complex terrain.
A spokesperson for RES said: The ZephIR DM was the perfect choice for this trial. Traditional methodologies for measuring power curves have practical and technical challenges. This trial has the potential to change current methodologies, address existing challenges and improve commercial relationships between developers, operators and turbine suppliers by better understanding the relationship between wind and turbine performance. As well being able to measure upwind at extremely short distances, no other lidar system was able to incorporate shear, turbulence and veer in absolute and relative power curves. The ZephIR DM is the only wind lidar device that satisfied our requirements for this trial.
Notes for Editors
About Zephir Ltd.
Celebrating 10 years of wind lidar excellence
In 2003 we released the first commercial wind lidar, ZephIR®, exploiting decades of research at UK government Research & Development establishment QinetiQ. Designed specifically for the wind industry ZephIR has paved the way for many of the remote sensing devices seen in the market today. Our original lidar technology continues to innovate with world firsts such as taking measurements from a wind turbine spinner and being the first to deploy an offshore wind lidar, both fixed and floating. ZephIR has also now amassed more than 3.5 million hours of operation across 650+ deployments globally spanning a decade of commercial experience. For wind measurements onshore, offshore and in turbine-mounted applications, ZephIR provides accurate, reliable finance-grade wind data.
Zephir Ltd. is a wholly owned subsidiary of Fred. Olsen Ltd. – established in the UK in 1963 with business interests primarily focussed on renewable energy, including ZephIR.
Visit www.zephirlidar.com for more information.
RES is one of the worlds leading independent renewable energy project developers with operations across Europe, North America and Asia-Pacific. At the forefront of wind energy development for over 30 years, RES has developed and/or built more than 7.5GW of wind energy capacity worldwide. In the UK alone, RES currently has more than 1GW of onshore wind energy either constructed, under construction or consented.
RES is active in a range of renewable energy technologies including large-scale biomass, solar, wave and tidal and on-site renewable installations. For more information, visit www.res-group.com.