March 27, 2020 | by NRG Team Voices | Engineering + Technology
As turbines continue to grow taller, Lidar has emerged as a tool capable of providing cheaper, faster, and safer finance-grade wind measurements up to and including top-tip of even the largest wind turbines. Rugged and remarkably flexible, Lidar also performs well in a variety of environmental conditions, including cold weather.
With numerous Lidar technologies used for wind measurement today, it is fair to wonder which device is best suited for use in cold climates. ZX Lidars has spent a considerable amount of time analyzing how their Doppler Lidar technology, ZX 300, performs in clear-air, low-backscatter conditions typical of high latitudes (such as Scandinavia, Northern Canada) and high altitudes (European Alps, the Rocky Mountains in the United States).
ZX 300 is unique among Doppler remote sensors in that it uses continuous-wave technology rather than pulsed Lidar technology to capture wind speed data. As the name implies, the continuous-wave ZX 300 Lidar is constantly collecting data via an extremely high-fidelity, high-sensitivity laser design. The continuous emission waveform allows a higher average photon flux in the atmosphere, while the available signal is concentrated at a single measurement height, rather than shared across multiple measurement heights. This leads to two distinct advantages – constant and very high sensitivity at all measurement heights, including in clean air conditions, and the ability to measure at lower heights or ranges, down to 10 m.
In a clean air study carried out by ZX Lidars, ZX 300 was subjected to frigid temperatures that dipped down to -20°C, drifting snow, wind speeds gusting over 40 ms-1, and low visibility. ZX 300 Lidars were monitored across multiple sites, which revealed availability with > 90% quality checked at all heights.
This proves that ZX 300 is a reliable choice for wind measurement in regions that experience extreme cold weather conditions. ZX 300 can also be used to fill in data gaps when met masts experience lower availability in the winter months (e.g. through instrument freezing or extreme ice buildup on met mast causing larger flow distortions than international standards allow).
While campaign planning remains critical for all measurement devices, using continuous-wave Doppler Lidar can help reduce data availability risks significantly.
Please visit our ZX 300 product page to learn more about this technology.