Why Tall Towers?
Typically, wind data collection from 10 to 30 meter meteorological towers is used by a variety of weather prediction models to “guesstimate” UP to the hub height of today’s utility scale wind turbines. Or satellite data is used to “guesstimate” DOWN to boundary layer wind resources. Both forecasts can diverge appreciably from actual wind power availability and subsequent wind farm power output. These data sources were designed for aviation and consumer weather needs, not to support wind power development and integration. Thus surface and satellite data do not meet the need for actual wind resource information at turbine hub height and higher.
Tall tower wind data shows wind speed Increases with height
To address this gap in the availability of real time wind speed, wind direction, wind power, and wind shear values, WindPole has secured the only national tall, narrow face, communication tower portfolio capable of measuring at and above the turbine height/boundary layer.
Investors have become wary of developer’s financial projections because most wind farm output falls short of the forecasts. Not only cautions investors, but also developers, operators and power traders are demanding more accurate wind assessment data to meet rigorous due diligence. WindPole’s tall tower analysis has revealed that the actual hub height wind power can be 8.5% higher than the power output predicted by models. Actual data at 115 meters high was compared to extrapolated data at the same height using the standard wind profile power law (1/7th power law). A wind shear coefficient of 0.143 (1/7) was assumed for the model.
Actual wind power and wind speed data is important for two reasons. First, actual data could make more sites attractive for development. Second, real time wind data will lead to considerably improved energy assessment forecasts, which is critical for investors, power traders and other variable power market participants.