ROMO Wind and Vattenfall hereby offer you the opportunity to analyse and evaluate, in detail, the results of a comprehensive performance measurement project. Supported by the Danish EUDP program, the project was conducted from 1 November 2014 to 17 December 2015 in the Nørrekær Enge wind farm in Northern Denmark together with the wind farm owner, Vattenfall and DTU Wind Energy. It comprised a direct comparison between different wind turbine nacelle based wind measurement instruments as well as a correlation to an IEC certified met mast raised in front of one of the turbines in the wind farm. Data, collected from the met-mast, a nacelle lidar, the nacelle anemometer and the iSpin spinner anemometer was combined with power measurement and relevant meteorological data. In addition, iSpin power curves and other wind measurements were also recorded from all other wind turbines in the wind farm.
The entire wind farm performance data set is now available for free to European and US parties in return for signing a data sharing agreement. In exchange for the data set, the data receiver will simply agree to analyse the data and provide written feedback to Vattenfall and ROMO Wind within a pre-agreed timeframe and not to distribute to other parties.
The Nørrekær Enge wind farm, commissioned in 2009, consists of 13 Siemens SWT 2.3-93 wind turbines at 80 m hub height. The layout of the park is shown below together with the IEC compliant met mast:
Two complete data packages are available:
1. A data package from 1 November 2014 to 21 January 2015 for turbine no.4. During this period, data is available from the turbine nacelle anemometer SCADA data, from a WindIris nacelle lidar (placed on the nacelle roof), from the met-mast and from iSpin also including power measurement data as well as air density, air pressure and nacelle position.
2. A data package from 24 September 2015 to 17 December 2015 containing iSpin and power measurement data for all 13 turbines as well as the met-mast data.
Included within the data packages is a description of the various signals, wind tunnel calibration certificates, photos of the iSpin sensor installations, videos and other information useful for the verification of the data.
In summary ROMO Wind and Vattenfall when analysing the data reached the following conclusions:
• iSpin measured the power curve with approx. 30% less scatter than the nacelle lidar and the met-mast.
• When measuring the wind simultaneously in all wind sectors around all wind turbines, i.e. also in disturbed wind conditions such as in wake of other turbines, iSpin was still able to measure the power curves (see figure below) as well as yaw misalignment with high precision. This was done using the same calibration factors obtained from the reference turbine no.4, demonstrating that the factors are transferable to other turbines and stable even when the wind turbines are in the wake of other turbines.
• When measuring the wind simultaneously in all wind sectors around all wind turbines, nacelle lidar provided a highly variable power curve as well as yaw misalignment results when in the wake of other turbines.
• When measuring the wind simultaneously in all wind sectors, eliminating one outlier wind turbine NKE01 and a turbine with yaw misalignment NKE13, the remaining eight wind turbine power curves varied only 0.3% in Annual Energy Production (95% confidence level); “7, 8 and 9 are always in de-rated noise mode and not considered for this result”. Consequently, iSpin can be used to monitor the performance of the entire wind farm with very high precision.
• Lidar turbulence intensity measurements correlated poorly with the met-mast, whereas iSpin measurements correlated well.
If you are interested in receiving our data please fill out the below form and a member of our sales team will get back to you shortly enabling you to sign the data sharing agreement with Vattenfall and ROMO Wind.