EYA – Energy Yield Assessment
Kjeller Vindteknikk provides energy yield assessments for developers, banks and private equity institutions. Our long experience and expertise in the assessment of wind farm projects in Norway, Sweden and Finland means we are well recognized by banks and financers investing in the Nordics.
We have carried out bankable energy yield assessments for more than 20 years. In that period, we have conducted EYAs for 200 wind farms both in the Nordics and internationally, with more than 5000 MW of installed capacity in total.
Our state-of-the-art EYA methodology includes the following steps:
- Control of the documentation of all measurement equipment, calibration and verification of compliance with IEC and MEASNET guidelines.
- Analysis of the wind resource at the measurement position resulting mean wind speed, wind rose, and wind frequency distribution.
- Ambient turbulence intensity and wind shear at the mast location. The wind shear is used to vertically extrapolate the wind conditions to the planned wind farm hub height(s).
- Long-term correction of the wind measurements, usually using our in-house KVT mesoscale WRF data.
- Horizontal extrapolation of the wind conditions, using CFD or linear flow models depending on terrain complexity.
- Production loss assessments, which can include KVT’s IceLoss model for detailed icing loss calculations.
- Net Annual Energy Production (AEP) calculations with uncertainty estimation. Net P50, P75 and P90 AEP will be delivered.
The calculation can be performed for a range of layout, hub height and turbine type scenarios, if needed. A range of additional tasks can be ordered, such as layout optimization, noise calculations and special loss assessments.
The wind measurement analysis can be performed for both meteorological masts, lidars and sodars.
The results are presented in a report subject to a comprehensive quality control according to our quality assessment system. The report may be written in Norwegian, Swedish, Finnish or English.