Title: Modelling of offshore wind resources. Comparison of a meso-scale model and measurements from FINO 1 and North Sea oil rigs.
1Modelling of offshore wind resources. Comparison
of a meso-scale model and measurements from FINO
1 and North Sea oil rigs. by 1Erik Berge,
1Øyvind Byrkjedal, 1Yngve Ydersbond and 2Detlef
Kindler 1Kjeller Vindteknikk AS, 2Windtest
Kaiser-Wilhelm-Koog GmbH
2Aim of the study
- Validate meso-scale models for calculation of
offshore wind conditions - In particular, validate model derived vertical
wind profiles in the marine boundary layer - The study is a part of the NORSEWIND project on
developing Wind Atlases for the Irish Sea, North
Sea and Baltic Sea.
3Meteorological model WRF Weather Research and
forecast model set-up
2 km resolution
6 km resolution
18 km resolution
4Model set-up
- NCEP boundary data every 3 hour
- WRF-runs for 27 hours covering 1 day
- Model runs for all three domains for four
complete years (2004-2007) - Data stored hourly in every grid-point for all
model layers
FINO 1
5Measurements from the FINO 1 plattform
6Measurements
- 10 min. data available for the period 2004-2007
- Wind speed-data corrected for mast effects by use
of the Lidar
7Annual and monthly averages
WRF yields 0.2 m/s lower annual average Hourly
correlation is 0.92
8Wind roses and Weibull distributions
WRF
FINO 1
9Vertical wind shear and temperature differences -
January 2004
10Average vertical wind shear based on model and
measurements
11Wind speed measurements at North Sea oil rigs
Sleipner platform
12Comparison of platform measurements with the
WRF-model
Height of meas. Observed average WRF average WRF average Hourly correlation
Troll 94 m 10.9 10.4 - 5 0.90
Gullfaks C 142.5 m 11.8 10.7 - 9 0.90
Sleipner A 136 m 11.8 10.7 -10 0.91
Ekofisk 100m 10.9 10.3 - 5 0.91
Height Observed average WRF average WRF average Hourly correlation
Fino 1 100 m 10.04 9.87 - 2 0.92
13Summary and conclusions
- An offshore wind analysis carried out in the
framework of NORSEWIND - Long-term average wind speed very well predicted
by meso-scale model WRF at FINO 1 ( 2 deviation
over 4 years). - Some deviations for modelled wind shear
WRF ?100-600.08, while obs ?100-600.06.
Uncertainties also larger in obs wind shear. - Wind shear clearly linked to atmospheric
stability.
14Summary and conclusions cont.
- Model data indicate that oil rig annual average
wind speed data could be overestimated by 5-10. - Focus will be given to further assess the wind
profiles, oil rig data and the meso-scale model
data within NORSEWIND by use of LIDAR
measurements, satellite data etc.