1 / 13

Fabrizio Magni magni.fabrizio@gmail

Study of extreme wind speed. for italian wind farm sites. Mattia Boccolini mattia.boccolini@garradhassan.com. Fabrizio Magni magni.fabrizio@gmail.com. Christof Stork christof.stork@garradhassan.com.

neveah
Download Presentation

Fabrizio Magni magni.fabrizio@gmail

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Study of extreme wind speed for italian wind farm sites Mattia Boccolini mattia.boccolini@garradhassan.com Fabrizio Magni magni.fabrizio@gmail.com Christof Stork christof.stork@garradhassan.com EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork

  2. Study of extreme wind speed Targets: for italian wind farm sites • To assess the validity of three different codes to estimate extreme wind speed; • To identify factors that improve extreme wind speed predictions; • To compare directional roughness length and extreme wind speed values; • To compare the whole data set and the data subset analysis results EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 02

  3. Study of extreme wind speed Wind shear evaluation: for italian wind farm sites • Analysis of anemometer data; • Roughness length calculation; • Time average calculation; EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 03

  4. Study of extreme wind speed Wind shear evaluation: for italian wind farm sites Difference between global and sector results Some errors in extreme wind speed evaluation EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 04

  5. Study of extreme wind speed Extreme wind speeds evaluation: for italian wind farm sites Methods Codes • Standard Gumbel (SG); • Eurocode 1 (EC1) • Modified Gumbel (MG); • Testo Unitario (TU) • Improved Independent Storm (IMIS); • Old Italian Code (DM’96) • Gumbel-Bergström (GB); Too short observation period [m] EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 05

  6. Study of extreme wind speed Aspects involved in result accuracy: for italian wind farm sites • Extreme wind speed evaluation techniques; • Amplitude of data sets; • Number, height and precision of anemometers; ; • Accuracy of Roughness length evaluation EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 06

  7. Study of extreme wind speed Extreme wind speed evaluation techniques: for italian wind farm sites Percentage difference between code predictions and data results [Err %] [Err %] EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 07

  8. Study of extreme wind speed Amplitude of data sets: for italian wind farm sites Less accuracy • SG, MG : 1 value/year Involved data Errors sensitivity • GB : All data recorded • IMIS : ≈ 100 values/year Good accuracy Extreme wind speed in Campania using data subset EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 08

  9. Study of extreme wind speed Number, height and precision of anemometers: for italian wind farm sites Campania Data set: Roughness lenght evaluation z Few anemometers, too close to each other and to the ground Large errors in wind shear evaluation V EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 09

  10. Study of extreme wind speed Accuracy of Roughness length evaluation: for italian wind farm sites Accurate evaluation of extreme wind speed EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 10

  11. Study of extreme wind speed Wind speed amplification coefficient: for italian wind farm sites Exact roughness length Measured roughness length • It is important: • to measure roughness length carefully • to choose accurate time averaging value EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 11

  12. Study of extreme wind speed Return Period dependence: for italian wind farm sites • TR dependence formula (EC1, TU, DM’96); a • TR dependence formula (SG, MG, IMIS, GB); TR ACCURACY OF THE EXTRAPOLATION EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 03 Slide : 12

  13. Study of extreme wind speed Concluding remarks: for italian wind farm sites • More extensive study in terms of number and spread of masts as well as longer observation periods should be performed to draw robust conclusions EWEC 2007, Milan, 8 May 2007 - Boccolini, Magni, Stork - Slide : 03 Slide : 13

More Related