Power output of offshore wind farms in relation to atmospheric stability

Title

Power output of offshore wind farms in relation to atmospheric stability

 Author

Alblas, L.
Bierbooms, W.
Veldkamp, D.

Faculty

Aerospace Engineering

 Department

Aerodynamics, Wind Energy & Propulsion

 Date

2014-12-31

 Abstract

Atmospheric stability is known to influence wind farm power output, by affecting power losses due to wakes. This research tries to answer what atmospheric stability does to the power production and how conventional simulations using the Jensen wake model compare and can be improved. Data is used from two offshore wind farms, Egmond aan Zee (OWEZ) and North Hoyle. Stability distributions are determined using metmast data. By combining this data with the production data, the influence of stability on the power output is studied. It is found that very unstable conditions result in higher power output (i.e. smaller wake losses) than near-neutral conditions, and these again show higher power output than during very stable conditions. Differences in normalized power output of 10-20% exist between the very unstable and very stable conditions. Simulations can be improved by adapting the wake decay constant (WDC). Observed WDC values are k TI, as opposed to the conventional k= 0.5TI. A hypothesis for further research is proposed regarding the influence of vertical turbulence.

 To reference this document use:

http://resolver.tudelft.nl/uuid:eb1f40f8-a5fa-4a9d-8018-321a554f1879

 DOI

https://doi.org/10.1088/1742-6596/555/1/012004

 Publisher

IOP Publishing

 ISSN

1742-6595

 Source

Journal of Physics: Conference Series 555, 2014

 Part of collection

Institutional Repository

 Document type

journal article

 Rights

(c)2014 The Authors
Published under the terms of the Creative Commons Attribution 3.0 licence
Files
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