Layout Optimization of Offshore Wind Farms affected by Wake effects, Cable topology and Support

118 Pages·2016·2.78 MB·English

by  Alvertos Maselis

Layout Optimization of Offshore
Wind Farms affected by Wake ef-
fects, Cable topology and Sup-
port Structure variation
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Faculty of Electrical Engineering, Mathematics and Computer Science

Layout Optimization of Offshore Wind
Farms affected by Wake effects, Cable
topology and Support Structure
variation
Master of Science Thesis
For the degree of Master of Science in Sustainable Energy Technology
at Delft University of Technology
Alvertos Maselis
October 9, 2016
Faculty of Electrical Engineering, Mathematics and Computer Science
IV
Alvertos Maselis Master of Science Thesis
Delft University of Technology
Department of
Wind Energy
The following members of the Thesis committee certify that they have read and
recommend to the Faculty of Electrical Engineering, Mathematics and Computer
Science for acceptance a thesis entitled
Layout Optimization of Offshore Wind Farms affected by Wake
effects, Cable topology and Support Structure variation
by
Alvertos Maselis
in partial fulfillment of the requirements for the degree of
Master of Science Sustainable Energy Technology
Dated: October 9, 2016
Supervisor: Dr. ir. Michiel Zaaijer
Thesis committee: Prof. dr Gerard van Bussel
Dr. ir. Michiel Zaaijer
Dr ir. Mark Voskuijl

Abstract
Aspartoftheefforttoreducethecostofoffshorewindenergy, thisMScThesisdealswiththe
layout optimization of an Offshore Wind Farm affected by wake effects, cable topology and
support structure variation. The main objective of the current MSc Thesis is to investigate
how important each of these aspects for the layout optimization is. The final outcome of the
project is an optimization tool that tries to find the optimal Offshore Wind Farm (OWF)
layout in terms of the lowest Levelized Production Cost (LPC).
This optimization tool depends on the analyzer algorithm, which calculates the objective
function of the optimizer. The analyzer consists of three different elements that are combined
togethersothattheLevelizedProductionCostwillbecalculated. Thus,theobjectivefunction
will be the LPC. The analyzer elements are the wake effects, cable topology and support
structure variation.
Forthesupportstructurevariation,partoftheMZTool[1]developedbyprofessorDr. Michiel
Zaaijer is used. Using this tool the support structure dimensions and costs can be deter-
mined. Regarding the cable topology, a hybrid approach[2] between Planar Open Savings
(POS)citekatsouris and Esau-Williams (EW)[2] heuristics is used so that the performance of
EW can be improved for multiple cables and lower infield cable cost will be achieved. Finally,
the Jensen wake model is used in an algorithm so that the wake effects can be determined.
The output of that algorithm is the annual energy yield and the LPC.
The optimization tool is based on the Genetic Algorithm (GA)logic. The performance of the
optimization tool is evaluated both cost and time-wise by implementing four scenarios. In
these scenarios some parameters of the GA are changed so that the behavior of the optimiza-
tion tool can be examined.
Finally, different case studies, related to the seabed shape and to the three ingredients in
the analyzer, are examined. These case studies will show how the changes in the analyzer
can affect the optimality of an OWF. More specifically, it is found that all three elements
in the analyzer affect the layout optimization. In addition, it is concluded that the support
structure variation has the largest contribution to the layout optimization compared to the
cable topology. Regarding the computation time, it is higher in the case that there is support
structure variation, since it takes more time for the analyzer to calculate all the costs.
Master of Science Thesis Alvertos Maselis
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Alvertos Maselis Master of Science Thesis
"I’ve learned in my life that it’s important to be able to step outside your comfort
zoneandbechallengedwithsomethingyou’renotfamiliaroraccustomedto. That
challenge will allow you to see what you can do."
— J.R.Martinez —