Determining the Optimal Vessel Fleet for Maintenance of Offshore Wind Farms
Today the offshore wind energy industry needs financial support to be profitable.
For offshore wind farms to be more competitive against other energy sources, the
costs must be reduced, and this may be achieved by increasing the efficiency of
operation and maintenance. In this thesis operations research is used to develop
both a deterministic and stochastic strategic model to determine the optimal fleet
size and mix for doing maintenance, by taking stepwise development into account.
The results show that the deterministic model can solve problems of realistic
size for a planning horizon of 25 years in less than 23 minutes. The stochastic model
takes uncertainties in number of failures and weather conditions into account. The
computational study shows that a stepwise development of wind farms influence
the optimal fleet and is therefore important to take into consideration. The value
of the stochastic solution is significant and there is a benefit of having a stochastic
model compared to a deterministic one. The problem solver uses the Branch
& Bound method as solution strategy to solve the mixed integer programming
problem, and the Branch & Bound tree grows rapidly in size. An integer solution
is found fast, but it takes some time to prove that the optimal solution is found,
due to a flat solution landscape.
Place, publisher, year, edition, pages
Institutt for industriell økonomi og teknologiledelse , 2013. , 77 p.
IdentifiersURN: urn:nbn:no:ntnu:diva-23779Local ID: ntnudaim:8499OAI: oai:DiVA.org:ntnu-23779DiVA: diva2:685788
Hvattum, Lars Magnus, FørsteamanuensisStålhane, Magnus