Various parameters were considered when performing our initial analysis. However, it was decided that the most important variables were the number of wind turbines and the distance from the shore.
Other variables that were found as important were capacity of wind turbines (MW), work-shift of each technician (hrs), estimated cost of personnel (£/hrs), lifetime of a wind farm and also technical and financial aspects of the vessels.
In order to create a reliable EXCEL tool, a cost of CTV, mother vessel and jack up was estimated. For CTV- 2 types were considered:

  1. smaller vessel with an overall length of 14-18 meters

  2. larger one that can withstand higher wave heights with overall length of 21 meters For mother vessel we considered the overall length of 187 meters and for jack up 79.6 meters.

For each of the solutions we considered three cases:

  • Spot market

  • Long term charter (1 year)

  • Purchase

The costs were estimated based on the results from academic papers or on information from various industrial websites.
Once those costs were estimated, we considered the combination between different scenarios. For example, we considered a scenario when a jack up is purchased and CTVs are:

  • Rented at the spot market

  • Chartered for a long term

  • Purchased

That would give us 3 scenarios when considering just a purchase of a jack up. Hence, we considered all possible combinations for all possible options, which resulted in 21 potential scenarios.

Furthermore, the idea of sharing the costs was also introduced. The concept we had in mind was to show how the costs would change (for each solution) when there is more then one operator who decides to charter/buy a vessel. By using that alternative a company has a chance to see how the costs would change if the costs are shared between certain number of operators, and how that would be compared to the costs paid if the company decided to charter/buy a vessel on its own.