Mothership

A mother-ship is a vessel that can allocate several technicians/engineers and also small transfer boats, while staying near far offshore wind farm. Some of the mother vessels are designed in such a way that a large storage space is provided. A helicopter landing space could also be included. According to Neil Patterson from OSD-IMT “Crew change and supplies will be carried out using a dedicated support vessel with the option to carry out crew changes by using large helicopters normally associated with servicing offshore oil installations” [17]. The aim of using mother vessel is to, most importantly, provide a secure ‘shelter’ for engineers working offshore. By using mother vessel, engineers do not need to spend most of their days being transfer between onshore base and the wind farm. That means that more tasks could be performed as working time is used more effectively. That also means that technicians have better chance to successfully use favorable weather conditions when possible [17].

Advantages

• Transit time is reduced i.e. working time increases

• Withstands higher waves

• Possible to access wind turbine directly

• Comfortable living space for technicians

• More stable than smaller vessel, i.e. possibility of sea sickness decreases

• Small storage space available

• Possible to use in deeper waters

• Could be shared between wind farms/operators

• Reduction of non-operation downtime [17]

• Increased turbine availability [17]

Disadvantages

• Large replacements cannot be performed

• Mooring points has to be determined for each location