Speaking to Windpower Monthly, project manager Torgeir Nakken said that the Norwegian energy company expects to receive the go ahead for the trial by next summer.
The company will then be able to make an investment decision and finalise plans and start onshore construction in the fourth quarter of 2015. Offshore construction is due to begin in 2016, with commissioning set for 2017.
Nakken said that the company intends to qualify for the ROC subsidy scheme, which has a special provision for higher payments for floating projects. However, this is due to expire at the end of March 2017.
Qualifying for this provision is essential for the commercial viability of the project, Nakken said: "This is a strategic project, it's not a totally commercial, but that kind of commercial payment is necessary to take the decision to mobilise the project."
The project is notable as it will be the first floating project to consist of multiple turbines.
Statoil has now completed the geotech surveys of the seabed which Nakken said confirms that suction anchors can be used for the project. It has also secured a grid connection, signing an agreement for a connection at Peterhead at the Grange substation.
He also revealed that Statoil will use a new method of assembly for the 6MW turbines and substructures. The 2.3MW demonstration turbine off Norway's coast was assembled at sea, but this will not be possible with the larger 6MW turbines.
"The substructure will be towed to a site near shore where there are deep sheltered waters and we will erect the turbine onshore on the quay and then lift the whole turbine onto the substructure. Lifting at sea with the kind of weight and the height would make it very difficult."
The whole structure will then be towed to the site 18 kilometres from the Scottish coast.
There is still uncertainty about exactly how this will happen, with Statoil reaching out to outside parties in July with a challenge to submit solutions to the technical challenge. Nakken said that the response has been strong with a high number of companies responding.
The project will feature five 6MW turbines, but the company is yet to choose a supplier.
"We are confident that a 6MW turbine will work on the floating platform. The principal of putting a turbine on a structure like that has been proven by our demonstration turbines. But of course that's the reason that we are only doing a demonstration project, we want to test that this will definitely work," said Nakken.
The mooring system will be different from the 2.3MW project, and the motion controller will have to be updated.
Talking about why Statoil chose to site the project in Scottish waters, Nakken said: "The potential for floating turbines is huge in Scotland. There are not as many conventional offshore wind sites in Scottish waters compared with England, there's a lot more deep water. The Scottish government has also acknowledged the need for floating turbines."
He also welcomed the announcement of a 50MW competitor floating project near to the Hywind site: "We need to establish a market for floating turbine so we very much welcome this other project. It's important to mobilise the supply chain for the floating market so people can see that this is actually happening."
