By Rikki Stancich in Paris

One year, almost to the day, after Statoil’s ambitious idea for a floating turbine was first conceived, the Hywind tower was being erected some ten kilometers off the southwest coast of Norway.

That was last year in May. By late September 2009, the world’s first full-scale deepwater floating turbine was delivering electricity to the grid.

While the Hywind turbine is already generating power, its main objective is to test the impact of wind and waves on the structure, over a two-year period. The results have so far been promising, indicating the concept of floating turbine technology to be viable.

This is extremely significant for those countries with deepwater coastlines, such as Greece and Portugal, for which offshore wind was previously considered impossible.

WindEnergyUpdate speaks to Statoil ASA’s Sjur Bratland about how floating turbine technology could be made cost competitive and where the key markets for deepwater offshore wind lie.

WindEnergyUpdate: The costs involved in the Hywind project were relatively high, given that it was the prototype. Have you identified any areas for cost reduction that would make the floating foundations a commercially viable option for other projects?

Sjur Bratland: With regards to cost issues, we share more similarities with bottom fixed foundations than we had previously thought. At the end of the day, why should we be that different in costs? Except for the fact that floating platforms use mooring lines, while bottom fixed use foundations. 

The US$75 million that it cost to get Hywind in the water is more representative of our confidence in the technology, rather than an indication of the actual cost. It really is a matter of scale – the operating cost and capital expenditure will  certainly come down with volume. We shouldn’t have any problem being cost-competitive with at least 20–25 metre bottom-fixed foundations.

We are always looking for ways to reduce costs. Better access and lighter turbines could reduce costs.

WindEnergyUpdate: The Hywind floating turbine foundation is suitable for water depths of between 120 and 700 metres. What level of demand is forecast for floating turbines in coming years and from where?

Sjur Bratland: Today, the demand is not yet there because until now, deepwater wind farms simply were not an option

But that is not to say that the market will not be there. If Greece, Portugal, Turkey, France,  Spain, Malta Egypt, Norway or Italy want to exploit their large offshore wind potential, then the market is there. The fact is that floating turbines in deep water is the only option for some countries when it comes to offshore wind.

We are asking around, visiting a lot of countries and exploring where and whether deepwater offshore wind is a possibility. There is certainly a lot of interest.

Hywind is still in its 2-year demonstration phase, but we are already touting for business. There are no sites to apply for as yet, but we are in conversations with governments. There is one such project under discussion in Scotland, and one in Maine, USA. Hopefully Asia could follow later.

Currently we don’t have capacity to do more than two or three projects, since  we already have so much on our offshore wind plate at present.

WindEnergyUpdate: Such depths usually imply a greater distance from shore. Given that the costs of the wind farms increase as the distance from shore increases (due to more expensive floating foundations, greater cabling distances, O&M crew accommodation requirements and crew transportation costs etc), are such wind farms commercially viable? 

Sjur Bratland: It is not necessarily the case that deep water implies greater distances from shore. Also, if you consider some of the 3 round projects in UK, the distance to shore issue is shared by fixed foundation wind farms.

Floating turbine or offshore O&M is a new concept; you need to think differently you need to do more preventative maintenance and less corrective.

WindEnergyUpdate: While the performance reports since the installation of the Hywind floating turbine have been very good, have you identified any technical aspects that could be improved?

Sjur Bratland: One of the main things we have learned is that we can’t implement all the oil & gas standards. We need to understand contractual and statutory issues and do as much onshore commissioning as possible. Having the cable installed at the same time as the turbine is advisable.

Standards to need to be established, but they should be established over time. We don’t want to set the wrong level of standards 

I think the main learning was when working offshore, that you need to plan properly; you need to understand the risk and that the risk is yours alone; and that we need to find a cheaper way to doing things. This need to been to done with the whole industry, we need to learn to work smarter together.

To respond to this article, please write to the Editor:

Rikki Stancich: rstancich@gmail.com