Eize de Vries has spoken to Anders Søe-Jensen, CEO of GE’s offshore wind unit, at the EWEA 2015 event in Paris, where the company introduced its new Renewable Energy business, following the acquisition of Alstom’s power and grid businesses .
GE Offshore Wind’s brand new nacelle factory in St Nazaire is currently manufacturing five Haliade 150-6MW turbines for the US Block Island project. This represents a stepping-stone to an over 2GW order backlog for major projects in the US, France and Germany, according to Søe-Jensen.
He also spoke frankly about a serious generator issue, which impacted both the onshore prototype in France and the second offshore prototype added to the Belgian Belwind offshore wind farm.
Not long after the second direct drive offshore prototype was installed, a major generator issue was discovered in both turbines. The reason turned out to be a glue bonding issue at some of the 256 magnets carriers.
Søe-Jensen explained: “While the issue was easy to diagnose with the magnets becoming loose and separating from the carriers, it took us some time to establish the root cause. This process involved the consultation of glue experts at universities, technology institutes and in industry, amongst them Airbus. Once the root cause was established and the solution was worked out and validated, we commenced rectifying the issue. I am proud that we rebuilt the offshore generator without requiring crane vessels, but by simply relying on service vessels and additional helicopter staff transfer support.”
He added that, since going back into active service, the offshore turbine operated for a two-month period with 99% availability and that there were a number of windy days with about 80% capacity factor.
Perceptions about GE’s commitment to the offshore wind industry have been questioned. Soon after purchasing Enron Wind in 2002, the US giant employing 360,000 people worldwide, stepped in the offshore wind market with a 3.6MW turbine used at the Arklow Bank project. However, despite announcing a product upgrade with enlarged 111-metre rotor, they stepped out.
GE then bought ScanWind in 2009 and upgraded/redesigned this direct drive turbine (with its ring generator positioned behind the tower) into a 4.1MW GE 4.1-113 model. Following a successful prototype testing, the plug was pulled again.
Søe-Jensen said that the situation for GE is totally different this time: “With today’s knowledge, Arklow Bank can perhaps be best described as a painful experience. The GE 4.1-113 was too small and arrived too late, and without an order pipeline. It was therefore in my view wise-fully to withdraw.”
He elaborated further that the Haliade is a dedicated state-of-the-art offshore turbine, which has proven its capabilities for several months in a row now. Furthermore, the 30MW Block Island is the first offshore wind farm in the US and fully bank-financed, which also applies for the German Merkur offshore wind project comprising 66 turbines.
Søe-Jensen said: “This time there is finally a firm total order backlog in excess of 2GW, giving us the No. 2 largest position in the world behind Siemens.”
The new nacelle facility has been producing wind turbines for Block Island since it was inaugurated in December last year. Further orders for a total of 238 turbines destined for French projects will commence as soon as the orders become final and signed. Søe-Jensen described the factory itself as “purpose built for lean serial production of dedicated offshore turbines”.
On the future of the current Haliade turbine platform and possible future further scaling he said: “The 6MW Haliade is designed for the lowest possible LCOE. To drive this further down there is a choice between going bigger or to reduce costs, and utilities and other customers generally want both. The current offshore top range is 6 – 8.5MW, with a possible ceiling at around 10MW.
“Monopiles are still the most cost-effective solution. I see major limitations in further stretching diameters beyond the large ‘Monopile Heavy’, not to speak of even larger sizes to suit future turbines in excess of 10MW. Additional potential limiting issues might occur regarding suitable installation ships with sufficient crane capacity and for jacket stowage.”
Article by Eize de Vries