Higher, bigger, and more reliable wind turbines are defining the future of offshore wind. Harsh environments demand the technology provider to come up with solutions that have high reliability and less maintenance requirements. It’s a journey GE started years ago, and it’s another example of how GE is helping customers build wind farms in some of the most challenging locations.
GE Power Conversion successfully completed manufacturing the first serial PMG in GE Renewable’s offshore wind factory in Saint-Nazaire, France, which was inaugurated in late 2014. The factory is set up to have a capacity of manufacturing 100 generators per year.
As the first series, 300 generators will be manufactured on-site. The first recently completed generator will be installed in GE’s Haliade™ 150-6MW-offshore wind turbine in Denmark. The turbine’s power yield is 15 percent higher than that of other same-generation wind turbines, each capable of supplying 5,000 households per year. The power supplied by these turbines will become increasingly cost-effective as the volume of generators coming out of the Saint-Nazaire factory increases.
This highly sophisticated production site uses the air-cushion system that has been implemented to move generators within the site. The innovative way of manufacturing eliminates the need of cranes within the factory, driving down the infrastructure costs significantly. The site is also equipped with a test bench, ensuring every generator coming out of the assembly line is ready to be deployed.
“The factory in Saint-Nazaire is the first offshore wind manufacturing site in France,” said Frederic Maenhaut, renewables executive for GE Power Conversion. “It is a milestone in the nation’s energy history. Now, by leveraging technologies from different GE businesses, we are well-positioned to bring clean offshore wind energy to the domestic market and export to regions beyond France where energy is needed.”
The 6-MW PMG is one of the world’s largest generators built to date. Its direct drive system has no mechanical gearbox coupled to the generator. Low component count increases equipment reliability and, therefore, enables higher energy efficiency, which also leads to increased turbine availability. Less downtime and maintenance requirements ultimately can reduce the cost of wind energy.
The generator is split into three electrical circuits. In the unlikely event of two circuits going offline, the high level of redundancy enables the turbine to continuously produce power, even in the “degraded” mode. This is a critical element for offshore wind power plants as stormy weather and treacherous water can delay repair work for days or weeks and result in a high maintenance expenditure.
“Offshore wind is gaining increasing competitiveness in the power mix, and GE is well-positioned to serve this industry,” Maenhaut said. “We developed this PMG technology five years ago. It is ideal for offshore setting, helping increase wind turbines’ availability and optimizing energy production.”
GE’s PMGs have been previously selected to be installed on Block Island, America’s first offshore wind farm, which will help generate 30 MW of electricity in 2016.
— Source: GE Power Conversion