A
majority of the wind farms in the United States use 2.5 megawatt wind
turbines, and recent technology has introduced even larger turbines
at 5 megawatts. Europe, on the other hand, is racing ahead of the
game with the largest
wind turbine yet - 10 megawatts. And it may be changing the
way wind turbines are designed altogether.
Europe
has seen a lot of advantages to building larger wind
turbines, such as avoiding environmental
issues by using larger turbines in deeper waters. There is
less of a risk of encountering environmental problems the further
offshore the turbines are located. Europe seems to build larger
turbines as the water grows deeper, as well.
Another
advantage to building larger turbines is the cost. The cost per
megawatt decreases as the the size of the wind turbine increases,
which is a helpful advantage when building a wind turbine that is
equivalent to a 30 story building in size.
The
533 foot tall wind turbine was designed by Sway,
a Norwegian turbine developer, and will have 476 foot long blades. Sway has
been working on the design since 2004, but the company is not working
on Europe's largest turbine alone. It is partnering with Norwegian
state utility Enova and
UK-based Clipper
Marine to bring the 10 megawatt monster turbine to life.
The
giant turbine certainly dwarfs the 2.5 megawatt and the newer 5
megawatt turbines being used now. In fact, it is so large that it
requires a whole
new offshore wind design.
The
new design does not attach the wind turbine to the sea floor like
smaller models. This 10 megawatt turbine, while giant in size, will
be lightweight enough to "sway" around a fixed base and
float in the ocean. It also has the ability to swivel on this base to
produce energy when the direction of the wind changes.
"This
is pioneering
stuff," said Feargal Brennan, head of offshore, process and
energy engineering at Cranfield University. "I believe 10MW
turbines are right on the limit of our knowledge; they may even prove
to be over the limit. We may find that they work for several years
and then start to develop problems. Will 10MW turbines still be
working after 10, 15, 20 years of operation?"
In
an attempt to answer that question, developers will use a smaller
turbine to test the fixed base design. This "smaller"
turbine will be 5 megawatts, which is still large in terms of what is
being used today. If the test proves that this new system will work
for the larger 10 megawatt wind turbine, this could be a new
beginning for offshore wind energy. These systems would be far enough
off shore to where they would not be noticed from land, send
electricity to land through cable lines at the sea floor, just like
internet cables.
While
Sway, Clipper Marine and Enova are on their way with this
development, they're not the only ones. According to other
reports, British company Wind
Power Limited has recently exposed the details its new 10
megawatt offshore wind generator, called Aerogenerator X. This unit
is expected to reach completion by 2013 or 2014, and will generate
enough electricity for 5,000 - 10,000 homes.
