Dutch Build Towering Wind Turbines Out at Sea
NETHERLANDS: September 4, 2007
IJMUIDEN, Netherlands - There is no shortage of wind in the
densely-populated Netherlands but there is a shortage of space and in a
nation which likes its houses small and its gardens cosy, opposition to wind
farms is immense.
That is why a new Dutch wind farm is being built so far out to sea it is
barely visible on the horizon, reducing the visual impact of its 60 turbines
to virtually nil whilst at the same time harnessing higher offshore wind
speeds.
Offshore wind farms are likely to appear more and more frequently off
European coastlines as governments seek to increase their use of renewable
energy without angering their citizens by placing giant turbines on their
doorsteps.
The 383 million euro (US$522.3 million) Q7 wind park development, 23 km (14
miles) from the Dutch North Sea coast, is the farthest offshore wind park
anywhere in the world, and its developers Econcern and Eneco Energie say a
further five to 10 such wind parks will likely follow in the next few years.
"Q7 will contribute enough electricity for 125,000 households, but it is
also a learning process. We are learning how to build these wind farms, how
to organise the supply chain, and how to manage and operate them," said
Bernard van Hemert, one of the wind farm's engineering directors.
"Most campaigns against turbines are based around the noise and the visual
impact, and these have been reduced by going offshore. It is more expensive
to do it here than to do it on land, but we have all agreed we don't have
enough space on land," said van Hemert.
Blessed with shallow sandy soils around their coastline, Dutch engineers say
the foundations for the turbines can be hammered 25 metres (82 feet) into
the ground in just a matter of hours, although there are myriad other
challenges.
The proportions are breathtaking. The turbines extend about 98 metres (320
feet) from the ocean, with three sharp narrow blades, each 40 metres (130
feet) long.
It is hoped that when they start rotating in early 2008 they will cut
carbon-dioxide emissions by 225,000 tonnes, helping the Dutch to meet a
target of 20 percent renewable energy use by 2020.
TRICKY LOGISTICS
The turbines are so massive they can only be transported by sea and there is
just one factory in Europe which can weld and construct the
4.5-metre-diametre piles, which must be first driven into the sea to form
the base of the turbines, van Hemert explains.
"It is a huge logistical operation which requires lots of space. There are
only a few crane vessels which can handle those huge structures and hammer
them down."
"But bringing up the cables is the most challenging for all offshore wind
projects."
Expert divers are helping to fit the electrics.
Developers have also had to ensure that the wind park is well away from busy
shipping channels.
"Studies in the United Kingdom have shown that there can be some radio
interference but in the situation we have here it is completely safe and
there is no risk of confusion or reduced visibility for vessels."
Jim Mollet, chairman of a Dutch group campaigning against wind energy
acknowledges off-shore wind farms have some benefits over land-based wind
turbines.
"They can be a better solution. But the problem is people tend to believe
they are an entire solution. We think the vast sums spent on wind farms
would be better spent on research and innovation in other energy sources."
Wind farms cannot generate the sheer amounts of energy the continent
requires with cost or space efficiency, he added.
Story by Alexandra Hudson
REUTERS NEWS SERVICE
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