WINDENERGY MAGAZINE 02 2018

INTERVIEW
THE IJMUIDEN VER AREA IS LARGER THAN THE ONES
CURRENTLY BEING DEVELOPED: 4,000 MEGAWATTS
INSTEAD OF 700 MEGAWATTS IN THE OTHER AREAS,
AND IT IS LOCATED 100 KILOMETRES FROM THE
COAST. DO MORE REMOTE WIND FARMS POSE A
BIGGER TECHNICAL CHALLENGE?
“Because it is further out at sea and a lot more
electric power is involved, we have to switch from
alternating current to direct current technology.
Alternating current creates a lot of power loss in
the cable, and those losses increase with the length
of the cable. For that reason, and because of its
size, IJmuiden Ver will be connected using direct
current.
Three more 700MW wind areas that have been
designated by the Ministry of Economic Affairs and
Climate are located more closely to the coast. The
wind farms to be built there can still be connected
using alternating current, which we will be doing
with three more standardized platforms. This provides
us the time up to 2027 to further develop our
concept for IJmuiden Ver.
A larger wind area also allows you to think
bigger. The offshore platforms have to be bigger
to facilitate the conversion from alternating to
direct current. This means the platform would
have to be three times the size of the one we are
currently using for alternating current. We have
looked into the idea of constructing an island to
see if that would be cheaper. An island allows for
more flexibility and also the space to install, for
example, power-to-gas installations, provided that
development pushes through. You could also build
living quarters for wind turbine technicians. You’re
basically creating a near-shore environment. Everything
could be built there instead of building it at
shipyards and then shipping it out to sea.”
AN ENTIRE ISLAND IN THE MIDDLE OF THE NORTH
SEA? HOW FEASIBLE ARE THOSE PLANS?
“We are still performing a study to see what is really
the smartest solution. There are also non-technical
issues that need to be considered. The permits,
the environmental studies, all those things need to
be taken care of. And then add the time it takes to
build the island. We estimate that in 2027 we could
have the first wind energy running via the island.
The government is also charmed by the idea, and
we absolutely think this is a feasible solution. There’s
already quite a power struggle going on over
who gets to be mayor of the island!”
RECENTLY THINGS GOT A LITTLE TENSE WHEN ON A
CLOUDY, WINDLESS DAY NOT ENOUGH ELECTRICITY
WAS BEING GENERATED TO SATISFY DEMAND.
TENNET HAD TO INTERVENE BY QUICKLY IMPORT
MORE ENERGY FROM ABROAD. WILL THE LARGER
SHARE OF WIND ENERGY IN THE FUTURE MAKE IT
EVEN HARDER TO GUARANTEE THE LIGHTS WILL
ALWAYS STAY ON?
“Energy producers have to inform TenneT how
much they expect to generate. Based on weather
forecasts they can predict this very well. We are
responsible to ensure the right balance at the end
but the market will need to determine how much
they are likely to generate in upcoming days. When
PV producers inform us they will be supplying
1,000 megawatts and in the end they only come up
with 800 megawatts, then they will be presented
with a hefty bill for that lack of 200 megawatts.
They are the first ones to have a problem.
Things will become more dynamic, but the market
will have to be ready and anticipate. The grid needs
to retain a certain flexibility. Wind and solar are
quite complementary. In the summer there often
is less wind but more sunshine, and during winter
time it’s the other way around. The energy sector
will have to look into energy storage to mitigate
those highs and lows. The backups could be plants,
but also contracts with energy suppliers abroad,
or batteries, of which a large one was opened last
week in the north of Germany. Hydrogen is also
looked into, as well as using batteries in electric
cars. Those could also be used to mitigate peaks.
The Netherlands already have quite a few existing
connections with other countries, so we can get
more power from abroad. But if there’s an unbalance,
the energy suppliers will have to foot the bill.”
CV
Frank Wester is senior manager Asset
Management Offshore. He is with TenneT
since 2007. Before that he worked for KEMA
in Arnhem and utility Nuon.
Wester studied electrical engineering at
Hogeschool InHolland and Delft University
of Technology. In 2004 he got his Ph.D. on
diagnostics of electric cables.
DC cables for offshore wind farm alpha ventus, Germany. All photos courtesy of TenneT
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