Powering Europe - European Wind Energy Association

• Reduce dependency on gas and oil from unstable regions
• Transmit indigenous offshore renewable electricity
to where it can be used onshore
• Bypass onshore electricity transmission bottlenecks
2.competitionandmarket
• Development of more interconnection between countries
and power systems enhances trade and improves
competition on the European energy market
• Increased possibilities for arbitrage and limitation of
price spikes
3.Integrationofrenewableenergy
• Facilitation of large scale offshore wind power plants
and other marine technologies
• Enabling wind power and other renewable power’s
spatial smoothing effects, thus reducing variability
and the resulting flexibility needs
• Connection to large hydropower capacity in Scandinavia,
introducing flexibility in the power system
for compensation of variability from wind power and
other renewable power
• Contribution to Europe’s 2020 targets for renewables
and CO2 emission reductions
With the technology currently available, most offshore
wind power is being developed and expected in the
shallower waters of Northern Europe where the wind
energy resource is attractive. As a result, offshore grid
activities and plans focus mainly on the North Sea,
the Baltic Sea and the Irish Sea.
Growing a transnational offshore grid
from national initiatives
Most of the electricity grids in the world were built
bottom-up, connecting local producers to nearby offtake
points, and this will not be different with the offshore
grid. An offshore grid would take decades to
be fully built. Even implementing a single line can be
very lengthy (depending mainly on the permitting procedures).
A transnational offshore grid that interconnects
wind farms and power systems in a modular way
could be built in three main stages:
chApTEr 4 Upgradingelectricitynetworks–challengesandsolutions
StageI:Interconnectedlocal(national)grids
Countries connect offshore wind power to the national
grid. Point-to-point interconnectors are built in order
to trade between national power systems. Onshore
connection points for wind power are identified. Dedicated
(HVDC) offshore lines are planned and built by
TSOs to connect clustered wind power capacity. Dedicated
regulatory regimes are established for offshore
transmission, enabling TSOs to recover investments
via the national electricity market. In the meantime,
regulatory regimes are gradually becoming more internationally
focused. The necessary onshore transmission
reinforcements are identified. Preparations are
made for multilateral grid planning. In parallel, HVDC
VSC technology is developed and standardised at accelerated
speed.
StageII:transitiontotransnationalinterconnectedgrid
Grids are planned multilaterally. Long-distance lines
dedicated to offshore wind farms are planned and implemented.
Pilot projects for connecting offshore wind
power to different markets are implemented (Kriegers
Flak, super-node, COBRA). HVDC VSC technologies
are tested and optimised based on operational experience.
The locations of planned offshore interconnectors
are adapted to connect offshore wind farms. The
locations of planned wind farms are adapted so they
can connect to the grid via existing interconnectors.
StageIII:transnationalinterconnectedgrid
The transnational offshore grid is implemented step
by step. The planned lines are built. Where appropriate,
wind farms are interconnected and/or connected
to different shores.
In 2009, EWEA proposed its 20 Year Offshore Network
Development Master Plan, which provided a vision of
how to integrate the offshore wind capacities expected
for 2020 and 2030 [EWEA, 2009]. This European
vision must be taken forward and implemented by the
European Commission and the European Network of
Transmission System Operators (ENTSO-E), together
with a new business model for investing in offshore
power grids and interconnectors, which should be rapidly
introduced based on a regulated rate of return for
new investments.
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