Offshore Electricity Infrastructure in Europe - European Wind Energy ...

use of the applied Weather Research and Forecasting
Model (WRF) [1]. WRF is a meso-scale numerical
weather prediction model, able to simulate the atmospheric
conditions across a wide range of horizontal
resolutions from 100 km down to 1 km. Once the WRF
model runs were performed and validated, the wind
speed time series at more than 350 offshore sites
and 16,000 onshore grid points were determined.
These wind speed time series were then converted
to wind farm power generation, based on wind farm
power curves. Power curves show the relationship between
how much power will be produced from the wind
farm under certain wind conditions. The resulting wind
power time series are used as input to the power market
and flow model described below.
3.2 Power market and power
flow model
Power plants generate when they can sell their electricity
to the market if there is enough grid capacity to
transport it. The power market and power flow model
[29] simulates the operation of the power system
based on a detailed set of European generation data
(capacity, costs, etc.) and a detailed European grid
model. Both conventional power plants and renewable
generation are modelled.
The tool used to perform the modelling is called the
Power System Simulation Tool (PSST) [2]. PSST combines
a market model with a model of the European
electricity grid, and assumes a perfect market with
nodal pricing. The socio-economic optimum for the
overall European electricity production is found by
minimising the total yearly generation cost. From
the simulations both technical and economic parameters,
such as generation cost, energy prices, price
differences and grid utilisation (off- and onshore) for
different scenarios can be extracted. The results from
this model together with the infrastructure cost model
(see 3.3) allow decisions to be made on whether a
specific offshore wind farm configuration is the most
beneficial.
OffshoreGrid – Final Report
3.3 Infrastructure cost model
Building offshore grid infrastructure requires large investments.
The extent of these investments is a key
factor to be taken into account when determining the
overall costs and benefits of the considered design.
The infrastructure costing model [26][27] is used to
determine the capital costing of the entire OffshoreGrid
infrastructure used in the modelling phases, including
individual wind farm connections, hub connections,
wind farm tee-in connections, direct interconnectors,
meshed hub-to-hub and hub-to-shore interconnectors,
and split wind farm connections. It takes into account
costs of different offshore cable and equipment technology,
the cable length, sea depth, bathymetric data,
project timing, onshore network security criteria, etc.
The infrastructure cost model feeds directly into the
net benefit model, together with the results from the
power market model to assess the viability of links
for arbitrage. The infrastructure cost model has two
main stages, firstly incorporating a technical assessment
of the required infrastructure to determine the
required technology and then a costing exercise is performed
to produce the capital costing for each wind
farm connection.
The costs produced by the infrastructure cost model
are determined mainly by what technology is required
and the connection distance. Following the calculation
of the route lengths a technical assessment is
made to determine the topology for each link. For wind
farm connections and hub connections this could be
either AC or DC depending on the distance. All interconnectors
for arbitrage have been assumed to be
HVDC due to the distances involved in connection. The
technology available is based on which technology is
commercially available today and future technology
established in Deliverable 5.1, available online [26].
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