Offshore transmission for wind: comparing the economic benefits of different offshore network configurations

It has been argued that increasing transmission network
capacity is vital to ensuring the full utilisation of renewables in
Europe. The significant wind generation capacity proposed for the North
Sea combined with high penetrations of other intermittent renewables
across Europe has raised interest in different approaches to connecting
offshore wind that might increase also interconnectivity between regions
in a cost effective way. These analyses to assess a number of putative
North Sea networks confirm that greater interconnection capacity between
regions increases the utilisation of offshore wind energy, reducing
curtailed wind energy by up to 9TWh in 2030 based on 61GW of installed
capacity, and facilitating a reduction in annual generation costs of more
than €0.5bn. However, at 2013 fuel and carbon prices, such additional
network capacity allows cheaper high carbon generation to displace more
expensive lower carbon plant, increasing coal generation by as much as
24TWh and thereby increasing CO2 emissions. The results are sensitive to
the generation "merit order" and a sufficiently high price would yield up
to 28% decrease emissions depending on the network case. It is inferred
that carbon pricing may impact not only generation investment but also
the benefits associated with network development.