Proposals for Europe’s offshore energy islands are gaining momentum, with regulatory issues rather than technology now looking like the largest barrier.

If massive offshore wind hubs are going to be built at scale, Europe will need to pull down the national borders that currently encircle planning and tendering for capacity, according to grid operator TenneT.

Mockups of the plans have been circulating for a few years. Initially they showed a huge cluster of offshore wind turbines centered around an island with energy storage and the transformer infrastructure required to send the power out across the "spokes" to countries across Europe.

This has now evolved into a series of hubs dotted around the North Sea rather than just one hub.

Offshore wind cost reductions, the development of floating wind and government funding are making what once seemed like a fanciful concept seem more realistic.

A collaborative project on the continent has been doing predevelopment work for more than two years. The North Sea Wind Power Hub (NSWPH) is a joint effort between network operator TenneT (mainly active in Germany and the Netherlands), its Danish equivalent Energinet, the Port of Rotterdam and the Dutch/German gas grid operator Gasunie.

The group hopes to pair hydrogen production facilities with offshore wind. Doing so would cut curtailment and replace the need for transformer infrastructure, with the energy transported to shore as hydrogen instead of electricity.

While that coalition has been exploring the many remaining technical questions, the concept recently received a political boost. The Danish government passed an updated climate bill earlier this month, including a commitment (source in Danish) to continue work on at least one energy island, with a view to having at least 10 gigawatts of offshore wind supported by the island concept.

The Danish government has made just short of $10 million available for the design of the island and the energy storage technology it will house.

TenneT has said the international nature of the planning involved will require a step away from the current siloed national offshore tendering and planning.

“An international coordinated approach could connect and integrate large-scale offshore wind more effectively and with significantly lower costs compared to a continued individual national planning,” TenneT spokesperson Mathias Fischer told GTM.

“The relevant wind power capacities in question range from 70 to 150 gigawatts by the year 2040 and up to 180 gigawatts by 2045 in the North Sea," Fischer said.

"They are intended to be developed using a modular, gradual approach. Depending on the scope of the development, the NSWPH could lay the foundation for supplying hundreds of millions of Europeans with green energy."

Credit: NSWPH

A simpler but related concept is already operating at large scale and providing lessons for networks on collaboration.

The Kriegers Flak pilot in the Baltic Sea has connected two offshore wind farms, one principally sending power to Germany and one to Denmark. Now the gap between the two wind farms is bridged. That means both projects' connections to shore and the new bridge cable can be combined to act as an interconnector when wind speeds are low. 

A substantial report for the European Commission looking into hybrid offshore wind projects found they can offer 10 percent savings right off the bat — a glimpse of what energy islands could achieve. As it stands, however, there are regulatory hurdles in abundance.

Chief among them is that national regulators are used to only having to think about their own domestic market. Finding solutions that work in multiple markets will be complicated. Even the construction of standard interconnectors is a lengthy and arduous process.

Another proposed hybrid project would see Vattenfall’s Norfolk Vanguard, to be built off the coast of the U.K., link to the Dutch IJmuiden Ver cluster, effectively adding another connection between the U.K. and the Netherlands. 

10 GW baby steps

There's also Brexit to think about, of course. The 337-page report for the European Commission on hybrid projects includes 15 Brexit disclaimers when discussing the U.K.’s potential role in hybrid projects.

The NSWPH has stated publicly that it wants to engage with both the Norwegian and U.K. authorities to pull them into the development of the offshore hub. As well as offshore wind expertise and access to the North Sea, both can also use oil and gas know-how to store hydrogen in offshore reservoirs and retrofit gas pipelines to transport hydrogen instead.

A spokesperson for the U.K.'s Department of Business, Energy and Industrial Strategy said: “The government recognizes the benefits of hybrid projects, including joint interconnector and wind projects, which may develop into efficient and cost-effective solutions to help the U.K. decarbonize. We are continuing to engage with stakeholders and developers to understand the potential benefits of these projects.”
For TenneT, regulations don’t have to slow down the development of the first island. It considers the next “logical step” for larger-scale offshore wind development in Europe to be the creation of a series of 10-15 gigawatt hubs, the optimal size according to its work so far.

“It is possible to build a first hub-and-spoke project within the current regulatory framework and market design, i.e., current EU and national legislation, but significant changes are required in national practices, approaches, planning and policies in order to allow for integrated infrastructure projects such as the modular hub concept being part of the long-term energy transition,” said TenneT's Fischer.

It would appear that Brussels is thinking along the same lines. The EU’s Green Deal, a roadmap to net zero emissions by 2050, states that the essential ramp-up of offshore wind deployment will need “regional cooperation between member states.” 

As part of the first raft of policies to be drawn up to deliver the Green Deal is a new offshore wind plan due next year. That could hold more indications on the near-term prospects for energy islands.