The energy islands are our common Mars mission

Thursday 25 Nov 21


Jacob Østergaard
Professor, Head of Division
DTU Wind
+45 45 25 35 01


Denmark’s energy islands are hugely ambitious projects. It will require development and research—so let’s start now.

Feature in Ingeniøren
By Jacob Østergaard, Professor and Head of Center, DTU Electrical Engineering, and Glenda Napier, CEO of Energy Cluster Denmark.

A historic event will take place in 2030 when Denmark completes the world’s first energy islands on Bornholm in the Baltic Sea and in the North Sea, 80 kilometres off Thorsminde. These green power stations will represent the start of a new era in energy production and will be a significant part of the green transition in Denmark and Europe.

Everything about the islands is already big: the total construction cost of DKK 210 billion for the two islands corresponds to five Great Belt bridges. That will provide 12 GW of green electricity, corresponding to the power consumption of 12 million households.

It’s not just the costs and energy production of the energy islands that are groundbreaking.So is the innovation. The decision to establish the world’s first energy islands is brave and visionary. If we succeed, it will make Denmark the absolute leader in use and development of renewable energy for many years to come, and can potentially become a new Danish green energy adventure of historic dimensions.

"It would be sensible to use the first energy island, Bornholm, as a test case for the new solutions"

But unleashing this potential requires innovation. Developing and designing an energy island is no trivial task. It has never been done before and demands that we think carefully about the right solutions.

Right now, there’s a need for research, development, and innovation in at least three key areas:

Firstly, we must ensure that the construction of the energy islands is robust. The islands must supply stable and reliable electricity to the electricity grid, but that is not enough. We need to develop solutions and advanced software models that secure the systems against extreme or rare events, including cyber attacks, which are occurring with increasing frequency. New approaches are needed to ensure that the energy islands’ complexity does not lead to design flaws or result in such wide safety margins that development and operation become far costlier than they need to be.

The second thing we need to focus on is financially attractive solutions. For example, we must already now consider how to develop new electrical components for the offshore wind turbines that will be installed on the energy islands. Unlike the current turbines, these will not be directly connected to our electricity grid and will therefore not have to meet the same strict requirements. This alone will result in savings of several billion kroner. In the same way, we must review the other elements on the energy islands, such as transformers, HVDC connections, and the possibility of power-to-x systems in order to be able to assess in each individual case how the solutions can be put together in the most sensible and financially attractive way.

Finally, we must make sure that the solutions we develop don’t just live up to today’s standards and technological possibilities. We must make sure that they are future-proof, so they can provide the right basis when we develop new knowledge and opportunities in the coming years, and so they can be expanded and connected with more islands in future. Power electronics, intelligent digital control, and the structure of the electricity market are undergoing rapid developments, and there’s no doubt that we will soon have new advanced solutions that meet the requirements of the energy islands in a far better way.

The energy islands have to be completed within this decade. So we need to get started.

In our view, it would be sensible to use the first energy island, Bornholm, as a test case for the new solutions.Bornholm is interesting because the island is already there and we can get started quickly. In addition, Bornholm has the huge advantage that it’s easy to reach, and has a good transport network and existing social structures that make it easy to work there. This will not be the case with the coming energy island in the North Sea, which will require helicopter transport, clearing of access permits, and harsh working conditions on days with severe weather.

On Bornholm, we have every opportunity to test different constellations and control methods in an environment that’s flexible and used to functioning as a living energy laboratory. Once the solutions have been developed on Bornholm, it will be possible to replicate them on the energy island in the North Sea and on other future energy islands in Denmark and abroad.

Everything is ready, so let’s get started! The first tests and set-ups can be carried out now to set the pace and level of innovation needed to get the energy islands up and running, so they can contribute to the urgent green transition.

News and filters

Get updated on news that match your filter.
30 MAY 2024