Denmark is building an “energy island”
Thirty years after pioneering offshore wind, Denmark is set to expand the repertoire of renewables again, this time with the world’s first ‘energy island’. By 2030, an artificial landmass far from the country’s west coast will channel green electricity from a vast network of wind turbines and transmit it to the mainland – enough to power 3 million homes initially, then 10 millions.
As the window for preventing catastrophic climate change shrinks, large-scale projects of this type are essential to stem the rise in global temperatures. With a possible capacity of 10 gigawatts, the site will produce one and a half times the energy needs of the Danish population, leaving plenty for export to neighboring countries. “This is truly a great moment for Denmark and for the global green transition,” Energy Minister Dan Jørgensen said in a press release. “The island will make a great contribution to realizing the enormous potential of European offshore wind.”
The project is just the latest step in Denmark’s efforts towards sustainability. Last year, the nation pledged to reduce greenhouse gas emissions by 70% 1990 levels and achieve carbon neutrality by 2050. By the end of 2020, it also completed oil and gas exploration in its North Sea territory. But with a $34 billion prize – the largest construction effort in Danish history – the island marks a major commitment to climate action.
Energy Island Visions
As inviting as it sounds, don’t come looking for timeshares, sunny sands and scuba diving. It’s basically just a hub, a centralized power plant, surrounded by hundreds of wind turbines. The electricity they produce will go to the island and then to the mainland, in a configuration that will make the distribution of energy over a large region more efficient. And wind turbines this far offshore can be much taller – 850 feet, or nearly three times the height of the Statue of Liberty.
The island will come into being about 50 miles off the Jutland Peninsula, but its precise location has yet to be determined. In November, Energinet – the Danish company that will build and operate the electrical transmission system linking the island to adjacent countries – began assessing a strip of the North Sea known as Dogger Bank, a vast sandbank that offers the combined advantage of shallow water depths and optimal wind conditions. The government plans to select a specific site by spring, and construction is scheduled for 2026, allowing time to study the project’s impact on the seabed and marine life.
The design is also still uncertain. It might take one of many forms: a caisson, or massive concrete caisson filled with rocks; a floating platform tied in place; or a pile of sand. Details aside, it will span 1.3 million square feet, the equivalent of 18 football fields. At such a scale, the island will be able to transport an abundance of electricity, and it will be able to house facilities to store the excess. Some of the spare electricity could even be used to convert seawater into hydrogen through electrolysis, creating a renewable fuel source for planes, ships and heavy industry.
Extend Grid
The North Sea island is actually just one part of the equation. Off the other coast of Denmark, in the Baltic Sea, a natural island called Bornholm will serve as the second hub, with a capacity of 2 gigawatts. Similar to its artificial counterpart, it will produce wind energy for the Danish people and foreign countries – in November Energinet signed cooperation agreements with transport operators in Belgium and Germany. Both are likely to draw energy from the islands, bringing the European super network closer to reality.
The innovators behind the energy islands hope their project is just the beginning. As offshore wind technology matures, it could unlock huge unrealized potential. It is estimated that Dogger Bank alone houses up to 110 gigawatts of wind capacity — more than 10 times the generation proposed by Denmark for the region. And if this experiment succeeds, the model it is testing in the North Sea and the Baltic Sea could soon be emulated by coastal nations around the world, wherever the wind blows.