Offshore: Enregy for the globe

So far, primarily European countries have been expanding wind power at sea. Now Asia and North America are following suit, driven by mutually agreed climate targets

The story of offshore wind power began more than 30 years ago outside the village of Vindeby on the Danish island of Lolland. There, eleven turbines turned in the sea for the first time in 1991. Since then, the community of 2,000 inhabitants has been considered the birthplace of offshore wind energy. Today, the power of the plants at that time seems rather unimpressive: each wind turbine generated only 0.45 megawatts. Today’s turbines have 15 times that capacity, and future ones will have more than 30 times that.

Meanwhile, offshore wind power is considered a central pillar of sustainable energy supply. Since 2012, the global capacity has increased tenfold. Last year, marine wind turbines provided almost 50 gigawatts of installed capacity. This equates to around 30 nuclear power plants and would be sufficient by German standards to reliably supply 100 million households with electricity. Sounds a lot. But it is not. The International Renewable Energy Agency IRENA calculates that by 2050 the world’s offshore wind farms will have to generate 2,000 gigawatts of electricity to meet the climate targets agreed in the Paris Agreement. So in 20 years’ time, marine wind turbines will have to generate 40 times as much electricity as they do today. A change in thinking is already under way. “In recent years, there has been a growing understanding of the great contribution offshore wind can make in the fight against climate change,” explains Alastair Dutton, Chair of the Global Offshore Wind Task Force of the world association GWEC.

Offshore turbines have a decisive advantage. Due to the constant wind at sea, they generate twice as much electrical energy as onshore wind farms. The dimensions alone are proof of this. The rotor blade of an offshore turbine will reach a diameter of a quarter of a kilometre in the coming years. There is enough space at sea. In the long term, offshore wind power is therefore considered a particularly promising form of electricity generation.

“The rotor blade of an offshore turbine will reach a length of a quarter of a kilometre in the coming years.”

Things are movingoff the coasts

At the same time, operators are building their wind farms further and further away from the coasts because the wind blows even stronger there. This trend will be strengthened by a new type of turbine that no longer needs to be installed in the seabed but rests on anchored floats. This allows wind farms to also be built in areas where the water is too deep for conventional construction methods. Countries with steep coasts can thus also enter the offshore wind power industry.

Falling generation costs are providing an extra incentive for the construction of offshore wind farms. This is not only due to technical progress. Value chains are also becoming more efficient. Planning agencies, construction companies and wind farm operators represent an important pillar. In addition, there are shipyards that manufacture special ships for the construction and operation of wind farms. Brokers arrange the right vessel for use in the offshore wind business.

The industry is currently receiving the biggest push from Asia. China in particular is investing billions in offshore wind power. More than 30 new parks are planned. But Vietnam and Taiwan in particular also have ambitious goals. The GWEC believes that the coasts of Asia hold the world’s greatest potential for the expansion of wind power by 2050. But European coasts also continue to offer good conditions. Even in the USA, where there are currently hardly any offshore wind turbines, signicant investments are planned for the coming years. The GWEC also sees considerable potential in Australia and South America.

Until 2030, the European countries will still be ahead when it comes to offshore wind power. For a long time, Germany was considered a particularly promising nation. However, in recent years, new construction has stagnated. One reason is new laws that provide for auctions instead of fixed subsidies. Anyone who wants to build a wind farm must submit a bid. The contract is awarded to the bidder who requires the lowest subsidy


In the meantime, the German government has increased the expansion target from 15 to 20 gigawatts by 2030 and to 40 gigawatts by 2035. For 2045, as much as 70 gigawatts are now planned. Experts expect further momentum for offshore wind power. This includes the introduction of contracts for difference after winning bids. While they cap profits through higher electricity prices, they also limit the risk. This allows operators a more reliable calculation. Contracts for difference already exist in different variants in Denmark, Italy, France and the UK. In the UK, the offshore wind industry has developed extremely well in recent years. The government has also increased the expansion targets.

Ex-Prime Minister Boris Johnson announced that by 2030 every British household should receive all its electricity from an offshore platform. The British benefit from their 12,000 kilometres of coastline. Around the 200 nautical mile zone there are numerous areas suitable for the construction of wind farms. What is more, in many places the water is not very deep. The costs of the expansion are thus kept within reasonable limits.

Other important wind power nations in Europe are the Netherlands and Denmark. However, anyone building an offshore wind farm in the Netherlands will have to do without subsidies. A lease may even be required for the constructors. Denmark relies on contracts for difference and is pushing ahead with expansion in the North Sea and Baltic Sea. Among its European neighbours, France is a developing country in the offshore sector – despite its long coastline. However, the government has raised the expansion targets for offshore wind power. At the same time, the approval procedures have been simplified. All nations are putting a lot of effort into the development of technology for floating wind farms. So far, France has not yet produced any wind energy at sea. Only two wind farms are currently under construction. One reason for the slow pace is the fact that more than 70 per cent of the nation’s electricity is generated by nuclear power plants, which emit hardly any CO2 . For this reason, the need for action to meet the climate targets is lower than for other countries.

“The first wind farm off the coast of Australia is set to become the largest in the world and propel it to the top of the global offshore countries.”

China takes the top spot

Asia’s rise in the offshore wind power industry is being driven in particular by China’s efforts. Today, the country has taken the lead worldwide. In 2021 alone, the People’s Republic added 12.7 gigawatts of installed capacity. A gigantic number. In purely mathematical terms, this would allow more than twelve million households in Germany to be supplied with power. The trend in China continues to head upwards: 33 offshore wind farms with a combined capacity of eight gigawatts are under construction and will be connected to the grid in the next few years. But it is not clear how the offshore boom in China will continue. For in 2022, the massive subsidies from the central government will expire. The pace of expansion depends on whether the provincial governments support this type of generation and how the production price develops.

In addition to China, the island state of Taiwan is pushing ahead with the expansion of offshore wind power, although only two wind turbines are currently in operation off its coast. However, a high population density and mountain ranges with peaks as high as 4,000 metres hardly offer any space for onshore wind turbines. Since the government declared in 2017 that it would phase out nuclear energy by 2025, offshore wind energy has been at the centre of energy supply. The government in Taipei had initially planned to connect plants with a total capacity of 15.5 gigawatts by 2035, and increased these targets by another 50 per cent in 2021. This would allow Taiwan to overtake its neighbours Japan and South Korea, which have also set expansion targets of a similar scale.

An ambitious newcomer to offshore wind power is Vietnam. The country has had a wind farm at sea since 2015. A second project is currently under construction. More parks are currently being planned. GWEC expects the government to announce further expansion plans, adopt a new energy development plan and define the framework for auctions.

Latecomer North America

The USA is one of the latecomers. Although the Atlantic and Pacific coasts offer good conditions, only two smaller wind farms on the East Coast generate electricity. Under Donald Trump, the planned projects hardly progressed, but after the change of government, the wind has changed. By 2030, 30 gigawatts of offshore wind power are to be fed into the grids. One major project has passed the final approval hurdle, and other projects are in the planning stage. The Spanish energy company Iberdrola had announced in February that it wanted to invest ten billion euros in three wind farms off the coast of Massachusetts.

Australia is also ready for take-off. For a long time, the government did not care much about a turnaround in energy policy. After the bush fires caused by drought, a rethinking is taking place. The first wind farm off the coast of the continent is set to become the largest in the world and propel Australia to the top of the global offshore countries.

It remains to be seen how the war in Ukraine will affect offshore wind power. In March, European Commission President Ursula von der Leyen pushed for more independence from energy imports. The Europeans absolutely had to break their dependence on Russian gas. At least off the coasts of the continent, a stronger expansion of renewable energies is on the horizon.