North Sea’s blueprint for the energy transition

Each hour in Kassø, near the Danish-German border, the renewable energy developer European Energy will produce one ton of carbon-free hydrogen to decarbonize shipping routes. East across the sea, the blades of the Moray West wind power plant are set to revolve off the Scottish coast and connect via offshore AC substations to the shore, providing enough electricity to power the equivalent of 1.3 million homes. While the world's longest HVDC interconnector Viking Link, at 765km, will enable the exchange of power across borders, functioning as an electrical superhighway connecting the British and Danish power grids.

The North Sea, a challenging environment with towering waves and biting winds, is becoming a showcase for a diverse mix of green technology in renewable power generation, infrastructure and Power-to-X. And if the energy transition can be delivered here, it shows that it can be achieved anywhere in the world. 

Brazil, for example, could connect gigawatts of untapped offshore wind potential along the Atlantic to the grid. The High Plains in Texas alone could supply enough wind energy to power 9 million homes in the US. And China’s western deserts, rich in wind and sun, could help the country stop adding new greenhouse gas emissions by 2030, despite an increase in energy consumption. 

The next five years are critical for climate action. Greenhouse gas emissions must be cut by 43 percent by 2030 (compared to 2019 levels) to limit global warming to 1.5°C, according to the IPCC. In response, 118 governments at COP28 pledged to triple the world’s renewable energy capacity by that time, and major industries have pledged to scale up zero-emission fuels derived from green hydrogen to 11 million tons.

Worldwide, the Global Wind Energy Council’s rolling ten year outlook details that, with the right regulatory framework, 410 gigawatts of offshore wind capacity can be deployed by 2033. But the rapid expansion of offshore wind “must be built on a growing collaboration between industry and government and the creation of streamlined and effective policy and regulatory frameworks”. And the energy transition isn't done with generation; as a second step, electricity and hydrogen need to be transported where they are needed. 

The projects in the North Sea are a prime example of how collaboration can help reach those goals. In 2022, the governments of Belgium, Denmark, Germany and the Netherlands signed the Esbjerg Declaration, initiating a cross-border collaboration to make the region “the green power plant of Europe”. Last year, joined by the leaders of France, Norway, and the United Kingdom and Luxembourg, they increased offshore wind targets from 30 gigawatts today to 120 gigawatts by 2030 and up to 300 gigawatts by 2050, covering more than half the renewable capacity required to make the EU climate neutral.

For the North Sea, several key factors make it a complete energy hub. Northwestern Europe, with its long coastline, ferocious storms and towering waves, can be a harsh environment, but “it's a great place for offshore wind,” says Lottie Edwards, Platform Package Manager at Siemens Energy. “It’s one of the windiest places on the planet.” Shallow waters make it easy to install turbines, plus the geology that kept natural gas in place for millions of years is the perfect place to bury carbon dioxide.

Edwards is responsible for installing and commissioning the transmission equipment for the Moray West project, an 882-megawatt wind power plant 22.5 kilometers from Scotland’s coastline. “When completed, the project will offset 1.1 million tons of CO₂ emissions each year,” says Edwards, “and provide enough renewable electricity for the equivalent of 1.3 million homes.” Siemens Energy is providing the offshore substation consisting of Offshore Transformer Modules (OTMs) for the project and the onshore substation, while partner Siemens Gamesa is responsible for the wind turbines and blades.

Viking Link is another project that illustrates how cross-border collaboration is key to building green energy hubs: A 765-kilometer HDVC interconnector linking Denmark and the UK. This bi-directional superhighway allows electricity to be transmitted between the two countries in both directions.

Such interconnectors help optimize the use of excess renewable energy, says Peter Weinreich-Jensen, Managing Director at Siemens Energy in Denmark. “We can send wind power to Denmark. Then after a few hours, when the winds blow in Denmark, we can send power back to the UK, exploiting excess energy and stabilizing the grid.”

Interconnectors act as a step path, allowing countries to connect with their neighbors to send surplus energy across borders, to where it's needed and vice versa. For example, the Danish power grid is also connected to the German one, adds Weinreich-Jensen, and allows electricity to be traded across Europe, positively impacting the continent’s green energy transition and increasing its energy security. 

The North Sea offers yet another way to use renewable energy with the production and storage of green hydrogen through electrolysis. In Kassø, Denmark, the world's largest e-Methanol production plant is being built, which will produce 42,000 tons of e-Methanol annually, synthesized from hydrogen and captured CO₂. “The electricity for the 50-megawatt electrolyzer plant will come from a local solar park and wind power from the sea,” says Holger Riess, Project Manager for Siemens Energy in Kassø. The project uses Siemens Energy electrolyzer technology to produce hydrogen. This is fed into a synthesis process where it is combined with carbon dioxide to produce e-Methanol.

Most of the e-Methanol will be supplied to the Danish shipping group, Maersk, to power their container ships. The green fuel is seen as crucial to the energy transition in shipping, which accounts for 3 percent of global greenhouse gas emissions. “There are about 55,000 ships in the maritime sector that run on fossil fuels, and e-Methanol is seen as one of the most important solutions to make these ships carbon neutral,” Riess says.

Hydrogen is not only in demand for shipping, but will also be used to reduce emissions from steel mills, refineries and the chemical industry. However, this will require millions of tons of green fuels. For the green transition, the world will need many energy hubs like the North Sea – with large-scale production of energy from renewable sources, interconnected grids and powerful plants to produce clean fuels. 

To reach net zero emissions by mid-century, reports the International Energy Agency in their Net Zero by 2050, “annual clean energy investment worldwide will need to more than triple by 2030 to around $4 trillion. This will create millions of new jobs, significantly lift global economic growth, and achieve universal access to electricity and clean cooking worldwide by the end of the decade.”

It is no surprise that creating a green energy hub in the North Sea is attracting global interest. Political stakeholders from countries as Australia, Japan and Vietnam have come to see what it takes to establish an integrated system that brings not only clean power, but also green jobs. “The countries surrounding the North Sea are in a great position to transition to a greener energy mix,” says Lottie Edwards.

Creating a standard for these new projects is important, says Edwards, adding that bringing in the experience from building similar facilities and using the standard designs developed in previous projects makes the process run smoothly and efficiently. Moreover, the experience can be applied to projects in other parts of the world: "If we can do it here,” says Edwards, “we can do it anywhere”.

About the author: Niels Anner is an independent journalist based in Copenhagen, who writes on business, science, technology and society in Northern Europe.

Combined picture and video credits: Siemens Energy