Largest Offshore Wind Farm in Denmark Increases Resonance

In 2027, the hammer will beat again on the fossil fuel industry. Renewable power is the new rhythm, and the turning of blades on wind turbines will be the tune. In Denmark, where renewable energy is being drummed into the system, the industrial sound of coal, gas, and oil is quieting down and the boom of Thor – an offshore windfarm, 20km from the town of Thorsminde – is amplifying.

Conductors of the new composition are RWE. Headquartered in Essen, Germany, the company has a global footprint and employs around 19,000 people, all tasked with enhancing the volume for renewables as the company phases out coal by 2030 and hits net zero by 2040.

Part of the score is 50GW of planned green generation by 2030, to the tune of €50 billion investment. Clearly, RWE has ambitions beyond the simple, and is challenging itself to do more.

In the North Sea, Thor will become home to 72 Siemens Gamesa 14-236 DD next-gen turbines, capable of producing 1000MW – enough clean, green energy for one million Danish households. Wind and solar are growing in importance in Demark, and RWE hopes that through Thor it will be able to assist in the transition in a major way.

As the largest offshore wind farm in Denmark, Thor turbines will eventually sit ion water depth of around 27m and each turbine will create 15MW with its 236m diameter rotor. Blades will be 115m long, and utilise IntegralBlade® technology which allows for 30% better efficiency compared to previous models. 

In January 2023, RWE announced the partnership with Siemens Gamesa and confirmed that installation would happen from a base at the Port of Esbjerg. Both Siemens Gamesa and RWE have committed upskilling in the local area and 60 permanent jobs will be created at the Port of Thorsminde, supporting the wind farm for 30 years.

“With Thor,” said RWE Offshore Wind CEO, Sven Utermöhlen, “we will massively contribute towards Denmark’s ambitious climate targets. In order to deploy this offshore project, we will rely on our track record of more than 20 years in offshore wind and on experienced suppliers. Based on an extensive procurement process we selected the preferred suppliers and booked the necessary production slots for all main components. This is an important step towards implementing this large-scale project – especially against the backdrop of the current market situation.”

Viewing Denmark as an important country in the clean energy transition, Siemens Gamesa was delighted to be selected as part of the supply chain. “We’re thrilled to collaborate once more with RWE, and feel particularly encouraged by the signing of the Preferred Supplier Agreement for the Thor project,” said Marc Becker, CEO Siemens Gamesa Offshore. “Our partnership already encompasses 12 offshore wind projects in both operation and development, totalling over 5.1GW of capacity in several countries. Connecting in Denmark today is a testament to our commitment to the country, and to the benefits we all gain from the Østerild test centre. Governmental support in all aspects of the wind industry – from projects to support schemes to research and development centres like this one – is critical for our future success.”

As seen in various markets around the world, the local impact from large construction projects offshore is immense. Skills are built and lasting legacies are left through the value chain. In Denmark, where there is much room for expansion – especially in offshore wind – RWE has drilled down on local procurement. To date, many contracts have been awarded to local companies for product, services, and consultancy.

International expertise has been sourced where necessary and EEW SPC will manufacture 36 monopile foundations, Wood Thilsted designed the foundations and Jan De Nul will provide the vessel for installation work, expected next year. Fred.Olsen Windcarrier will provide the vessel for the turbine installation and Hellenic Cables will provide the cable package. Alongside Jan De Nul, 60km of export cables and 200km of inter-array cables will be placed. MT Højgaard Danmark will carry out construction and civil engineering work for onshore substation alongside Siemens Energy. HSM Offshore Energy is the EPCIC for the substation and will complete in 2026.

Partnering with the best has allowed RWE to innovate like never before, making Thor a jewel in the crown of the country’s renewable energy capacity. And its construction will also allow for new methods, not seen elsewhere. The towers will be made from green steel that uses 63% less CO₂ than traditional thanks to the use of green electricity in the furnaces at the steel mills.

“Offshore wind already has one of the lowest life-cycle carbon footprints of power generation technologies,” explains Utermöhlen. “However, tower production accounts for around one third of all wind turbine-related CO₂ emissions. So, using greener steel is a significant step towards producing even more sustainable wind power. At RWE we are fully committed to working towards circularity and net-zero emissions. We are already testing the world’s first recyclable wind turbine blades by Siemens Gamesa under real-life conditions. By piloting the GreenerTower at our Thor offshore wind farm, RWE is now once again taking the lead by helping to significantly reduce the carbon footprint of wind turbines.”

RWE has wind farms in the UK, USA, Germany and elsewhere, and solar parks in Canada and Australia, and calls on 125 years of history in power generation to engineer ideas that will help achieve climate neutrality by 2040.

In June 2023, the company announced that it would use world-first recyclable rotor blades from Siemens Gamesa on the Thor offshore wind farm. 40 of the 72 turbines will be equipped with the new blades that are fully recyclable thanks to a new resin with a new, special chemical structure allowing materials to be separated easier. Materials can remain whole and be utilised for fresh applications following wind farm decommissioning.

“At RWE we are fully committed to working towards circularity and net-zero emissions. We are already testing the world’s first recyclable wind turbine blades under real-life conditions at our German offshore wind farm Kaskasi and we have decided to install them at Sofia. By using these rotor blades at our Thor offshore wind farm, too, RWE continues lead the way towards a circular offshore sector,” said Utermöhlen. “And we are doing even more. We are the first developer in the world to pilot Siemens Gamesa’s CO₂-reduced steel towers, which significantly reduce the carbon footprint of wind turbines. This is the right direction for the future of our sector, which has sustainability at its core.”

With more than one million tonnes of turbine expected to be installed each year, this development gives a lot of steel a second life, saving it from rust, decay, and waste.

Onshore, away from the waves and winds, work on the impressive onshore substation – Volder Søndervang – is underway following a groundbreaking ceremony in May. In the Municipality of Lemvig, amongst a number of high-profile dignitaries, the sod was turned as excitement around Thor was ramped up further.

“We already work closely with the local community, politicians, fishermen and educational institutions,” said Pia Lanken, CEO of RWE Renewables Denmark. “It is crucial that we are in dialogue with these stakeholders because we want to contribute to local development. This is one of the reasons why we have committed to employing at least 30 vocational trainees for this major project.”

The onshore substation will connect to the Energinet grid and green power will flow across the region, mitigating carbon and advancing Denmark’s goals.

Erik Flyvholm, Mayor of Lemvig said: “This is perhaps one of the most important groundbreaking ceremonies in Lemvig in recent times. It is the beginning of a massive wind project and the beginning of an energy adventure in Northwestern Jutland to the benefit of the climate, the region, and the municipality. I wish for a fruitful partnership with RWE that will benefit both parties.”

RWE focuses on creating energy for a sustainable life. The strategy is ‘growing green’ by investing carefully but heavily in opportunity-filled projects around the world. And, from 2027, when Thor is fully operational, all the notes in the soundtrack will crack to the beat of a renewable orchestra.

“In order to deploy this offshore project, we will rely on our track record of more than 20 years in offshore wind and on experienced suppliers, like Siemens Gamesa, which are committed to working hand in hand with Danish supply chain companies and the local workforce. As RWE, we want to be one of the key drivers of offshore wind energy in Denmark,” concludes Utermöhlen.