MEGAWIND, the innovative solution for the most used foundations in offshore wind energy

MEGAWIND will last 3 years and is funded by the Hazitek Programme of the Basque Government.

MEGAWIND will improve monopiles, the type of foundation with the greatest potential in the wind power market, by integrating them with the new generation of large offshore wind turbines (+15 MW).

The project has started in 2022 with a consortium composed of 9 Basque companies of reference in the offshore wind sector, coordinated by ERREKA.

MEGAWIND was born out of the need to improve monopiles, which is the most widely used type of foundation with the greatest market potential, in order to integrate them with the new generation of large offshore wind turbines (+15 MW). Therefore, the main objective of the project is to develop innovations in the design and manufacture of the monopile itself, the transition piece and the joint system between the two.

According to the latest WindEurope report, in order to achieve the decarbonisation targets, set out in the Paris Agreement, in Europe alone and in this decade, offshore wind will increase from 28 GW installed at the end of 2021 to 135 GW in 2030. This means a threefold increase in the current annual installation rate, from just over 3 GW to 10-11 GW. The wind turbines to be used in offshore wind farms, which are increasingly more powerful, are installed on different types of foundations, with monopiles being the most widely used, accounting for over 80%.

As the size of wind turbines increases, the weight on the foundation increases and, consequently, so does the size of the large parts that support them: the monopiles, the bases that are driven into the seabed, and the transition pieces, the elements that join the monopile and the wind turbine tower. All this implies a series of challenges in the design, manufacture and installation of these components and the joining systems, as well as in the treatments and coatings that are necessary for their correct operation in a marine environment.

In this context, MEGAWIND aims to improve existing monopiles for integration into the new generation of large offshore wind turbines by pooling the knowledge of the consortium partners to develop innovative designs and manufacturing processes for the monopile itself, the transition piece and the connection system between the two.

From the point of view of the manufacture of the monopile itself, the increase in the power of wind turbines to 15 MW means that these elements exceed 10 m in diameter and 100 m in length. Their manufacture by conventional welding methods requires heavy and large steel plates, and the supply of these plates and their joining is the bottleneck in the manufacture of large monopiles. HAIZEA WIND and IBERDROLA will address the adaptation and validation of a vacuum electron beam welding method, never before applied to this type of components. The feasibility of this method would significantly increase the production rate.

Associated with the increase in the size of the monopiles is the increase in the size of the transition pieces and connecting flanges. These flanges, which are currently manufactured in a single piece of forging, will exceed 10 m in diameter. NAVACEL will work on the design of large flanges in sectors, which will bring a new supplier to a market with high demand.

The bolted joints that ERREKA will develop for future monopiles suppose a challenge for their handling, assembly and tightening, so the company will investigate two ways in the project: (i) development of tools and procedures to facilitate the installation and tightening of large metric bolts and (ii) development of innovations in the bolts, such as the combination of materials, to provide the same mechanical properties, but reducing the metrics of the bolts. In turn, ERREKA will develop a virtual sensor system to use the load monitoring capabilities of the i-Bolt® bolts to characterise the structural health of the monopile, the transition piece and the tower.

Finally, GALVASALA, TTT GROUP and FEX will work on three lines to meet the challenge of component survival in the demanding offshore environment: coatings for galvanised parts, heat treatments and corrosion protection by laser deposition. Bolted joints will be the critical element to be studied, where new methods to prevent corrosion of the material will be investigated.

The MEGAWIND project will have a positive effect on the supply chain around the project partners, such as the increase in activity in the port of Bilbao, or on the suppliers of raw materials for the manufacture of components, or the application of coatings to the new components. In short, the project will contribute to the positioning of the Basque Country as a benchmark in the manufacture of large parts for offshore wind energy, applying innovative technologies to develop these components.

The MEGAWIND project had its launch meeting last Friday 23 September at the Tecnalia facilities, where all the members of the consortium met, and will last for 3 years.

Project funded by the Department of Economic Development, Sustainability and Environment of the Basque Government (HAZITEK 2022 Programme) and the European Regional Development Fund (ERDF 2021-2027).