Windletter #130 - On blade manufacturing: the Vestas case
Also: the map with all wind turbines in Denmark, Spain has a problem with onshore wind permitting, Suzlon wants to return to Europe, and more.
Hello everyone and welcome to a new issue of Windletter. I'm Sergio Fernández Munguía (@Sergio_FerMun) and here we discuss the latest news in the wind power sector from a different perspective. If you're not subscribed to the newsletter, you can do so here.
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The most read pieces from the last edition were: the digital twins video, the installation of hub-mounted LiDAR, and Envision’s hire for European offshore.
Now, let’s get on with this week’s news.
🏭 On blade manufacturing: the Vestas case
Blades are probably one of the most critical and specialised components of the wind energy sector. They are the key component for capturing wind energy, but they also have a major impact on turbine cost and long-term reliability.
With the evolution of technology and the increase in wind turbine size, their manufacturing has become one of the main technical and industrial challenges for OEMs.
It is well known within the industry that the sector is carrying reliability issues linked to new platforms, both onshore and offshore. Manufacturing extra-long blades has proved to be a greater challenge than expected, with quality defects that are generating maintenance and reputational costs that may be higher than initially anticipated.
Blade manufacturing is labour-intensive and difficult to automate (although research is under way in this area). The process requires very large facilities, controlled environments, and operators specialised in composite materials.
This makes labour cost highly relevant when deciding where to locate a factory. It is estimated that the rotor (hub plus blades) typically represents 20–30% of the total cost of a wind turbine. Attention should also be paid to logistics, which play an important role both in cost and feasibility, as blades are the most complex component to transport.
A single large-blade factory can concentrate on the order of 500 to 2,000 direct jobs, in addition to all the indirect employment in logistics, tooling, maintenance, resins, fibres, etc. This also means that industrial policy places significant emphasis on blade manufacturing as one of the most attractive activities to attract and locate.
Manufacturing strategies of OEMs
Wind turbine manufacturers adopt different industrial strategies around blades:
In-house production: the OEM designs and manufactures the blades in its own plants, controlling engineering, processes, and quality throughout the entire supply chain.
Outsourcing / subcontracting: the OEM commissions the blades from an external manufacturer. There are two typical models:
Build-to-print: the supplier manufactures exactly the OEM’s design (the “same blade as yours”), following defined drawings, materials, and processes.
Design-to-specs: the OEM defines requirements and performance (loads, lifetime, interfaces, etc.), and the supplier proposes its own design to meet them (it does not have to be identical to the OEM’s).
As a result of outsourcing, large independent manufacturers have emerged, such as LM Wind Power (a subsidiary of GE Vernova), TPI Composites, Aeolon, or Sinoma, among others.
Almost all manufacturers combine both strategies and keep at least part of blade production in-house, although the percentage varies from one to another.
Of course, in recent years, as with other components, the Chinese supply chain has also gained prominence and is even expanding its manufacturing footprint beyond its borders.
Aeolon, for example, built a blade factory in Morocco in 2024 aimed at European projects. In addition, a large share of raw materials (resins, fibres, adhesives) originates in Asia.
The Vestas case
All of this can be connected to the Vestas case, which has recently been accelerating several strategic moves in its blade supply chain, strengthening its industrial capacity both in Europe and beyond, through a combination of in-house facilities and external partnerships.
Taranto (Italy) remains a key piece for European supply, both onshore (historically) and offshore (more recently). In fact, we recently reported how the factory had expanded its lines to serially produce the blades for the V236-15.0 MW. So much so that Vestas claims to have increased its workforce from 700 to 2,000 in just one year.
Vestas currently has in-house manufacturing of the V236 blades in Taranto and Nakskov (Denmark). The latter is Vestas’s historic blade plant, where a large part of its R&D is also concentrated.
However, according to what has been published, Vestas is also relying on the Chinese company Aeolon. I leave you here a video of the manufacturing of the V236 blade at Aeolon Nantong, Jiangsu.
The presence of a blade painted completely red indicates that it is a batch destined for Hollandse Kust West VI, in the Netherlands. It is worth remembering that Vestas has large volumes of orders for this turbine model, so it is possible that in-house manufacturing alone is not sufficient.
On the other hand, Vestas has recently completed the acquisition of the blade factory in Goleniów (Poland), previously operated by LM Wind Power. Curiously, this plant was already manufacturing blades for the V172-7.2 MW, but it will now do so under the Vestas umbrella. Along with the acquisition, Vestas kept the 400 workers and has recently announced that it will hire an additional 300 employees.
Nor can we forget the Spanish plant in Daimiel, in operation since 2008 and which began by manufacturing the now historic V90. Today, Daimiel remains focused on large onshore blades (V136, V150, V163).
Practically in parallel, there is news that Vestas would be negotiating the purchase of assets from TPI Composites. The transaction would include two TPI factories in India and Mexico, although there is still no official confirmation. In 2022, Vestas signed a multi-year agreement with TPI to manufacture blades for its 2–4 MW platforms and EnVentus.
It was also recently announced the definitive closure of the Tienli plant in Taiwan, with which Vestas had an agreement to manufacture in compliance with local content requirements. The government relaxed that requirement and everything suggests that this factory is no longer competitive.
All these moves seem to indicate that Vestas is reconfiguring its operations and securing a certain volume of manufacturing capacity under its own umbrella and without depending on third parties for the coming years.
🗺️ The map that shows all wind turbines in Denmark (and much more)
A few weeks ago, we commented in Windletter on the map that showed all wind turbines in Germany with an unusual level of detail. Now it is Denmark’s turn, with a map that also displays additional data that will delight the most hardcore enthusiasts.
The author of the map is DTU researcher Oliver Lylloff. Wind map 2.0 is an open tool that not only locates all wind turbines in the country, but also links them with meteorological and production data almost in real time.
What makes this map special?
Complete and official coverage: the wind turbine database comes from Energistyrelsen and was updated in November 2025. It can be filtered by manufacturer, size, location, and whether it is onshore or offshore.
Real wind: wind data is fed from DMI’s Harmonie forecast model, using open data.
Estimated production turbine by turbine: by combining wind data with generic power curves calculated in PyWake, the map estimates the instantaneous production of each wind turbine.
Real system production: when data is available, real aggregated generation figures are also shown, thanks to Energidataservice, with hourly updates.
Open Source: the entire project is open source, meaning it could be replicated in other countries.
You can access and play around with the map here. And I am still left wanting to have something similar for Spain. It is true that the data is not as transparent, but something could be done…
🌀 Spain has a problem with onshore wind permitting
Spain has a serious problem with onshore wind permitting. This is shown by the data published by Beatriz Mato on LinkedIn following the Bóreas report published by the AEE (Asociación Empresarial Eólica).
According to the report, since 2018 a total of 1,623 wind farms have been submitted to the administration, totalling 66,935 MW. There is one figure that sums it all up: only 9.37% has made it to construction.
Meanwhile, 23.11% has received a negative Environmental Impact Statement (DIA). And the rest is in the bureaucratic labyrinth of development. Sometimes waiting for the DIA, other times waiting for the Administrative Construction Authorisation (AAC)…
Even if the developer manages to reach the milestone of the Administrative Construction Authorisation (AAC), 18.4% of projects are conditioned or directly paralysed by administrative appeals (recursos de alzada), largely driven by anti-wind platforms.
To this group we can add the 7.3% with AAC paralysed by judicial decisions of the TSXG in Galicia, rulings that have been overturned by the Supreme Court and the CJEU, but which continue to generate an effective blockage.
There are also projects that have cleared the DIA, but where the conditions imposed have made the project economically unviable. For example, burying long lengths of high-voltage lines, with the cost that entails.
What is the consequence? Spain is barely able to build around 1 GW per year in a market that has a lot of interest and investor appetite for wind. Perhaps we could learn something from Germany.
*Note: The data represent wind farms built with public information since 01/01/2018 and not the total built since 2018. From 01/01/2018 to 31/12/2024, 8,620 MW have been built.
♻️ RenerCycle dismantles three wind farms in Navarra
Our sponsor RenerCycle has signed two contracts with Grupo Enhol for the dismantling and recycling of three wind farms in Navarra: Caparroso, San Gregorio, and Serralta. The contracts are part of the repowering process of the wind farms, which have been declared Projects of Foral Interest by the Government of Navarra. The first works have already started.
In total, RenerCycle will dismantle 87 wind turbines from the now-defunct manufacturer Ecotecnia (acquired by Alstom): 45 ECO44 (600 kW), 41 ECO48 (700 kW), and 1 ECO80 (1.6 MW). The scope includes full dismantling, logistics, comprehensive waste management, recycling and valorisation of components, as well as environmental restoration of the site under criteria of safety, traceability, and sustainability.
The repowering will drastically reduce the number of wind turbines. In Caparroso, the number will be reduced from 42 turbines to 6 new units. In Cabanillas, from 45 turbines to 5.
RenerCycle has already demonstrated that it is possible to reach 99.8% of refurbished components and recycled materials, as we previously reported in Windletter based on the experience of the Muel wind farm for RWE.
For those of you interested in learning in detail what is done with each component, I recommend that you read the feature report we published last October.
By the way, the dismantled wind turbines are already available in RenerCycle’s online shop. You can take a look here.
🎙️ The onshore perspective, WindEurope’s new podcast
There is always room for one more podcast in the market 🙂
That, at least, is what they must have thought at WindEurope, which has just launched The Onshore Perspective, a new podcast focused exclusively on European onshore wind.
Personally, I am glad to see that they are giving onshore wind its own space, an area that is often overshadowed by the shine of offshore, the pretty girl of the sector. But the reality is that the onshore sector remains the true industrial engine of the sector in Europe.
The first episode is already available and puts the spotlight on a particularly relevant case: the renaissance of onshore wind in Germany. A market that was practically blocked for years and that is now, by far, Europe’s onshore locomotive, as we discussed in Windletter a couple of weeks ago.
In this episode, host Giuseppe Costanzo speaks with Mirko Moser-Abt, Chief Policy Officer at Bundesverband WindEnergie (the German wind energy association), to analyse:
what has changed in the German regulatory framework,
which bottlenecks still exist,
and what the medium-term path may be to consolidate this recovery.
You can listen to the first episode on Spotify:
🌍 Suzlon wants to return to Europe and hires Paulo Soares to do so
The Indian manufacturer Suzlon Energy has announced its intention to strengthen its presence in Europe with the hiring of Paulo Soares.
Soares returns to the company, “like coming home” in his own words, to drive the manufacturer’s European strategy after having held senior roles at Suzlon between 2005 and 2010 (as CEO of the Chinese subsidiary) and between 2017 and 2020 (CEO of the international business).
His mandate now will be to develop access to the European market from Suzlon’s operating base in Aarhus (Denmark).
Soares arrives after almost two years as Managing Director Europe at SANY Europe, where he has managed to change, at least partially, the narrative around the arrival of Chinese OEMs in Europe, in a context of regulatory tensions.
Suzlon had a significant industrial presence in Europe from the early 2000s, and especially in 2007, when it acquired the German manufacturer REpower Systems (later renamed Senvion in 2014).
However, Senvion was sold in 2015, which effectively meant Suzlon’s exit from Europe, and the company attempted to refocus its business on high-growth markets. Later, in 2019, Siemens Gamesa ended up acquiring Senvion’s European assets, including the services business and a blade factory in Vagos (Portugal).
Since then, Suzlon has maintained a reduced commercial presence in Europe. According to its website, it maintains subsidiaries and offices in several countries in Europe, Africa, and LATAM (including Spain, Portugal, Romania, and Turkey), and with more than 1.5 GW installed in EMEA/LATAM.
In terms of products, the company has a portfolio of 2.X MW and 3.X MW turbines with low power density and lattice towers. Products that, a priori, do not fit in the European market, which in onshore is already moving towards much higher ratings, and which, if my memory does not fail me, has not installed a lattice tower in years. It will be interesting to see what strategy they follow.
Suzlon has a global installed base of around 15.4 GW in India, its local market, and close to 6 GW outside the country.
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Disclaimer: The opinions presented in Windletter are mine and do not necessarily reflect the views of my employer.