The Wind That Came Back
How a gearbox company from the Basque Country became one of remanufacturing's most important industrial arguments
There are two factories in the north of Spain where gearboxes and main shafts from wind turbines across the world arrive broken, worn, or at the end of what their owners assumed was their useful life. Inside, technicians with decades of accumulated knowledge in materials, tolerances, and mechanical failure disassemble them piece by piece, inspect every component against specifications that have been refined over more than sixty years, and rebuild them to improve their original design. Then, they go back out into the wind.
This is not recycling. It is not repair in the colloquial sense of tightening what has loosened or replacing what has cracked. It is remanufacturing: the systematic restoration of a product to an upgraded design—a process we call refurbishment—which includes improvements learned through the experience of thousands of manufactured and maintained units, incorporating quality controls and engineering judgment that transform what appeared to be waste into a second life of full industrial value. By combining their expertise as a manufacturer with extensive operation and maintenance experience, Gamesa Gearbox applies a strict re-engineering approach to determine the root causes of failures and improve the expected behavior of the repaired units. It is one of the most resource-efficient operations in all of manufacturing, and it happens quietly, at an industrial scale, in a facility most people have never heard of.
The Scale of a Circular Infrastructure The facility belongs to Gamesa Gearbox, a standalone business unit within Siemens Gamesa, the Spanish-German wind energy group that is one of the largest manufacturers of wind turbines on the planet. Its headquarters sits in Zamudio, in the Parque Tecnológico of Biscay, the same technology corridor that gave birth to much of the Basque industrial renaissance of the past three decades. Five manufacturing sites across Spain, in Asteasu, Burgos, Lerma, Mungia, and Sigüeiro, form a vertically integrated production system that covers everything from casting to assembly, testing to repair, and refurbishment to aftermarket services.
This is not a small operation experimenting with circular ideas; it is a mature industrial infrastructure that has been practicing the core logic of the circular economy since before that phrase existed. Gamesa Gearbox traces its origins to Echesa, a gear manufacturer acquired by Gamesa in 2001, which itself is the product of decades of Basque industrial tradition in precision mechanics. When the wind energy sector scaled rapidly through the 2000s and 2010s, the question of what would happen to all those turbines at the end of their design life became increasingly urgent. The answer for Gamesa Gearbox was not to plan for disposal, but to design for recovery.
In 2010, the company decided to convert two centers at risk of closure in the region of Galicia into a single hub dedicated to refurbishment, from which this activity has grown. Today, the Mungia and Sigüeiro facilities are fully dedicated to the aftermarket, currently processing nearly 800 units per year.
Re-engineering, Innovation, and Service Gamesa Gearbox’s aftermarket operations do not merely patch up old machinery; they actively upgrade it. The company boasts a repair catalog of over 130 different products, largely encompassing other manufacturers’ designs. This multi-brand, multi-technology approach provides them with unique drive-train knowledge, allowing them to determine what truly works in the field. To combat local damages and reduce repair costs, they utilize advanced technologies such as a combination of shot peening and superfinishing (IGS) to upgrade gears. For older or life-extended turbines, they offer “Life-X” versions, upgraded models that come with a 5-year warranty.
The customer experience has also been modernized to reflect transparency and agility. Through a proprietary web tracking system, clients have access to the work-in-progress status of their repairs, including approximately 200 files of documentation per unit. Furthermore, to tackle the critical issue of turbine downtime, they have introduced services like Flextock®, designed to improve the Cost of Energy (COE) through inventory optimization, and an Exchange (Swap) system that provides immediate availability of a refurbished gearbox while the customer’s damaged unit is evaluated and repaired.
The Sustainability Argument: Moving Away from the Linear Economy At its core, this refurbishment model is a powerful engine for sustainability, perfectly aligning with leading circular economy principles in industrial manufacturing. Taking a step away from the traditional linear economy, where new resources are extracted, used once, and then discarded, remanufacturing embraces a cycle of reducing, reusing, and recycling.
By choosing to rebuild a product using a mix of reused, repaired, and new parts, the environmental savings are staggering. According to similar models in the bearing industry, remanufacturing a heavy industrial component can reduce the carbon footprint by up to 90% and consume up to 90% less energy compared to manufacturing a brand-new unit. Beyond the environmental benefits, it makes undisputable economic sense: it can reduce operational and maintenance costs by up to 75%, significantly shorten lead times, and mitigate unplanned machine downtime. This model proves that extending the service life of critical assets and maintaining the value of spare parts is not just an ecological necessity, but a highly competitive business strategy.
A Global Model for the Future The scale of this reality is becoming highly visible. In 2018, Eneco, owner of the Princess Amalia Wind Farm in the Netherlands, selected Siemens Gamesa to refurbish the gearboxes of offshore Vestas V80-2.0MW turbines, successfully returning fully restored gearboxes to the wind. With the global market for wind turbine gearbox repair and refurbishment valued at approximately 1.69 billion dollars in 2025 and continuing to grow, Gamesa Gearbox is acting as a central industrial pillar, not as a new entrant following a sustainability trend, but as a pioneer who built the capability before the market demanded it.
This is the industrial argument that Oscar Lopez will bring to Palermo on 9 October. Working at the intersection of engineering, quality systems, and sustainability within Siemens Gamesa, Lopez will speak at EuAReman 2026. His presence there is the result of a chain of industrial knowledge networks, tracing back to Ihobe, the Basque Environment Agency, which has mapped Gamesa Gearbox as a primary reference case for industrializing the most demanding forms of product recovery.
During the Business Models panel, the question will no longer be whether remanufacturing is desirable, but how it works commercially: How do you build a value chain around components not designed to be returned? How do you convince asset owners that a rebuilt component is not a risk, but an asset? Gamesa Gearbox has been answering these questions with contracts, not concepts, for over a decade.
The wind energy sector is accumulating end-of-life assets faster than any traditional infrastructure can handle. What happens to the first generation of utility-scale turbines is one of the defining industrial questions of the coming decade. The answer that Siemens Gamesa and Gamesa Gearbox are demonstrating, that a gearbox does not end, but returns—is not a niche solution; it is a scalable global model. The gearbox that arrives broken and leaves restored is, ultimately, an argument about what manufacturing can be. It is a rejection of linear extraction and disposal, pointing back to something older and more durable: the craft knowledge that a thing can be made again.
Oscar Lopez · HSE & Sustainability Manager · Siemens Gamesa / Gamesa Gearbox · Business Models Session · EuAReman 2026, Day 3 — 9 October, Palermo
The full programme and registration: euareman.org