Riblet4Wind · Project

Shark-Skin Coatings That Make Wind Turbines Up to 6% More Efficient

energyPilotedTRL 7

Imagine running your hand over a shark's skin — it has tiny ridges that let the shark glide through water with less drag. This project took that same idea, already proven on aircraft, and applied it to wind turbine blades. They developed a special paint with microscopic grooves (called riblets) that reduces air resistance, so the blades spin more efficiently. Wind tunnel tests showed up to 6% more energy from the same blades — and they actually mounted coated blades on a real turbine to prove it works in the field.

By the numbers

Up to 6%

Direct efficiency increase from riblet coating (wind tunnel tested)

More than 10%

Total benefit including indirect effects (lower cut-in speed, better stall behavior)

20%

Target LCoE reduction for onshore wind by 2028

50%

Target LCoE reduction for offshore wind by 2028

71%

Industry partners in consortium

Consortium partners across 5 countries

The business problem

What needed solving

Wind turbines lose significant energy to aerodynamic drag on their blades, and operators have limited options for improving output from existing installations. Building larger blades or taller towers is expensive and faces planning restrictions, while noise emissions constrain onshore expansion. A coating-based efficiency boost that works on both new and existing blades addresses all three problems at once.

The solution

What was built

The project delivered coated rotor blades with riblet surface structures, mounted and tested on a real wind turbine. They also produced a disposable slot die applicator for the coating process, and an optimised lacquer material designed for rotor blade conditions. In total, 12 deliverables were completed including 4 physical demonstrators.

Audience

Who needs this

Wind farm operators looking to boost output from existing turbinesTurbine OEMs seeking blade performance differentiationBlade maintenance and repair companies offering retrofit servicesOffshore wind developers targeting cost reductionIndustrial coatings manufacturers entering the renewables market

Business applications

Who can put this to work

Wind Energy Generation

enterprise

Target: Wind farm operators and owners

If you are a wind farm operator dealing with underperforming turbines or rising maintenance costs — this project developed a riblet coating that can be applied to existing rotor blades to boost efficiency by up to 6%. The coating also enables turbines to cut in at lower wind speeds and operate better in gusty conditions, meaning more hours of generation per year. The technology works as a retrofit, so you don't need new turbines to see benefits.

Wind Turbine Manufacturing

enterprise

Target: Turbine OEMs and blade manufacturers

If you are a turbine or blade manufacturer looking to differentiate your product — this project demonstrated coated rotor blades with a riblet surface structure that improves the drag-to-lift ratio significantly. With up to 6% direct efficiency gains and indirect effects pushing above 10%, you could offer smaller, lighter blades that produce the same output. The consortium also developed a disposable slot die applicator for industrial-scale coating.

Industrial Coatings & Surface Technology

mid-size

Target: Specialty coatings companies and surface treatment providers

If you are a coatings company looking to enter the renewable energy market — this project created an optimised lacquer material and semi-automated application process specifically for riblet structures on large surfaces. The technology was originally proven in aeronautics and is now validated for wind turbine blades. With 7 consortium partners across 5 countries, the supply chain for materials and application equipment is already mapped out.

Frequently asked

Quick answers

How much efficiency improvement can we actually expect?

Wind tunnel experiments proved up to 6% direct efficiency increase from the riblet coating. When indirect effects are included — such as earlier cut-in at lower wind speeds, better stall behavior, and operation in sub-optimal wind conditions — the total benefit is expected to exceed 10%.

Can this be applied to our existing wind turbines, or only new ones?

The project explicitly addresses retrofitting. The riblet-paint technology can be applied on existing rotor blades, meaning you don't need to purchase new turbines. The consortium developed both the coating material and an applicator tool (disposable slot die) designed for field application.

Has this actually been tested on a real turbine, not just in a lab?

Yes. The project delivered coated rotor blades that were mounted on a selected wind turbine for field demonstration. This goes beyond laboratory testing — the consortium produced prototypes, designed the coating process, and validated it on operational equipment.

Who owns the intellectual property, and can we license this technology?

The project was coordinated by Fraunhofer, Germany's largest applied research organization, with 5 industrial partners in the 7-member consortium. Based on available project data, IP arrangements would need to be discussed with Fraunhofer and the relevant consortium partners. The technology originated in aeronautics, suggesting existing patent portfolios may apply.

Does the coating also reduce turbine noise?

Yes. The project objective states that the riblet structure will result in a substantial reduction of noise emissions. This is a significant secondary benefit, especially for onshore wind farms facing community noise restrictions.

What about durability — how long does the coating last on a blade?

Based on available project data, specific durability timelines are not published in the objective or deliverable descriptions. The consortium did develop an optimised coating material specifically for rotor blade conditions, suggesting weathering and wear were design considerations. Direct testing data would need to be requested from the consortium.

How does this affect the cost of wind energy?

The project aimed to contribute to the European Wind Energy Technology Platform targets: a 20% reduction of levelised cost of energy for onshore and 50% for offshore wind by 2028. The efficiency gains from riblet coatings — both direct and through enabling smaller blade designs — feed directly into lower cost per megawatt-hour.

Consortium

Who built it

This is a strongly industry-oriented consortium: 5 out of 7 partners (71%) are industrial, with Fraunhofer — Europe's largest applied research organization — leading the coordination from Germany. The consortium spans 5 countries (Austria, Germany, Denmark, Spain, UK), covering major European wind energy markets. With 2 SMEs in the mix alongside larger industrial players, the project bridges the gap between specialized coating know-how and large-scale wind energy deployment. Denmark's involvement is particularly notable given its position as a global wind energy leader. The single university partner suggests the science was already mature, and the focus was squarely on industrial demonstration.

BIONIC SURFACE TECHNOLOGIES GMBHparticipant · AT
UNIVERSITAT DE BARCELONAparticipant · ES

How to reach the team

Fraunhofer Gesellschaft (Germany) coordinated this project. SciTransfer can facilitate an introduction to the research team.

Order a report on this consortium

Next steps

Talk to the team behind this work.

Want to explore how riblet coatings could improve your turbine fleet's output? SciTransfer can connect you directly with the Fraunhofer team and consortium partners who built and tested this technology.

Order a report on this topic More in Energy & Climate