It isn’t a simple “good or bad” debate. Today, composites are often the most sustainable option available — and if we push their sustainability even further, they’ll become the best choice in many more applications, reducing environmental impact across multiple industries. So let’s break down where composites already shine… and where there’s still work to do.

Why are composites so good for sustainability?

Composites boost sustainability because they deliver huge lifetime efficiency gains. By making vehicles, aircraft, and turbine blades lighter, they reduce energy consumption and emissions or boost efficiency from the very first day of use.

Composites play a key role in modern wind energy. They enable longer blades and higher energy output, increasing efficiency while delivering massive lifetime emissions savings.

A well-known study from the University of Tokyo illustrates this perfectly: when comparing a conventional steel passenger car with a CFRP-lightweighted version, the CFRP car achieved about a 36% weight reduction, translating into roughly a 15% decrease in total life-cycle energy consumption. Even with the higher embodied energy of CFRP, the use-phase savings more than compensated for it.

Composites also last longer than metals in many applications — no corrosion, far less fatigue — meaning fewer replacements and less waste. And they offer engineers enormous design freedom: fibers can be placed only where strength is needed, reducing weight and material use even further, something impossible with isotropic materials like steel or aluminum. In short, composites help industries run cleaner, lighter, and longer.

How can composites be more sustainable?

There are countless initiatives aimed at improving the sustainability of composites. Universities, manufacturers, public institutions, and end users all recognize the advantages composites offer—and how much further their adoption could grow if they became even more sustainable.

At Managing Composites, we’ve shared several of the projects we’ve participated in, each perfectly illustrating the many angles from which composite sustainability is being addressed. In the COMIC project, for example, we worked alongside other companies to innovate in the manufacturing process, while in the MC4 project the focus shifted toward enabling true circularity.

Let’s take a look at some of the approaches currently being explored to enhance the sustainability of composite materials.

Material innovations

Natural Fiber Composites (NFC)

Natural Fiber Composites (NFCs) have become one of the most promising pathways for improving the sustainability of composite materials. By replacing synthetic fibers such as carbon or glass with bio-based alternatives like flax, hemp, jute, bamboo, manufacturers can significantly reduce the environmental footprint of a component from the very beginning of its life cycle.

Natural fibers require less energy to produce, rely on renewable agricultural sources, and often come with the added benefit of carbon sequestration during plant growth. Compared with traditional fibers, they offer lower CO₂ emissions, reduced reliance on fossil resources, and improved end-of-life options — including biodegradability in some configurations.

Flax-fiber monocoque for the LIUX BIG showing how natural fibers can deliver lightweight, strong, and more sustainable composite structures for the automotive industry.

While NFCs cannot yet match the mechanical performance of high-grade carbon fiber, they continue to get closer thanks to ongoing research and development. At Managing Composites, for example, we supported LIUX in the design and manufacturing of the monocoque using flax fiber — a material that delivers excellent performance for the vast majority of production vehicles.

Bio Resins

Bio-resins are another key pillar of composite sustainability, offering a way to reduce the environmental impact of the matrix itself — the part of the composite traditionally most dependent on petrochemicals. These resins are partially or fully derived from renewable sources such as plant oils, lignin, sugars, or other biomass, lowering reliance on fossil feedstocks and reducing overall CO₂ emissions during production.

Performance-wise, bio-resins have advanced dramatically. While early generations struggled to match the mechanical and thermal properties of conventional epoxies or polyesters, today’s bio-based systems are increasingly competitive — especially in automotive, mobility, sports equipment, marine components, and consumer products, where peak aerospace-grade performance isn’t required.

Recyclable Resins

One of the biggest breakthroughs in composite sustainability is the development of recyclable resin systems. Traditional thermoset resins form irreversible chemical bonds during curing, which makes them extremely durable—but very difficult to recycle.

Through innovations such as dynamic covalent chemistry (vitrimer resins), these next-generation systems can be reheated, reprocessed, and even chemically broken down to recover both fibers and resin. Instead of ending up in landfills, components made with these resins can be dismantled, reshaped, repaired, or fully recycled, extending their useful life and drastically reducing waste.

That is exactly what we did in the MC4 project — breaking down the kayak we had built to reprocess the material and create new paddles.

Final review of the MC4 project with the European Commission at the Waste Lab Bizkaia.

Recycled Content

Recycled fibers come from different sources — cured scrap, dry fiber offcuts, or end-of-life components — and can be processed into chopped, milled, or even continuous forms depending on the recycling method. While mechanical recycling typically shortens the fibers, the resulting materials still offer excellent stiffness and strength for many applications in automotive, mobility, construction, sports equipment, and consumer goods.

The environmental benefits are substantial: recycled carbon fiber can reduce CO₂ emissions by up to 90% compared with virgin fiber production, and recycled glass fiber dramatically reduces landfill waste, which remains a major issue in large-scale industries like wind energy.

One of the key challenges in composite recycling: effectively separating fibers from the resin matrix so they can be recovered, reused, and reintroduced into new high-performance applications.

End-of-Life Solutions

EoL (End-of-Life) innovation plays a key role in improving composites sustainability, which is why numerous research projects are underway to find effective ways to manage composite parts once they reach the end of their service life.

Design for Disassembly

The most forward-thinking approach is designing composites so they can be more easily taken apart at the end of their life. This includes using reversible chemistries (such as vitrimers or recyclable resins), reducing co-curing between subcomponents, incorporating fasteners instead of bonds where possible, and creating modular architectures. If a part is designed with its “goodbye” in mind, recycling becomes far more feasible and economically attractive.

Mechanical Recycling

This is the most established approach: the composite is cut, shredded, or ground into smaller fragments, which are then used as reinforcement in new materials. Although the fibers lose length (and therefore mechanical performance), the recycled material is perfectly suitable for applications in construction materials, automotive parts, panels, and other non-structural components. Its main value is simple: it prevents landfill waste and gives composites a second life.

Chemical Recycling

Chemical recycling goes deeper by breaking down the resin matrix to recover clean fibers — carbon or glass — with far less damage compared to mechanical methods. Technologies such as solvolysis, supercritical fluids, and catalytic depolymerization allow the recovery of high-quality fibers that can re-enter the supply chain. While still energy-intensive and not yet fully scaled, chemical recycling holds enormous promise for achieving true circularity, especially in carbon fiber.

TL;DR

Composites are already strong sustainability enablers thanks to lightweighting, long service life, and efficient performance across automotive, aerospace, and wind energy. A 36% weight reduction in CFRP cars, for example, can deliver ~15% lower life-cycle energy use.

But there’s still room to improve. Real progress comes from four fronts:
• Material innovation — natural fibers, bio-resins, recyclable resins, and recycled fiber content.
• Smarter manufacturing — processes and chemistries that reduce energy use and increase circularity.
• End-of-life solutions — design for disassembly, mechanical recycling, and chemical recycling.

The post Sustainability in Composites appeared first on Managing Composites.

Siemens Gamesa celebrated the delivery of green energy from the world’s first turbine equipped with the company’s composite RecyclableBlades. The first commercial installation of recyclable wind turbine technology recently took place at RWE’s Kaskasi offshore wind power project in Germany, marking what is said to be a turning point in the long-term sustainability of offshore wind power.

“We’ve brought the Siemens Gamesa RecyclableBlade technology to market in only 10 months: from launch in September 2021 to installation at RWE’s Kaskasi project in July 2022. The RecyclableBlade technology was developed in Aalborg, Denmark, the blades were manufactured in Hull, U.K. and the nacelles were produced in and installed from Cuxhaven, Germany” Marc Becker, CEO of the Siemens Gamesa Offshore Business Unit, says. “This is impressive and underlines the pace at which we all need to move to provide enough generating capacity to combat the global climate emergency. This milestone marks a significant contribution to Siemens Gamesa’s target of having fully recyclable turbines by 2040. With RecyclableBlade available for our customers, we can create a virtuous circular economy.«

https://www.compositesworld.com/news/siemens-gamesa-recyclableblades-installed-at-rwe-offshore-wind-farm

Definitely a step in the right direction!

Swedish company Trelleborg has launched low-friction thermoplastic composite bearings!

Trelleborg Sealing Solutions launched its latest lightweight thermoplastic composite bearing, the HiMod Advanced Composite Bearing Plus, an enhanced dual-layer bearing with a low-friction modified polyetheretherketone (PEEK) layer that reduces friction and increases wear performance for use in bearing, wear ring and bushing applications.

Manufactured using Trelleborg’s patented automated fiber placement (AFP) technology, a thin low-friction liner is bonded to the inner diameters and can be added to the outer diameters of the bearing to create a high-quality solution for use in a wide range of industries. According to the company, HiMod Advanced Composite Bearing Plus will not seize or gall, unlike metal bearings, to reduce the likelihood of pump damage in chemical processing applications, has a low coefficient of friction and can withstand extreme temperature ranges.

The company says the bearings can operate from a low temperature of -156ºC to +274ºC and are capable of continuous service even when wet, with nearly zero water absorption. Unlike other non-metal bearings, Trelleborg’s solution reportedly doesn’t crack or swell in extreme conditions, making them reliable for a wide range of applications.

Interested to know more about this project? Check out this link:

https://www.compositesworld.com/news/trelleborg-launches-low-friction-thermoplastic-composite-bearing

Now, let’s talk about the usage of carbon fiber composites in the marine industry:

Carbon fiber composite hydrofoils to enable “world’s fastest” electric ferry!

The Candela P-12 Shuttle is a hydrofoiling electric ferry set to hit the waters of Stockholm, Sweden, next year. Marine technology company Candela claims the ferry will be the world’s fastest, longest-range and most energy-efficient electric ship yet. The Candela P-12 Shuttle is expected to reduce emissions and slash commuting times, and will shuttle up to 30 passengers at a time between the suburb of Ekerö and the city center. With a speed of up to 30 knots and a range of up to 50 nautical miles per charge, the shuttle is expected to travel faster — and more energy efficiently — than the diesel-powered bus and subway lines currently servicing the city.

Candela says the key to the boat’s high speed and long range will be the ferry’s three carbon fiber/epoxy composite wings that extend from under the hull. These active hydrofoils enable the ship to lift itself above the water, decreasing drag.

The P-12 Shuttle features carbon fiber/epoxy wings, hull, deck, inner structures, foil struts and rudder built via resin infusion. The foil system that actuates the foils and holds them in place is made from sheet metal. According to Mikael Mahlberg, communications and PR manager at Candela, the decision to use carbon fiber for most of the boat’s main components was lightness — the overall result is a roughly 30% lighter boat compared to a glass fiber version. “[This weight reduction] means we can fly longer and with heavier loads», Mahlberg says.

https://www.compositesworld.com/articles/carbon-fiber-composite-hydrofoils-to-enable-worlds-fastest-electric-ferry

Our last story covers the usage of composite materials in the eVTOL industry:

Horizon Aicraft completes the construction of composites intensive 50%-scale prototype eVTOL aircraft!

Horizon Aircraft Inc., an advanced aerospace engineering company, has announced that it has successfully completed the construction of its 50%-scale “Cavorite X5” electric vehicle takeoff and landing (eVTOL) prototype. Jason O’Neill, Horizon Aircraft chief operating officer (COO), told CW that the hybrid-electric aircraft could not have been built without its advanced composites team led by Kirk Creelman.

Horizon’s approach and technology enables the five-seat aircraft to fly 98% of its mission in a low-drag configuration like a traditional aircraft. Flying most of the time as a normal aircraft is also safer and should make the aircraft easier to certify than radical new eVTOL designs, the company believes. The full-scale aircraft will also be powered by a hybrid-electric system that can recharge the battery array in-flight while providing additional system redundancy. Comprehensive testing of this 50%-scale aircraft will reduce technical risk moving forward as Horizon continues development of its full-scale aircraft.

“With a 22-foot wingspan, 15 feet in length and capable of speeds over 250 kilometers per hour, this 50%-scale prototype is an impressive aircraft,” Brandon Robinson, CEO of Horizon Aircraft, says. “Furthermore, it will yield valuable information that will help to reduce technical risk as we move forward with detailed design of our full-scale aircraft.”

https://www.compositesworld.com/news/horizon-aircraft-completes-construction-of-composites-intensive-50-scale-prototype-evtol-aircraft

The post August’s Top Composite News! appeared first on Managing Composites.