The voice of impact
ESG / CSR
Industries
MEASURE
ACT
COMFORM
Is fibre optic sustainable?
Level
The world runs on data. From streaming services to cloud computing and remote work, modern life depends on fast, reliable internet - and at the heart of it all is fibre optic technology. It’s faster, more efficient, and often hailed as the future of digital connectivity. But is fibre optic as sustainable as it seems?
On the surface, it looks like a clear winner over traditional copper cables. Fibre optics consume less energy, last longer, and can handle enormous amounts of data with minimal loss. Yet behind the promise of a greener, high-speed internet lies a more complex environmental story - one that starts with raw materials and ends with what happens when fibre optic cables reach the end of their life.
So, is fibre optic a genuinely sustainable solution, or are we overlooking its environmental footprint? Let’s take a closer look.
What is fibre optic technology?
Before diving into sustainability, it’s important to understand what fibre optic technology actually is and why it has become the dominant choice for high-speed internet and data transmission. Unlike traditional copper cables, which transmit data using electrical signals, fibre optics use pulses of light to carry information. This allows for significantly higher speeds, greater efficiency, and lower energy consumption over long distances.
How do fibre optic cables work?
“ Fibre optic cables are constructed from ultra-thin strands of glass or plastic fibres, which act as conduits for light signals. Each fibre is roughly the thickness of a human hair but can carry vast amounts of data at incredible speeds. The process relies on a principle called total internal reflection - when light is directed into the fibre, it bounces off the inner walls in a way that keeps it moving forward with minimal loss. ”
To prevent damage and interference, these fibres are bundled together and encased in multiple layers of protective materials, including plastic coatings, metal reinforcements, and insulation layers. The specific construction depends on the type of fibre optic cable and its intended use.
Types of fibre optic cables
There are two main types of fibre optic cables, each suited for different applications:
| Type | Description |
|---|---|
| Single-Mode Fibre (SMF) | Used for long-distance communication, such as undersea cables and national broadband networks. It has a narrow core that allows light to travel in a straight line, minimising signal loss over vast distances. |
| Multi-Mode Fibre (MMF) | Used for shorter-distance applications, like data centres and local networks. It has a wider core that allows multiple light signals to travel simultaneously, but with slightly higher signal loss compared to SMF. |
Because Single-Mode Fibre (SMF) is more efficient at long distances, it is typically used in large-scale internet infrastructure. Multi-Mode Fibre (MMF), on the other hand, is common in local area networks (LANs) and enterprise applications where extremely long distances aren’t required.
The advantages of fibre optic technology
Fibre optics have largely replaced copper cables in high-speed networks because of their many advantages:
| Advantage | Description |
|---|---|
| Faster speeds | Fibre optic cables can transmit data at speeds exceeding 100 terabits per second, making them the fastest communication medium available. |
| Lower energy consumption | Because fibre optics transmit data via light instead of electrical signals, they experience less resistance and require less power. |
| Greater durability | Fibre optics are resistant to electromagnetic interference, corrosion, and harsh environmental conditions, leading to a longer lifespan. |
| Higher bandwidth capacity | Fibre can carry vast amounts of data simultaneously, making it essential for streaming, cloud computing, and large-scale data centres. |
However, despite these advantages, fibre optic technology is not automatically a ‘green’ choice. Sustainability isn’t just about performance - it’s about the entire lifecycle of a product, from raw material extraction to disposal.
To assess whether fibre optics are truly sustainable, we need to ask some key questions:
- What materials go into making these cables?
- How energy-intensive is the manufacturing process?
- What happens when fibre optic networks need upgrading or replacement?
The answers aren’t as straightforward as they might seem, and that’s where the sustainability debate begins.
Close
The environmental impact of fibre optic production
“ Fibre optic cables are often seen as a modern, high-efficiency alternative to traditional copper wiring, but their sustainability isn’t as straightforward as it might seem. From the extraction of raw materials to the energy-intensive manufacturing process, fibre optic production has an environmental cost that’s often overlooked. While they may be more efficient in operation, the question remains - how sustainable is the process of making them? ”
Raw materials: what goes into fibre optic cables?
At the heart of fibre optic technology is silica, a material derived from quartz sand. Silica is one of the most abundant minerals on Earth, but turning it into the ultra-pure glass required for fibre optics is an energy-intensive process. The raw silica must undergo multiple purification steps before it can be drawn into the fine strands that make up fibre optic cables.
The production of optical fibre requires extreme heat - often exceeding 1,500°C - which translates into significant energy consumption and carbon emissions. High-temperature furnaces and chemical vapour deposition techniques are used to refine the glass, making this process heavily reliant on industrial energy sources.
But silica isn’t the only component of fibre optic cables. To ensure durability and performance, cables are coated with protective layers made from plastics and, in some cases, metal reinforcements. These include materials like:
| Material | Usage in Fibre Optic Cables | Environmental Concerns |
|---|---|---|
| Polyvinyl chloride (PVC) | Commonly used in the outer sheathing. | Relies on fossil fuels and is difficult to recycle. |
| Polyethylene (PE) | Often used as insulation. | Produced from fossil fuels, contributing to environmental impact. |
| Aramid yarn (e.g., Kevlar) | Used in some fibre optic cables to enhance strength and resistance to tension. | No standard recycling process, adding to disposal challenges. |
Different types of fibre optic cables require varying amounts of these materials. For example, Single-Mode Fibre (SMF) cables, commonly used for long-distance communications, have a thinner glass core but require precise manufacturing techniques to reduce signal loss. On the other hand, Multi-Mode Fibre (MMF) cables, which are often used in shorter-distance applications like data centres, tend to have thicker cores but require additional coatings and reinforcements to function optimally. The materials used in these different cable types influence their environmental footprint.
Manufacturing and energy use
Once the raw materials are refined, the actual manufacturing of fibre optic cables involves several energy-intensive steps:
| Process | Description |
|---|---|
| Purification of silica | Removing impurities to achieve the clarity needed for efficient light transmission. |
| Drawing the fibres | Heating the glass to extreme temperatures and pulling it into ultra-thin strands. |
| Coating and reinforcement | Applying layers of plastic and protective materials to improve durability and performance. |
| Cable assembly | Bundling individual fibres together into multi-strand cables for different applications. |
Each of these steps demands significant amounts of electricity and heat (often fuelled by fossil fuels), meaning fibre optic production has a substantial carbon footprint. While fibre optics are often seen as an improvement over copper in terms of energy efficiency, the emissions linked to their production remain a major concern.
Waste and offcuts
Not every metre of fibre optic cable that is produced actually gets used. The manufacturing process generates waste in the form of defective cables, offcuts, and excess materials. These discarded components contribute to the growing issue of electronic and industrial waste.
Unlike copper, which has a well-established recycling infrastructure due to its high resale value, fibre optic cables are far harder to repurpose or recycle. Their mixed-material construction makes separation difficult, and in most cases, disposal is the only option. This means that large amounts of unused or obsolete fibre optic material end up in landfills, adding to the industry’s environmental burden.
“ As the demand for high-speed internet continues to rise, the production of fibre optic cables is only going to increase. The challenge now is finding ways to make this process more sustainable - whether through greener manufacturing methods, improved recycling solutions, or reducing reliance on fossil-fuel-based plastics. Without addressing these issues, fibre optics may not be as sustainable as they first appear. ”
Energy efficiency and carbon footprint
“ When it comes to energy efficiency, fibre optic technology has a clear advantage over traditional copper cables. Fibre optics transmit data using light rather than electricity, which significantly reduces power consumption and improves efficiency. But does that mean they have a low carbon footprint? ”
Lower energy consumption in data transmission
One of the biggest environmental advantages of fibre optics is their ability to transfer data over long distances with minimal energy loss. Copper cables rely on electrical signals, which degrade over distance, requiring signal boosters and amplifiers that increase energy consumption. Fibre optics, on the other hand, transmit data as light, which encounters far less resistance, reducing the need for additional power.
Studies show that fibre optic networks consume up to 70% less energy per gigabit of data transmitted compared to traditional copper-based networks. This efficiency makes fibre optics a crucial technology for reducing the overall energy demand of global digital infrastructure.
Reduced cooling needs for data centres
Beyond transmission efficiency, fibre optics also contribute to reducing one of the biggest energy drains in IT infrastructure: cooling. Copper-based systems generate significant heat due to electrical resistance, which means data centres need extensive cooling systems to prevent overheating. Fibre optic cables, however, generate far less heat, significantly lowering cooling requirements.
Cooling accounts for nearly 40% of a data centre’s total energy use. By switching to fibre optic-based networks, data centres can significantly cut down on this energy demand. As global data demand continues to rise, switching to fibre optic networks could help data centres cut down on this massive energy expenditure.
A longer lifespan means fewer replacements
Sustainability isn’t just about energy efficiency - it’s also about durability. The longer a piece of infrastructure lasts, the fewer resources are needed to replace it. Fibre optic cables typically have a lifespan of 25 years or more, while copper cables degrade much faster and require more frequent replacement.
Fewer replacements mean lower demand for raw materials, less manufacturing energy use, and reduced waste. This longevity makes fibre optics a more sustainable choice compared to copper in the long run.
End-of-life and recycling challenges
Fibre optic technology may be efficient in operation, but what happens when these cables reach the end of their lifespan? Unlike copper, which has an established recycling market due to its high material value, fibre optic cables pose a far greater challenge when it comes to disposal and repurposing. With millions of kilometres of fibre being laid worldwide, the question of what happens to decommissioned cables is becoming increasingly relevant.
Why fibre optic cables are hard to recycle
The main issue with recycling fibre optic cables lies in their construction. Each cable consists of a delicate core made from ultra-pure silica glass, surrounded by layers of plastic coatings, protective sheathing, and sometimes metal reinforcements. Separating these materials is difficult and costly, making large-scale recycling impractical.
Unlike copper cables, where the metal can be easily recovered and sold at a profit, fibre optic components hold little resale value. The glass used in fibre optics is not the same as typical glass bottles or windows - it can’t be melted down and reused in the same way. And while the plastic coatings could technically be recycled, in most cases, they’re either incinerated or left to degrade in landfill.
The growing problem of fibre optic waste
As fibre optic networks expand, they are creating a new challenge: what happens to damaged, surplus, or decommissioned fibre optic cables? While fibre is still a relatively young technology compared to copper, early installations are already being replaced or upgraded in some regions, leading to a growing waste stream.
Most fibre optic waste currently ends up in landfills, as there are few viable options for recycling it. Although the cables themselves don’t contain hazardous materials like lead or mercury, their sheer volume is becoming an issue - especially as governments push for widespread fibre rollouts.
Additionally, when underwater or buried fibre optic cables are decommissioned, many are simply abandoned in place. The cost of retrieving and recycling them is often higher than leaving them where they are. This means miles of obsolete cables remain underwater or underground, contributing to environmental clutter.
Can fibre optic recycling become viable?
Recycling fibre optic cables is a tough challenge, but there are potential solutions. Some innovations that could make a difference include:
- Developing better separation technologies: If fibre optic materials could be efficiently broken down into reusable components, large-scale recycling might become more feasible.
- Designing cables for easier disassembly: Encouraging manufacturers to use materials that can be more easily separated and repurposed.
- Exploring alternative uses: Some research projects have looked at repurposing old fibre optics in construction materials or using silica for industrial applications.
For now, the lack of recycling options means fibre optics remain a product that is produced, used, and ultimately discarded. Until the industry finds a viable way to close this loop, the sustainability of fibre optics will always have this weak spot.
Fibre optic vs. wireless: Which is more sustainable?
Fibre optic networks aren’t the only option for high-speed internet - wireless technologies like 5G, satellite internet, and fixed wireless broadband are also shaping the future of connectivity. But when it comes to sustainability, which is the greener choice?
Energy consumption: Fibre vs. wireless
Both fibre optics and wireless networks require infrastructure, but the way they transmit data affects their energy consumption. Fibre optics use light signals that travel through cables with minimal resistance, making them highly energy-efficient. Wireless technologies, on the other hand, rely on radio signals that require energy-intensive transmission towers, data centres, and antennas to function.
Studies have found that wireless networks can consume up to 10 times more energy per gigabit of data transmitted compared to fibre optic networks. This is because:
- Fibre transmits data with minimal loss, reducing the need for repeaters or amplification over long distances.
- Wireless signals degrade over distance, requiring more base stations and power-hungry antennas to maintain connectivity.
- 5G networks rely on dense infrastructure, meaning they need more cell towers and small base stations to function effectively.
Infrastructure and material impact
“ Wireless networks may seem like a ‘cable-free’ alternative, but they come with their own environmental footprint. Building and maintaining 5G networks requires thousands of small cell towers, high-energy servers, and an extensive power supply. In contrast, fibre optic networks require upfront infrastructure investment but have a much longer lifespan and lower maintenance demands. ”
Another major difference is the materials used:
- Fibre optics rely on glass and plastics, but once installed, cables can last 25+ years.
- Wireless networks depend on high-tech components like rare earth metals, which have a high environmental extraction cost.
- Satellite internet systems require launching satellites into orbit, which has a massive carbon footprint and contributes to space debris.
Which option is more sustainable in the long run?
While wireless technology offers flexibility and convenience, it is significantly more energy-intensive to operate and maintain. Fibre optics, despite the environmental cost of production, are far more efficient in delivering data with minimal ongoing energy use.
That said, the future of connectivity will likely be a hybrid approach - using fibre as the backbone for high-speed internet while leveraging wireless technology where fibre installation isn’t feasible. The key to sustainability will be ensuring that both technologies evolve to minimise their environmental impact.
The role of fibre optic in a green digital transition
As industries and governments push for a greener, more energy-efficient future, fibre optic technology is playing a crucial role in reducing the environmental impact of digital infrastructure. By enabling faster, more reliable internet with lower energy consumption, fibre optics support a range of sustainability initiatives - from smart cities to remote work and cloud computing. But how exactly does fibre contribute to a greener digital world?
Smart cities and energy efficiency
“ Fibre optics are a key enabler of smart cities, which use digital technology to improve urban efficiency, reduce emissions, and enhance sustainability. High-speed fibre networks allow cities to integrate real-time data collection, optimising energy use in everything from transportation to public lighting. ”
For example:
- Traffic management systems can use fibre-enabled sensors to reduce congestion and cut transport emissions.
- Smart grids powered by fibre connectivity help balance electricity demand and integrate renewable energy more effectively.
- Energy-efficient buildings can use fibre-connected IoT (Internet of Things) devices to monitor and reduce energy waste.
By providing low-latency, high-bandwidth connectivity, fibre optics make these innovations possible, helping cities lower their overall carbon footprint.
Reducing the need for physical travel
One of the most immediate sustainability benefits of fibre optics is their role in reducing emissions from travel. With fast, stable internet, more businesses and employees can embrace remote work, cutting down on commuting-related emissions.
- A study by the International Energy Agency (IEA) found that if just 10% of the workforce worked remotely three days a week, global CO2 emissions from commuting could be reduced by 24 million tonnes annually.
- High-speed fibre connections enable video conferencing, online collaboration, and cloud-based work environments - reducing the need for business travel and office energy use.
Integration with renewable energy
“ The energy efficiency of fibre optic networks becomes even more impactful when combined with renewable energy sources. Data centres and digital infrastructure are among the largest consumers of electricity worldwide, but many companies are now committing to 100% renewable energy to power their fibre-based networks. ”
For example:
- Google and Microsoft have pledged to run their data centres entirely on renewable energy by 2030.
- Some telecom providers, such as BT Group in the UK, are rolling out fibre optic networks powered by wind and solar energy.
By reducing overall electricity demand and making it easier to integrate renewable energy into digital infrastructure, fibre optics support the transition to a lower-carbon internet.
“ While fibre optics have clear environmental benefits, challenges remain in making them fully sustainable. Issues around production emissions, material sourcing, and end-of-life disposal still need to be addressed. However, with continued investment in greener manufacturing practices and better recycling solutions, fibre optics have the potential to be a key driver of a more sustainable digital future. ”
Close
What about Greenly?
While fibre optics play a role in making digital infrastructure more energy-efficient, true sustainability requires a comprehensive approach, one that looks beyond individual technologies to the bigger picture of emissions management. That’s where Greenly comes in.
Our suite of carbon management services helps businesses understand, track, and reduce their environmental impact at every stage of their operations. Whether you're in the telecom sector, a tech company, or any other industry looking to improve sustainability, Greenly provides the tools and expertise to make it happen.
How can Greenly help?
- Comprehensive carbon tracking: We help businesses measure Scope 1, 2, and 3 emissions, providing a clear picture of where their carbon footprint lies.
- Lifecycle assessments: Understanding the full environmental impact of products, from production to disposal.
- Actionable decarbonisation strategies: Custom recommendations to reduce emissions in line with science-based targets.
- Supply chain emissions management: We provide insight into supplier emissions, helping businesses build more sustainable value chains.
- Regulatory compliance support: Ensuring companies meet evolving sustainability regulations, such as the Corporate Sustainability Reporting Directive (CSRD) and other international frameworks.
By providing data-driven insights and tailored strategies, Greenly empowers companies to reduce emissions, cut costs, and enhance their sustainability credentials.
Want to take the next step in sustainability? Get in touch with Greenly today.
Sources
- Greenly, What’s the Environmental Impact of Streaming?, https://greenly.earth/en-gb/blog/industries/whats-the-environmental-impact-of-streaming
- NAI Group, Optical Fiber Technology: How It Works, https://www.nai-group.com/optical-fiber-technology-how-it-works/#:~:text=Light%20travels%20down%20a%20fiber,cable%20and%20the%20glass%20structure
- Universal Networks, What is the Difference Between Multimode and Singlemode Fibre Optic Cable?, https://www.universalnetworks.co.uk/faq/what-is-the-difference-between-multimode-and-singlemode-fibre-optic-cable/#:~:text=There%20are%20two%20primary%20types,the%20middle)%20travels%20the%20slowest%20travels%20the%20slowest)
- Greenly, Everything You Need to Know About LCA (Life Cycle Analysis) in 2022, https://greenly.earth/en-gb/blog/company-guide/everything-you-need-to-know-about-lca-life-cycle-analysis-in-2022
- STL Tech, From Sand to Optical Fibre: The Story of Digital Connectivity, https://stl.tech/stl-stories/from-sand-to-optical-fibre-the-story-of-digital-connectivity/
- Yelco, Fiber Optic Cable Manufacturing Process: How They Are Made, https://blog.yelco.tech/fiber-optic-cable-manufacturing-process-how-they-are-made
- Greenly, Fossil Fuels: Pros, Cons, and Alternatives, https://greenly.earth/en-gb/blog/ecology-news/fossil-fuels-pros-cons-and-alternatives
- International Copper Association, Copper Recycling, https://internationalcopper.org/resource/copper-recycling/
- Greenly, Our Guide to Waste Management, https://greenly.earth/en-gb/blog/ecology-news/our-guide-to-waste-management
- Greenly, All You Need to Know About Energy Efficiency, https://greenly.earth/en-gb/blog/company-guide/all-you-need-to-know-about-energy-efficiency
- Weezie, Can FTTH Networks Have a Positive Impact on Sustainability?, https://weezie.io/2024/01/24/can-ftth-networks-have-a-positive-impact-on-sustainability/#:~:text=Reduced%20Energy%20Consumption,-FTTH%20networks%20are&text=In%20fact%2C%20fiber%20optic%20cables,70%25%20compared%20to%20cable%20networks
- Greenly, Do Green Data Centers Exist?, https://greenly.earth/en-gb/blog/industries/do-green-data-centers-exist
- BP, Castrol Liquid Cooling for Data Centres, https://www.bp.com/en/global/corporate/news-and-insights/energy-in-focus/castrol-liquid-cooling-for-data-centres.html
- Optinet, Lifespan of Fibre Optic Network Materials: Built to Last, https://optinet.co.uk/blog/lifespan-of-fibre-optic-network-materials-built-to-last/#:~:text=With%20proper%20installation%2C%20fibre%20optic,the%20longevity%20of%20fibre%20cabling
- Les Enovateurs, Network 5G: Ecological WiFi, https://les-enovateurs.com/network-5g-ecological-wifi
- Greenly, What Are Rare Earth Metals?, https://greenly.earth/en-gb/blog/industries/what-are-rare-earth-metals
- Greenly, Why is Space Junk a Problem Both for Exploration and the Earth?, https://greenly.earth/en-us/blog/industries/why-is-space-junk-a-problem-both-for-exploration-and-the-earth
- Greenly, What is Saudi Arabia’s Eco-Friendly City The Line?, https://greenly.earth/en-gb/blog/company-guide/what-is-saudi-arabias-eco-friendly-city-the-line
- Greenly, Smart Grid: All You Need to Know, https://greenly.earth/en-gb/blog/industries/smart-grid-all-you-need-to-know
- International Energy Agency, Working from Home Can Save Energy and Reduce Emissions – But How Much?, https://www.iea.org/commentaries/working-from-home-can-save-energy-and-reduce-emissions-but-how-much
- Greenly, Can Business Travel Become Sustainable?, https://greenly.earth/en-gb/blog/industries/can-business-travel-become-sustainable
- Greenly, What is Renewable Energy and Why is it Beneficial?, https://greenly.earth/en-gb/blog/company-guide/what-is-renewable-energy-and-why-is-it-beneficial
- Google, Operating Sustainably, https://datacenters.google/operating-sustainably/
- Microsoft, Powering Sustainable Transformation, https://datacenters.microsoft.com/globe/powering-sustainable-transformation/
- BT Group, BT Group Switches on First Self-Powered Mobile Site Energised by Solar and Wind, https://newsroom.bt.com/bt-group-switches-on-first-self-powered-mobile-site-energised-by-solar-and-wind/#:~:text=23rd%20October%202024%3A%20BT,solar%20panels%20and%20wind%20turbine