All the major communications service providers have committed to carbon neutrality by 2050, while many equipment vendors follow initiatives like the European Commission’s Code of Conduct for Broadband Communication Equipment and are actively developing products that drive down energy consumption.
One of the most significant areas of progress has been in broadband.
The role of broadband in a green tomorrow
In the early days, as broadband started to take off, the focus was mainly on connections and bandwidth. However, as the thirst for bandwidth became apparent, the industry quickly realized the need to keep energy consumption in check.
Since the early 2000s, thanks to successive technological advances, the demand for data has not led to a massive increase in carbon emissions. Emissions have decreased recently since operators began upgrading older copper and cable networks to deep fiber or complete fiber-to-the-home networks.
While speeds have increased by 64, broadband power consumption has declined 38% since 2007. That’s a 100X gain in efficiency for the home and access networks with the evolution from ADSL to XGS-PON.
We have now reached the point where ICT generally carries a seven-fold net positive effect on greenhouse gas (GHG) emissions.
Broadband significantly contributes to this net effect by enhancing wealth, enabling efficiency gains, and reducing transportation. In other words, for every new household connected to high-speed broadband, we actively decrease overall carbon emissions for our planet.
Here are just a few key areas where broadband assists in reducing carbon emissions:
· Transportation. eCommerce, eLearning, telemedicine, home working, and video conferencing all reduce the need for transportation. Smart cities and smart roads depend upon broadband connectivity to regulate traffic flow, which also contributes to lowering GHG emissions.
· Production. The last 30 years have seen many physical products digitized: movies and music, newspapers and books, and invoices and receipts. Digitization leads to significant savings in using plastics, minerals, paper, and other physical materials and, of course, the energy required in manufacturing. None of these savings could be made without broadband being available to consumers and businesses.
· Smart Grids. The intelligent grid minimizes electricity waste by providing accurate real-time insight into demand, regulating production and consumption, and encouraging more responsible usage. The smart grid depends on robust and reliable broadband connectivity across the electricity network.
· Internet of Things. Connecting anything to anybody enables automation and data sharing for better decision-making, reducing physical displacements, saving time, and creating efficiencies.
Making the shift to fiber
Decoupling increasing energy consumption from the traffic growth began with the shift from copper to fiber. While the first GPON required roughly the same power to operate as copper, such networks delivered a 12-fold increase in capacity. This meant broadband services could improve, and more businesses and households could be connected per access node, effectively driving down power consumption per connection.
Belgian service provider Proximus has stated that their massive fiber deployment in Belgium has resulted in a 75% energy saving.
Another wave of efficiency gains came with successive generations of PON that improved the bits delivered per watt consumed. A recent study by Nokia Bell Labs shows that an FTTH network with XGS-PON consumes twice as much energy but delivers a five-fold increase in bandwidth compared to GPON.
This is one of the drivers for the adoption of XGS-PON. In their Fiber and Copper Access Equipment Forecast, industry analysts Omdia expects that XGS-PON shipments will reach almost 1 million units this year, with a forecast of 2 million port units by 2027.
25G PON brings an even more significant efficiency gain, delivering times better energy efficiency per bit over GPON. As the most efficient broadband access technology today, 25G PON offers just 0.25 W per gigabit power consumption.
Contrast this with the fiber extension technology G.fast: G.fast can deliver similar broadband speeds as GPON but consumes 1.6X more energy in the end-to-end network. With reverse powering from the home, the power consumption of an FTTB network with G.fast is roughly equivalent to FTTH GPON.
The green future technology is indeed fiber.
With the shift to fiber and passive power splitting, fewer ports and active electronics are needed to serve end-users, requiring less power provisioning in the network. Due to its confinement of laser light emissions inside the cable and its glass purity, fiber has extremely low attenuation (0.2 dB/km).
Passive fiber networks deliver the lowest ecological footprint. Sure, Gigabit Ethernet, 10 Gigabit Ethernet, and other point-to-point fiber technologies are competitive in power per bit. Still, they need to reap the benefit of the same infrastructure-sharing efficiencies. This advantage justifies PON as the ideal technology to distribute mass-market enterprise services and robust fiber transport for various 4G/5G cell sites and residential broadband.
It's in the chips.
If you measure the carbon footprint of a broadband access node through its complete lifecycle—design, manufacture, distribution, use, and treatment of the end of life—energy consumption in use accounts for about 89% of the total carbon footprint. And it’s the chipsets in these nodes that are the primary drivers of energy consumption. So, another area of industry focus has been designing more power-efficient chipsets.
Investments in next-generation silicon can push down the power consumption per bit. The latest PON chipsets offer vendors several advantages, including building line cards for fiber and copper broadband with higher port density, higher throughput per watt, and integrated energy-saving features.
Equipment based on these next-generation chips uses 50% less power in fiber installations than previous generations. It is two years ahead of the Codes of Conduct for Broadband Communication Equipment targets, helping service providers meet their emissions goals. Semiconductors also offer advanced abilities, such as powering down unused optics and enhanced intelligent fan tray control algorithms that ultimately decrease energy consumption and cooling when necessary and unnecessary.
Secondary savings complement those direct energy savings. More power-efficient chipsets lead to smaller power-optimized access nodes, which occupy less space, use less power, and can be passively cooled (up to operating temperatures of 65°C). This also reduces the installed battery capacity, and the chipsets require less AC grid protection equipment when installed in street cabinets.
Fiber for the future
Full-fiber networks are vital to sustainability in the telecoms sector as the most future-proof and energy-efficient infrastructure. Fiber broadband will reach 1.1 billion households worldwide by 2027. That represents only about 45% of all families, but there’s still a long way to go to close the digital divide.
For the foreseeable future, fiber extension technologies like G.fast improved wireless access and 5G mobile broadband will ensure the digital divide not.
All these networks still need considerable energy to operate, so, as an industry, we must continue to be relentless in our efforts to drive down watts consumed per bit delivered.
Sustainability initiatives such as product-product design, hardware refurbishment, recyclable packaging, and power-saving innovations minimize the carbon footprint of broadband networks while allowing more people to benefit from the economic and environmental benefits of fiber broadband.
Filip De Greve is the product marketing director for Nokia's Fixed Networks division. In that role, he is focused on the go-to-market go-to-market for fixed-access broadband solutions. Filip has over 20 years of experience in the telecommunications industry. He previously held various roles on the ICT provider and supplier sides.