With modern data centres growing larger and more powerful, the need for improved energy efficiency and high-speed connectivity is pushing operators and engineers to look beyond copper wiring. Photonics technology, which promises energy savings and efficiency, is rapidly becoming a focus as facilities outgrow the limitations of traditional copper cables.
Scaling up: Decline of copper and emerging alternatives
As the industry’s appetite for scale intensifies, so does the push to replace copper cabling—long the backbone of data centre infrastructure. Chris Sharp, chief technology officer at Digital Reality, comments, “I think we’re at the end of copper,” clarifying that there’s no immediate shortage, but rather a technological turning point.
Despite this shift, copper remains core to data centre design. SP Global’s research shows that a single 100MW data centre incorporates roughly 400 tonnes of copper overall. Of this, up to 70 tonnes are found in the computing servers, while network cabling uses a maximum of 20 tonnes. Most of the copper supports electrical supply and facility cooling, but the internal data wiring is now at the forefront of efficiency initiatives.
Light-based networking opens doors for energy and speed
Photonics, which utilizes light (photons) instead of electrons to transfer data, was previously used mainly for long-distance transmission. Efforts by industry and academia are now directed at embedding these optical pathways inside data centres, linking hardware like GPUs and CPUs. According to Callum Littlejohns of Cornerstone Labs, photonics cuts heat output and energy usage for cooling and also enables multiple data streams to travel together through multiplexed optical channels, thereby expanding bandwidth.
However, implementing photonic interconnects brings challenges, especially when integrating optics with electronic circuits, sometimes even on the same chip. Peter O’Brien from Ireland’s Tyndall Research Institute suggests the sector is entering a new era of adoption after significant development periods, with support from industry leaders such as Nvidia driving momentum.
Obstacles for production and operations
Moving to photonics means aligning incompatible manufacturing pipelines and requiring both optical and electronic expertise. Andrew Wheeler of Hewlett Packard Labs notes that production remains expensive and geographically fragmented, with most assembly in Taiwan’s packaging facilities.
Operationally, heat management is a continuing concern, since although optical devices emit less heat than traditional counterparts, overall ambient temperatures in data centres remain high, posing risks for heat-sensitive photonics components. Rigorous cooling is required to keep systems stable, as Wheeler points out.
On the installation side, engineers need to learn new practices for deploying fibre networks. Unlike copper, fibre optics are vulnerable to damage from tight bends, meaning stricter installation protocols and specialized training, as explained by Sharp.
The path to fully optical data centres
Looking ahead, companies such as Resolight.ai are pioneering the concept of all-optical data centres. CEO Ofer Shapiro advocates for approaches in which data is processed and routed purely with light, eliminating repeated conversions from photons to electrons and back, thus maximizing efficiency and performance.
More immediately, the focus remains on expanding manufacturing and harnessing the sector’s existing electronics expertise to drive photonics costs lower. A notable advantage is that photonics parts are typically larger, so older chipmaking tools—like those used for Intel Pentium 4s—can be redeployed by firms such as Cornerstone. Littlejohns sees this recycling of legacy equipment as key to delivering photonics at scale and expects these advances to support many next-generation applications.
Ultimately, while not every technical or energy challenge in data centres can be solved through photonics alone, this emerging technology is positioned to transform IT infrastructure toward greater sustainability and scalability. As wider adoption takes hold, copper networks could soon be eclipsed by those built around light-based data transmission.