The Data Centre Network’s Role in Energy Efficiency

In today’s data centres, energy efficiency has become both a responsibility and a competitive advantage. Operators have already made big strides in optimising how facilities are powered and cooled. 

But there’s a third pillar that’s often overlooked - one that’s now proving as critical as AI, analytics, and high-density workloads reshape infrastructure demands.

That pillar is the data centre network itself.

The hidden cost of switching

At the heart of the network lies the switch. These devices direct traffic between servers, storage arrays and compute resources, performing countless operations every second. Traditional switches, however, rely on optical-to-electrical signal conversions to route data. These conversions, while fast, burn energy and release heat, adding pressure to both power budgets and cooling systems.

In the past, this overhead was tolerable. But with newer workloads, particularly AI training and edge analytics, requiring vast volumes of data to move fast and often, the inefficiencies in the switching layer are becoming impossible to ignore.

When networking becomes a thermal issue

It’s not just the power draw of the switch that’s a concern, it’s the heat it throws off. Every watt consumed at the switch becomes heat that needs to be extracted from the environment. And in tightly packed racks already pushing thermal boundaries, inefficient switching can tip the balance, forcing operators to limit density, increase airflow, or reengineer cooling layouts.

This turns a networking issue into a mechanical one. The switch, in other words, is no longer just an IT component - it’s a source of system-wide strain.

A shift to all-optical switching

In response, a new wave of technologies is challenging the status quo. All-optical switching eliminates the need for energy-intensive conversions altogether, keeping data in its light-based form from ingress to egress.

One UK company leading the charge is Finchetto. It has developed a passive optical switching platform that enables packet-level routing without the typical power overhead. By avoiding electrical processing, it not only reduces energy use but also slashes heat generation.

Optical switching gives operators the ability to reclaim both power and thermal headroom. By keeping data in the optical layer, it not only improves efficiency but also streamlines cooling strategies and creates new flexibility in how data halls are designed - from rack layout to density planning.

Knock-on effects across the stack

The benefits of optical switching ripple through the facility. Less heat from switching means fewer hotspots, lower fan speeds, and better airflow management. That can allow for tighter rack densities or create headroom for future growth.

It also eases pressure on supporting electrical systems. With reduced draw on power distribution units (PDUs) and uninterruptible power supply (UPS) units, facilities can downsize backup infrastructure or avoid costly overprovisioning.

For sites exploring heat reuse strategies, whether through local heating networks or internal energy loops, cutting out waste heat at the source makes thermal integration simpler and more effective.

Designed for gradual adoption

Operators are right to be wary of introducing unfamiliar networking gear into live environments. That’s why many next-gen optical solutions are built for modular deployment. Finchetto’s system, for example, supports standard protocols and can be slotted into spine-leaf architectures without ripping and replacing legacy hardware.

This allows for a test-and-expand approach: start with one rack or row, measure the impact, then scale. It’s a pragmatic route that aligns with typical refresh cycles and retrofit timelines across the UK’s colocation and enterprise market.

Why it matters now

Three forces are converging to make switching efficiency a top priority:

• Workload evolution: AI, high performance computing (HPC), and real-time applications are pushing bandwidth and latency demands skyward.

• Sustainability pressures: With ESG commitments rising and energy costs volatile, every kilowatt saved makes a difference.

• Technology readiness: Optical switching has matured and it’s no longer confined to labs and telcos and it’s ready for production environments.

Thinking systemically

The days of treating the network as an isolated domain are over. From cooling dynamics to energy provisioning, decisions made in the switching layer now influence the entire facility. A holistic view is essential.

Forward-thinking operators are reframing their network fabric as both a performance driver and an energy asset. And in doing so, they’re uncovering new opportunities to reduce footprint, control costs, and hit sustainability targets.

A smarter path forward

Switching may not be the most visible part of the data centre, but its impact is growing. As optical technologies mature, the opportunity to boost efficiency without disrupting everything else becomes too valuable to ignore.

For UK operators navigating energy uncertainty, emissions targets, and ever-increasing data demands, rethinking the switch could be the smartest move they make.