As the UK accelerates toward its net zero commitments, the role of digital infrastructure in the energy transition is under increasing scrutiny. Data centres are vital to economic growth and digital resilience, but they are also significant energy consumers. Much of the attention to date has focused on power sourcing, cooling systems, and improving energy intensity through renewable integration. Yet one overlooked area of energy use sits at the heart of data centre operations: network switching.
Switching – the process of directing data between servers, storage and compute nodes – has long been treated as an operational necessity. But with workloads growing in volume and complexity, switching has become an unrecognised driver of power consumption and waste heat. It makes up a significant percentage of any data centre’s energy demands. According to NVIDIA, switching in data centres handling dynamic AI workloads typically makes up 8% of energy consumption. And as the sector looks for new ways to reduce its energy footprint, switching is emerging as a critical, addressable challenge.
The case for examining switching energy
At the technical level, most data centres rely on electronic switches that convert data signals between optical and electrical formats to make routing decisions. These conversions happen constantly and at scale, consuming energy and generating heat that must then be offset by the cooling system.
While this may have been a negligible overhead ten years ago, today’s workloads create vast quantities of east-west traffic inside the data centre. This translates into thousands of switch events per second, particularly in high-density or graphics processing unit (GPU) -based deployments. The result is a non-trivial contribution to overall power draw, as well as an additional thermal load that pushes up cooling requirements.
Switching and sustainability reporting
This becomes more than a technical concern when viewed through the lens of sustainability reporting. As Scope 2 emissions and energy intensity per workload come under increasing investor and regulatory scrutiny, operators need visibility over every part of the energy stack. And as more of the sector moves towards 24/7 carbon-free energy models, unnecessary switching overhead becomes a drag on both efficiency and transparency.
Smarter approaches to switching offer a way forward, and crucially, one that doesn’t rely on offsetting or behavioural change. Instead, it involves a rethink of how data moves inside the building.
The rise of optical switching
One of the most promising innovations is optical switching, which eliminates the need for optoelectronic conversion altogether. Rather than using electricity to make routing decisions, optical switches maintain the signal entirely in the light domain. This removes a major energy sink, cuts latency, and significantly reduces the amount of heat generated.
Finchetto, a UK-based innovator, has developed a passive optical switch that can operate at the packet level and be deployed directly in the rack. The technology is designed to integrate with existing data centre topologies, meaning it can be trialled in specific high-load zones without requiring a full re-architecture.
The gains aren’t just at the switch, they ripple outward. If the switch generates less heat, the cooling system doesn’t have to work as hard, which brings down total energy use and operating costs.
Impacts on cooling and infrastructure design
This relationship with cooling is key. Cooling systems remain among the most energy intensive components of any data centre. Even small improvements in thermal output from networking can create opportunities to reallocate cooling capacity, increase rack density, or explore more efficient cooling techniques.
In new-build and retrofit projects, a reduction in heat from the switching layer may also make it easier to design viable heat reuse schemes, redirecting waste energy to neighbouring residential, agricultural or commercial buildings. This kind of community-integrated energy thinking is becoming more attractive to developers seeking local authority buy-in or looking to comply with emerging sustainability certifications.
A practical path to decarbonisation
Optical switching is unlikely to be the silver bullet that decarbonises data centres on its own. But it represents the kind of low-profile, high-impact innovation that can help reduce the sector’s energy baseline without radical operational change.
Importantly, solutions like Finchetto’s are built for compatibility. They can operate alongside existing equipment, within familiar protocols such as Ethernet, and fit standard rack formats. This allows operators to implement change incrementally, targeting the areas where switching inefficiencies are highest, such as AI or HPC clusters, and validating gains before broader adoption.
Article written by Darren Watkins, Chief Revenue Officer at VIRTUS Data Centres.
Darren Watkins
