The powering of the digital age
As our appetite for digital services accelerates, so too does a less visible challenge – how to power it all, writes Phil Wiltshire, Contracts Manager at Pensdown.
The digital revolution is already embedded in daily life. Every email sent, film streamed, payment processed and artificial intelligence (AI) query answered relies on infrastructure that most people never see. Behind it all sit vast data centres, filled with servers, networking hardware, cooling systems and layers of electrical resilience. They are now as fundamental to modern economies as roads, ports and power stations.
Data centres must operate continuously. They are designed for uptime measured in fractions of a second, not minutes. That requirement drives extraordinary demands for electricity, redundancy and efficiency. Delivering that power is not simply a matter of connecting to the grid. It involves a carefully designed electrical ecosystem built around reliability, scalability and sustainability.
Data centres house computing, networking and storage systems that process and move vast volumes of data. These servers consume significant electricity in their own right. Alongside them, cooling systems, monitoring platforms and support infrastructure also require comparable levels of power. Typically, IT hardware accounts for between 40% and 60% of a facility’s electricity use, while cooling systems can represent 30% to 40%. Every watt drawn from the grid must be distributed, stabilised and used efficiently.
Globally, electricity demand from data centres reached approximately 415 terawatt-hours (TWh) in 2024 – about 1.5% of total global consumption. By 2030, projections suggest this could rise to around 945TWh. In practical terms, data centres could soon consume as much electricity annually as an industrialised nation such as Japan.
AI is a major driver. AI-optimised servers are energy intensive and analysts forecast their electricity use could increase almost five-fold between 2025 and 2030, accounting for nearly half of all data centre power consumption by the end of the decade. The United States and China are expected to dominate this growth, with Europe also expanding, albeit more steadily.
Why resilience is non-negotiable
With demand rising at this scale, reliability becomes critical. Even a brief power interruption can result in significant financial loss, reputational damage and contractual penalties. For industries such as finance, healthcare, government and e-commerce, uptime is not optional – it has to be guaranteed.
To achieve this, electrical systems are engineered with multiple layers of redundancy. Facilities typically incorporate dual utility feeds, automatic transfer switches and parallel distribution paths. Uninterruptible power supply (UPS) systems provide immediate back-up during grid disturbances, while diesel or gas generators sustain operations during prolonged outages.
Redundancy extends throughout the internal distribution network. Intelligent power distribution units (PDUs) enable load monitoring and segmentation at rack level, allowing engineers to isolate faults and rebalance circuits without widespread disruption. In the UK, UPS systems accounted for over 42% of power infrastructure investment in 2025, reflecting the priority placed on continuity.
Modern facilities are therefore designed for phased expansion. Hyperscale operators often build in stages, adding capacity as demand increases. Electrical systems must allow additional modules to be integrated without shutting down existing operations. Robust switchgear, scalable UPS frames and flexible PDUs make this possible, ensuring new capacity can be introduced seamlessly. Planning for growth at the outset reduces costly retrofits later. It also enables operators to respond quickly as digital workloads evolve.
Data centre infrastructure must also anticipate future demand. Power density per rack continues to rise, particularly in high performance computing and AI environments, where loads can exceed 100kW per rack. Such density places enormous strain on distribution boards, busways and cooling systems.
Efficiency and sustainability
How efficiently power is used is equally important. Energy represents one of the largest operational costs for data centres, making efficiency both an economic and environmental priority. Performance is typically measured using power usage effectiveness (PUE), which compares total facility energy consumption with the energy used by computing equipment. Leading facilities achieve PUE ratings close to 1.1, meaning very little energy is wasted. However, many sites still operate above this level, leaving room for improvement.
Cooling remains the largest opportunity for optimisation. Traditional air based systems are energy intensive, particularly in warm climates or high density deployments. Techniques such as hot and cold aisle containment improve airflow management, while liquid cooling technologies – transferring heat directly from components to circulating fluids – significantly reduce energy demand in high performance environments.
Renewable energy procurement is also becoming central to strategy. Operators increasingly secure renewable power purchase agreements (PPAs) or invest in on-site generation such as solar arrays and battery storage. While fossil-fuel generators remain necessary for resilience, decarbonisation strategies are advancing, with early experimentation in green hydrogen, geothermal energy and even micro-reactor technologies.
Such electrical installations must also meet strict standards covering grounding, bonding, arc-flash mitigation and integration with fire suppression systems. Thorough commissioning and documentation are essential, not only for safety, but also for insurance and regulatory approval.
Cybersecurity
Furthermore, cybersecurity is now part of the electrical conversation. Intelligent PDUs, UPS monitoring platforms and building management systems are networked and remotely accessible. As power systems become more connected, they must also be protected against digital threats. Secure configuration and physical safeguards are therefore integral to electrical design.
We can see therefore that data centres are engines of economic activity. They support global commerce, communication and innovation. But their success depends entirely on unseen electrical systems designed for resilience, scalability and efficiency. And as digital services continue to expand, the challenge is not simply building more data centres – it is powering them responsibly, reliably and sustainably. The infrastructure behind the screen may be invisible, but its importance to the digital age could not be clearer.
