The environmental cost of the digital world is real and growing fast. Data centers used about 460 terawatt-hours of electricity in 2022; this year the figure is heading toward 650 to more than 1,000 terawatt-hours, between the annual power use of Sweden and of Germany.

The sector already accounts for around one percent of global carbon emissions, and AI is pouring petrol on the fire: a dense AI facility can draw four or five times the power of a conventional one, and global demand looks set to double by 2030. Water, swallowed for cooling, is the next limit on the horizon. None of this disappears by talking about ‘the cloud as if it floated.'

So, the honest question isn't whether data centers have a footprint. Of course they do. It is whether we measure it properly and deal with the waste inside it, and we are doing neither well.

The number everyone still quotes is power usage effectiveness, or PUE, which compares the energy a building draws to the energy reaching its computers. It is useful, but it tells you about overhead and nothing about whether the work is useful or the power is clean. You can post a lovely PUE while your servers idle, or run an efficient building on the dirtiest power on the grid.

Better measures exist, and we simply don't use them – carbon usage effectiveness, which exposes that a megawatt-hour from a coal-heavy grid carries many times the carbon of one in hydro-rich Sweden; water usage effectiveness; energy reuse; and the embodied carbon baked into hardware before it ever switches on. The standards are already written. What is missing is the will to use them honestly.

Once you measure the right things, the places to act announce themselves. Take waste heat. A data center is really an exceptionally large electric heater that happens to compute on the side, and most of that heat is thrown into the air. Capture it and thermodynamics works in your favour. Waste heat from a data center at Gatwick is set to pipe around 46 gigawatt-hours of heating to homes in nearby Crawley.

Meanwhile, in Norway, one operator runs its excess heat through a lobster farm, then sends the cooled water back to chill its servers. The technology isn't the hard part. The will to design it in from day one is.

This is the part I see most clearly because what we build is the switchgear, the critical power systems, and the modular plant beneath data centers. The gains in this business don't come from the marketing department. They come from the physical layer: efficient power, intelligent cooling, recovered heat, and capacity placed where it does the most work for the least waste. Unglamorous, and exactly where the biggest savings hide.

Consequently, we see it as our responsibility to help bridge the gap between digital growth and sustainable infrastructure. Designing and delivering intelligent power systems that optimise efficiency, reduce waste and incorporate green energy means the next generation of data centers can meet booming demand without compromising on climate goals or grid reliability.

The physical bottleneck is the power train – the path electricity takes from the street to the server. Most people assume energy is lost at the server, but a significant amount is actually wasted before it ever reaches the hardware.

Smart switchgear acts as the building’s brain. It receives high-voltage power and breaks it into smaller circuits, while monitoring this flow in real-time and reducing energy typically lost as heat during distribution.

Meanwhile, traditional air-conditioning is inefficient, but modular solutions use precision cooling to remove heat exactly where it’s generated – and combining these two systems can reduce energy waste by up to 30 percent. This provides a practical bridge that allows us to maintain digital infrastructure without placing an impossible burden on the existing grid.

All said, there is no single fix that carries the day, heat reuse needs something nearby to heat. The heaviest AI training will stay centralised and power-hungry. Efficiency gains get eaten by rising demand. Every lever helps; none is a cure.

So the goal was never zero. At this scale, zero is a fantasy. The goal is far less waste, honestly measured: judge a facility on its carbon, water, heat reuse and useful work, not one flattering ratio; recover heat rather than reject it; build where the power is clean, not only where the land is cheap.

The digital economy will not miraculously consume less. The responsible ambition is for it to waste far less, and draw what it needs more cleanly. Consequently, the greenest watt is the one we never have to generate, because we had the sense not to waste it.