With access to power at a premium, data center power efficiency has come under the microscope. According to Gartner, more than 40 percent of existing AI data centers will face operational constraints within the next two years, putting profitability and competitiveness at risk as operators face the choice of limiting expansion or restricting workloads. The pressure is on to make every watt count.

While advanced AI accelerators use more power per chip than prior generations, they’ve also gotten better at using it, with significant gains in performance per watt for large-scale AI operations. Such hard-won efficiency gains need equal attention throughout the data center infrastructure. Keeping AI workloads humming requires reliable power availability all the way to the chip, which means that every pathway shuttling energy from the grid throughout the facility requires scrutiny, as does every system using it.

Is data center power architecture limiting compute capacity? Short answer: yes

When power availability lags compute capacity, servers sit idle — an expensive prospect in data halls flush with high-end GPUs and the potential, but not the ability, to process AI workloads. When it limits capacity altogether, competitiveness is at stake. Data center operators’ first concern is whether they can get access to power, and when. Right now, the average wait for grid connection in the US is one to three years, but it’s much longer in major data center hubs. In Europe, it’s even further out. The International Energy Agency (IEA) reports that 20 percent of data center build-out is at risk of delay due to grid congestion.

Let’s assume the data center gets connected to the grid. Data center operators must next deal with sourcing power infrastructure equipment. As the frenzy to stand up new data centers has eaten into inventory, lead times have extended from months to years for essential products. Higher demand-driven pricing has followed suit. The IEA report notes that prices for key grid components have nearly doubled over the past five years. Whether expanding an existing data center or kitting out a new one, AI workloads require the same gear. Access is king.

AI rack density is exceeding what traditional power architectures can accommodate

If data center operators didn’t have enough to contend with, the gap between traditional power architectures and AI rack density is widening. While 10-15 kW per rack is still common for enterprise workloads, density is circling 1MW per rack in AI factories. What was adequate a few years ago now must accommodate AI-dedicated facilities as well as hybrid environments running a mix of traditional and AI workloads. There is also compute capacity to wrestle with, which should not be confused with demand. Capacity is about potential. Demand is about immediate need. Anticipating tomorrow’s possibilities while delivering today’s requirements is a balancing act in and of itself. All of this comes into play as power infrastructure decisions are being made.

A KPI to meet the moment: Power availability per rack

Power availability per rack is becoming a defining key performance indicator (KPI) for data center operators, on par with power usage effectiveness (PUE). Power availability determines what type of equipment the rack can be outfitted with and by association, how much compute it can handle. A fixed cap is limited by the facility’s electrical and cooling capabilities. In contrast, power capacity per rack is an engineering limit defining the maximum power a rack’s electrical system can deliver.

A straight line can be drawn from power access and power infrastructure equipment to power availability per rack — you can’t use what you can’t get or distribute. Given the headwinds data center operators face in bringing on capacity, getting the most out of what they already have is essential.

Make the most of data center power with the right infrastructure efficiency stack

While power availability per rack is finite, that doesn’t mean it can’t change. Data center operators may amend their provisioning policies if they rebalance power distribution, add/remove IT equipment, address thermal overload, upgrade the electrical infrastructure, etc. Deploying an “efficiency stack” can produce tangible gains in power availability per rack. Here are a few tools data center operators have at their disposal:

  • Power conversion – Advances in DC power distribution, conversion topologies, and solid-state transformers can reduce energy loss, unlock stranded capacity, and deliver more usable power to IT loads.
  • Thermal system integration – Power architectures engineered to work with liquid cooling solutions from the outset can support higher rack densities, minimize heat-induced capacity throttling, and free up energy that would otherwise be expended on less efficient air-cooling systems.
  • Intelligent power management – Load prediction and dynamic power allocation can optimize real-time energy distribution, prevent unnecessary overprovisioning, and ensure that available capacity is allocated to the highest-priority workloads.
  • Modular solutions – Prefabricated power modules cut deployment time and reduce the tendency to overbuild in anticipation of future demand, enabling operators to incrementally scale power infrastructure while lessening the gap between installed and utilized capacity.
  • Power quality – Subharmonics, which can degrade power quality, can be addressed with technology that supports and balances power supplies during large power transients (voltage or current surges) caused by sudden changes in electrical loads, such as “spiky” AI training and inferencing.
Power lines
– Thinkstock / Yelantsevv

The importance of industry-wide collaboration

From grid to chip, power availability per rack is the bedrock of AI computing. It’s important for everyone in the industry to do their part to make energy reliable and cost-effective — and by “do their part,” we mean innovate and collaborate.

No single organization can solve power generation constraints, grid limitations, or rapidly evolving AI thermal loads. Companies across the ecosystem have a role to play, from the utilities delivering the energy to the suppliers and manufacturers providing IT hardware and infrastructure equipment to the operators making decisions that affect their bottom line and growth potential.

Collaboration produces measurable benefits, including; more compute per megawatt of energy consumed, shorter time to power for new AI capacity, better rack utilization when pockets of waste are eliminated, and improved return on capital investment.

Design for power availability from day one

Power availability per rack should not come as an afterthought, nor should standardization mean “set it and forget it.” Given the speed of innovation and the levers available to utilities, suppliers, manufacturers, and operators, a collaborative approach to power infrastructure, cooling systems, and IT equipment engineering can benefit everyone in the sector. Prioritizing scalable power electronics, integrated (or integration-ready) cooling systems, and AI-driven control systems is a good place to start. The companies that win the AI race will be those that make every watt count.