For the past two decades, power architecture has evolved incrementally around a familiar model: utility AC enters the facility, passes through switchgear, transformers, UPS systems, power distribution units, and rack power shelves, and is ultimately converted to low-voltage DC for CPUs, GPUs, memory, networking, and storage.

That model worked for conventional enterprise and cloud computing. It was good enough when racks consumed 10kW, 20kW, or even 50kW, but it becomes far more difficult as AI infrastructure pushes rack densities toward hundreds of kilowatts and, in some designs, beyond 1MW.