Data Centers Are Transitioning From AC to DC Power — Driven by AI Demands
The 800V DC Power Revolution in Data Centers
At last week's NVIDIA GTC conference, while new chip architectures dominated headlines, a quieter but equally significant shift was underway: data centers are moving from AC to DC power distribution. Announcements from Delta, Vertiv, and Eaton showcased new power designs purpose-built for the AI era.
The Problem: AC Conversion Waste
Today's data centers use AC utility power that undergoes multiple conversions before reaching compute chips:
- Medium-voltage AC (1kV–35kV) enters the facility
- Stepped down to low-voltage AC (480V/415V)
- Converted to DC inside UPS for battery storage
- Converted back to AC
- Converted again to low-voltage DC (~54V) at the server
Each conversion incurs power loss. Traditional racks draw ~10kW each. AI racks are approaching 1MW — at that scale, the copper, energy losses, and converter sizes become untenable. NVIDIA estimates a 1MW rack could require 200kg of copper busbar; a 1GW data center would need 200,000kg.
The Solution: Direct 800V DC
By converting grid power directly to 800V DC at the data center perimeter:
- 85% more power transmitted through the same conductor size
- Fewer fans, PSUs, and conversion steps
- Higher system reliability and lower heat dissipation
- Smaller equipment footprint
Industry Momentum
"While AC distribution remains deeply entrenched, advances in power electronics and the rising demands of AI infrastructure are accelerating interest in DC architectures," says Chris Thompson, VP at Vertiv.
The shift is being driven not by ideology, but by the sheer physics of delivering megawatts of power to AI compute racks efficiently.