Alderbuck Energy to Deploy 800 VDC Solid-State Transformer at San Diego Supercomputer Center
- Architecture: 12 kV AC to 800 VDC
- Capital cost reduction (claimed): 20-30 percent
- Construction timeline reduction (claimed): 30-50 percent
- Efficiency gain (claimed): up to 4 percent
- Funder / site: California Energy Commission / San Diego Supercomputer Center
Alderbuck Energy will deploy its Nexus Power Unit, a medium-voltage solid-state transformer, at the San Diego Supercomputer Center at UC San Diego under a California Energy Commission-funded project to test high-voltage DC power for AI data centers, the company said June 23, 2026. The demonstration runs a 12 kV AC-to-800 VDC architecture and gathers field data on how medium-voltage DC infrastructure handles dense AI compute loads.
The Nexus Power Unit folds several pieces of conventional grid equipment (step-down transformer, switchgear and rectification) into a single modular system. Alderbuck says that consolidation cuts project capital costs by 20 to 30 percent, shrinks the physical footprint by a similar margin, shortens construction timelines by 30 to 50 percent and delivers up to 4 percent higher energy efficiency than a traditional AC power train. Those figures are the company’s own projections, and the SDSC deployment is designed to test them under real high-density load.
The project, titled “Accelerating Grid-Interactive, Flexible Data Centers in California,” is meant to produce operational field data on medium-voltage DC infrastructure and to build a flexible-load capacity tool that California policymakers and utilities can use to plan for large DC loads including AI data centers, EV fast-charging sites and industrial customers.
Why It Matters
AI racks are pushing power densities past what conventional 480-volt AC distribution was built for, and the industry is converging on 800-volt DC architectures to move more power through less copper. A medium-voltage solid-state transformer that converts 12 kV grid feed straight to 800 VDC removes several conversion stages and the switchgear that goes with them. If Alderbuck’s efficiency and footprint claims hold up in the SDSC field data, the design points toward faster, denser data-center buildouts, and the California Energy Commission’s flexible-load tool could shape how the state’s utilities plan for the DC loads now flooding their interconnection queues.
Critical Perspective
Alderbuck’s Nexus unit converts a 12 kV grid feed straight to 800 VDC and claims a 20 to 30 percent capital-cost cut, yet those savings are the vendor’s own projections that the San Diego demonstration has not yet tested. Competing 800-volt DC efforts from vendors such as Delta Electronics are chasing the same density gains, and none has published independently verified field data at data-center scale either. The FREEDM Systems Center at North Carolina State University spent more than a decade developing medium-voltage solid-state transformers that never reached commercial grid deployment, a reminder that lab-proven power electronics can stall on cost and reliability. If the technology were as bankable as the projected 30 to 50 percent construction-timeline cut suggests, why does it still need a California Energy Commission grant to run its first real-world load test?
Sources
- Alderbuck Energy: 800 VDC solid-state transformer deployment (Business Wire, June 23, 2026)
- Data Center Dynamics: Alderbuck to deploy solid-state transformer at San Diego Supercomputer Center
- Yahoo Finance: Alderbuck Energy 800 VDC platform at SDSC
