Enphase tests a new path for AI rack power

Enphase tests 13.8 kV-to-800 V data-center power

A lab milestone for rack power

Enphase said October 27 that its Austin laboratory demonstrated conversion from 13.8 kilovolts of alternating current to 800 volts of direct current. The company reports that its IQ Solid-State Transformer held the output steady during simulated changes in AI rack demand.

The test used 132 modules, arranged as 44 in series on each of three phases. Enphase says its controls shared voltage across the modules. This is a company-reported development test; customer pilots remain planned for 2027.

Source: Enphase Energy announcement · Oct 27, 2026

What the conversion changes

Alternating current reverses direction; direct current flows in one direction. Voltage conversion and AC-to-DC conversion are separate electrical tasks, even when equipment combines them. A data center needs power delivered in a form its equipment can accept, not simply a large electricity supply at its boundary.

Enphase aims to reduce the number of conversion stages between medium-voltage power and an 800-volt DC architecture. Fewer stages could reduce losses, but this release provides no measured whole-facility efficiency improvement. That distinction matters when comparing an equipment demonstration with an operating data center.

The next tests still lie ahead

Enphase plans a 34.5-kilovolt demonstration, followed by megawatt-scale rack testing at rated power before year-end. Those milestones are forecasts, not completed deployments.

For readers assessing the result, the useful next evidence would include measured efficiency across different loads, sustained operation and customer-pilot results. A successful voltage-conversion test answers one engineering question; it cannot by itself answer what an installed system costs or how reliably it will run over years. Nor does more efficient conversion create a new source of electricity or establish savings on household bills.

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