SolidUltra secures €3 million to develop power converters for AI data centers

SolidUltra has secured €3 million to develop equipment intended to simplify how electricity reaches AI data centers. The European company announced the funding on November 9, backed by founding partner Watt & Well. It is targeting a 2028 commercial launch—not offering a finished power system today.

A startup built around the power transition

Founded in June 2026, SolidUltra is responding to what it describes as a shift toward megawatt-scale racks of graphics processing units, or GPUs. The company says those denser computing installations are driving preparations for 800-volt direct-current power distribution, shortened to 800VDC.

Its response is a modular solid-state transformer: power-conversion equipment designed to connect the medium-voltage electrical grid directly to that 800VDC architecture. Rather than build the business entirely from scratch, SolidUltra is drawing on Watt & Well, a French power-electronics group that it says already manufactures equipment at gigawatt scale.

The new money will fund product development, engineering, preparation for industrial production and initial customer engagement. Those are the immediate uses of the financing; the commercial equipment and the performance gains described in the announcement remain part of the development plan.

Replacing several conversion stages with one

SolidUltra describes the conventional data-center power chain as a low-frequency transformer followed by several conversion stages before electricity reaches the computing equipment. It says rising GPU power consumption makes that arrangement increasingly restrictive, adding energy losses, cooling demands, equipment space and delays in getting power ready.

The proposed system would perform grid-to-800VDC conversion in a single stage. SolidUltra is targeting 98.5% efficiency, one-third of the power losses and one-quarter of the equipment footprint of conventional architectures. These are company targets, not independently verified operating results.

The design also aims to change how operators add and maintain capacity. Factory-built modules are intended to let customers increase power progressively, rather than treat the entire installation as one fixed unit. SolidUltra says its architecture would scale from hundreds of kilowatts to 10 megawatts and beyond.

Other design targets

• Maintenance: field-replaceable power modules designed to be swapped in under 15 minutes, supporting a stated availability target of 99.999%.
• Ownership costs: around 30% lower total cost of ownership through the modular, factory-built approach.
• Carbon footprint: up to a tenfold reduction associated with the power-conversion infrastructure, rather than a claim about the entire data center.

Today, data center operators can wait years to get power to new AI capacity; we want to deliver it in weeks, with lower losses and a footprint four times smaller. Our ambition is to build a European industrial player capable of serving the market on a global scale

Romain Beaume, chief business officer, SolidUltra

From development money to factory output

Watt & Well brings an existing manufacturing base to that ambition. Founded in 2008, it designs and manufactures power electronics for electric mobility, energy, space and defense. It has manufacturing capabilities in France and the United States, and supports customers from research and development through series production.

Beyond the planned 2028 launch, SolidUltra has set a 2032 production ambition: 10,000 modular transformer systems representing approximately one gigawatt of installed power. That is a future deployment goal, not a disclosed order book. The next step funded by this announcement is engineering and industrialization, alongside the initial customer work needed before commercial deployment.