SolidUltra raises €3m to develop 800VDC solid-state transformers for AI data centers

SolidUltra has raised €3 million to develop modular solid-state transformers (SSTs) aimed at 800 VDC power distribution for AI data centers. The France-based company was incorporated in June 2026 and is backed by founding partner Watt & Well.

The funding is earmarked for product development, engineering, industrialization, and initial customer engagement ahead of a targeted commercial launch in 2028. SolidUltra is developing a medium-voltage SST intended to connect the electrical grid directly to 800 VDC in a single conversion stage, replacing a more traditional chain that uses a low-frequency transformer followed by multiple conversion steps.

On the technical side, the SST design targets 98.5% efficiency. SolidUltra also targets a 3× reduction in power losses and a 4× reduction in equipment footprint versus conventional architectures. The company further targets up to a 10× lower carbon footprint associated with power-conversion infrastructure, a time-to-power reduction from years to weeks through a modular, factory-built design, and around a 30% total cost of ownership reduction.

For operators, the move to 800 VDC is largely about pushing more power through less copper and fewer conversion stages as rack power climbs. If SolidUltra can hit anything close to its efficiency and footprint targets at medium voltage while keeping serviceability simple, it would directly affect white-space planning, cooling loads tied to conversion losses, and how quickly new capacity can be energized.

SolidUltra says its fully modular architecture is designed to scale from hundreds of kilowatts to 10 MW and beyond. Field-replaceable power modules are designed to be swappable in under 15 minutes, with the system designed to deliver 99.999% availability. The company links its roadmap to the broader industry shift toward 800 VDC architectures, including a transition NVIDIA has described for future generations of AI data centers.

“With rack power moving toward the megawatt scale, the industry needs to rethink the way electricity is converted and distributed inside data centers,” said Raul Iglesias, CEO of SolidUltra. “Securing €3 million only three months after our creation gives us the means to move rapidly toward industrial deployment.”

Following its targeted 2028 commercial launch, SolidUltra aims to scale production and, by 2032, deliver 10,000 SST modular systems representing about 1 GW of installed power. “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,” said Romain Beaume, CBO of SolidUltra.

SolidUltra was founded in June 2026. Watt & Well, its founding partner, manufactures power electronics and has manufacturing operations in France and the United States.