California-based power electronics maker Enphase announced it developed a new solid state tranformer technology for next-generation data center power infrastructure, including emerging higher-voltage direct current (DC) rack power architectures for AI workloads.

Instead of using one large, centralized converter, Enphase Energy’s IQ Solid State Transformer (IQ SST) converts power in data centers to 800 V DC using 342 small power modules per standard 1.25 MW rack to achieve up to 98.5% efficiency.

This distributed approach is key to retaining 99.999% availability amid the volatile power swings that plague data centers and make them a drain on electricity grids, the company said.

Power swings and power conversion from legacy medium-voltage AC systems to high-voltage DC architecture are both ongoing issues for data center operators when it comes to grid behavior.

A report titled Key Questions on Energy and AI by the International Energy Agency (IEA) warned that the unpredictable power swings caused by AI data center workloads will increase in severity as the power density of AI hardware increases and GPUs become more advanced.

“For power delivery, the key challenge is to minimize the space and material footprint of power supply equipment, minimize capital costs and lower electricity conversion losses power losses and generate substantial amounts of heat, which would need to be managed in addition to the heat produced by the IT equipment,” the report stated.

Gallium-nitride-based power electronics present one of several viable solutions to the space saving problem for power conversion, according to the IEA report authors. However, they pointed out that China controls 99% of the supply. They also listed silicon carbide-based power electronics, lithium-ion and sodium-ion batteries and ferrite cores for solid-state transformers as solutions.

Enphase’s IQ SST is built on gallium-nitride-based semiconductors using distributed architecture.

 “We’ve spent two decades showing that distributed beats centralized, first in solar, then in batteries, and this is that same bet applied to data center power,” Enphase Energy’s senior director, corporate communications, Andy Newbold, told pv magazine.

At the end of June, Enphase Energy joined the Open Compute Project (OCP) Foundation as a platinum member to share its IQ SST platform with the foundation’s nearly 700-strong network of individuals and organizations collaborating to design next-generation computing hardware.

Enphase is getting involved because power architecture is not something that should be solved behind closed doors, Newbold said.

“These standards are being written as we speak, while the industry moves to 800 VDC. What we bring to that is two decades of building distributed, semiconductor- and software-defined power electronics, and actually manufacturing it at volume,” said Newbold.

Enphase Energy’s IQ SST, first announced in April, converts medium-voltage AC at the 15 kV and 35 kV interconnection classes straight to regulated 800 VDC in one stage. This approach “collapses a chain of transformers and converters down to a single step,” said Newbold.

The power module used in the IQ SST comes out of Enphase’s ninth-generation microinverter. It uses the same gallium nitride (GaN) power switching technology, and it is coordinated by the company’s fifth-generation control ASIC ‘Kestrel’ custom 22-nanometer chip. Enphase will manufacture the IQ SST on the same automated platform it has used to ship millions of its microinverters, and the power modules can be built from standard high-volume semiconductor components and supplied to manufacturing facilities in the United States, tapping into the company’s existing supply chain.

Newbold explained that because the IQ SST platform can run without internal batteries, it cuts down or removes the rack-level battery sidecars and uninterruptible power supply (UPS) systems operators normally have to plan around and make additional space for on the floor of the data center. “For data center developers, when every square foot is competing with compute, handing space back to the racks is worth real money,” said Newbold.

He said Enphase’s work with the OCP Foundation will be about sharing “real engineering”. While the focus is on data centers for the moment, Newbold told pv magazine that demand for the same distributed, software-defined architecture could extend into other large high-power markets. At the moment, it forecasts demand in the United States to exceed 11 GW by 2031, although this is just an initial estimate.

“We can see it supporting things like utility-scale solar, batteries, and high-power EV charging down the road,” he said, adding Enphase expects full system demos later this year, with customer pilots to follow in 2027 and volume shipments expected in late 2027 or early 2028.