Enphase Energy is developing the IQ Solid-State Transformer (IQ SST), a distributed solid-state transformer platform aimed at AI data centers as operators push toward higher-density DC power architectures.
The IQ SST is built around a rack-scale power block: each 1.25 MW IQ SST rack combines 342 intelligent, semiconductor- and software-defined power modules in a coordinated series/parallel configuration. Enphase expects the system to deliver 98.5% efficiency and 99.999% availability, using built-in redundancy that’s intended to keep the rack operating with only 90% of modules participating.
One notable design choice is the absence of internal batteries. In supported configurations, Enphase intends IQ SST to reduce or eliminate the need for rack-level battery sidecars and traditional UPS systems. For data center electrical rooms and white-space layouts, that’s a direct trade: fewer conversion and energy-storage boxes could mean more usable floor space for compute. But the practical question for engineers will be how those “supported configurations” are defined, because UPS replacement touches fault ride-through, maintenance windows, and how the facility handles upstream disturbances.
Electrically, IQ SST is designed to convert medium-voltage AC directly into regulated DC in a single conversion stage, including 35 kV and 15 kV interconnection classes. The platform is designed to support both 800 VDC and ±400 VDC rack configurations tied to emerging AI data center standards, with sub-millisecond response to dynamic AI load changes.
At the module level, Enphase says the IQ SST power module is derived from its microinverter platform (ninth generation) and uses the company’s fifth-generation control ASIC, “Kestrel,” a custom 22 nm chip intended to coordinate fast response across hundreds of distributed modules. The design also uses gallium nitride (GaN) switching technology that Enphase says is proven in its IQ9 microinverters.
On manufacturing, Enphase expects to build IQ SST on the same automated platform it has used to ship approximately 87.8 million microinverters. The company says the power modules are designed around standard high-volume semiconductor components and can be supplied from manufacturing facilities in the United States.
“As AI racks move toward 800 VDC (±400 VDC) architectures and megawatt-scale densities, we believe that distributed architecture is well suited to this transition, and it is what we are building,” said Badri Kothandaraman, president and CEO of Enphase Energy.
Enphase expects full system demonstrations of IQ SST late this year, customer pilots in 2027, and volume shipments in 2028. Raghu Belur, co-founder and chief product officer, said, “A single-stage, semiconductor- and software-defined, distributed design is how we intend to deliver the performance, reliability, and economics that AI data centers need.”
