The iron transformer is the 140-year-old technology that supports both the power grid and AI companies. The devices are clunky but reliable, which explains why they’re still used: If it ain’t broke, don’t fix it.
But as data center power demand soars and batteries and renewables carve out larger parts of the grid, the ancient technology may eventually reach its limits. Fortunately, their electronic replacement – the solid-state transformer – could be having its moment, and not too soon.
In recent months, startups specializing in solid-state transformers have raised $280 million. The technology promises to reduce the number of components needed in data centers, improve network stability and shrink the footprint of power conversion equipment.
Now, Overscale power he says he can narrow things down further. “We haven’t seen anything as small as our system will be,” Daniel Rothmund, co-founder and CEO of Hyperscale Power, told TechCrunch.
To build a prototype of the transformer, Hyperscale recently raised a €5 million round led by World Fund and Vsquared Ventures, the company exclusively told TechCrunch.
In the last couple of years, the solid state transformer market has gone from almost non-existent to almost crowded. Competitors include Amperesand, which was incubated by Temasek’s early-stage fund. DG Matrix, which counts industrial giant ABB as an investor. and Heron Power, which was founded by former Tesla executive Drew Baglino and is backed by Andreessen Horowitz. Together, they have raised over $330 million, according to PitchBook.
Hyperscale seems to be late to the party, but both Rothmund and co-founder Sami Pettersson have been working on the technology for a while. Rothmund, specifically: He completed his PhD at ETH Zürich in part by designing and building a 99.1% efficient solid-state transformer.
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All solid-state transformers are smaller than their iron-core equivalents, but Hyperscale says it has a way to go further by building a transformer that can operate at much higher frequencies than competitors. When the power enters the transformer, it will increase to something in the range of tens of kilohertz. It is converted to the required voltage and then stepped down to the required frequency.
Size matters more and more in data centers as the power density of server racks increases. The latest Nvidia racks consume more than 100 kilowatts of power, and the company is already preparing for 1 megawatt racks, enough to power up to 1,000 homes.
At these scales, the transformers and rectifiers needed to prepare the electricity for the servers will grow in size. “It’s more than twice the size of the server racks themselves,” Rothmund said.
Aggressive roadmaps being developed by AI companies and data center developers have made solid-state transformers almost a necessity, he said.
“It’s really going to slow down progress in data center scaling if you don’t have solid-state transformers ready very soon,” Rothmund said. “It’s not a question of if solid-state transformers will come, it’s a question of when.”
