A flat, pancake-shaped device the size of a small stop sign could recover megawatts of electricity now wasted as heat inside the data centers powering AI.
GOLDEN, Colo. — Engineers at the National Renewable Energy Laboratory have built a power conversion module that reduces energy losses during electricity delivery by seven to nine times compared to existing commercial devices, the lab announced. The module, called ULIS, is designed for data centers, EV chargers, and industrial power systems that account for a fast-growing share of global electricity consumption.
The device uses silicon carbide, a material that handles higher voltages and temperatures than conventional silicon, in a flat octagonal design that eliminates most of the electromagnetic interference that bleeds energy away during power conversion. NREL has made ULIS available to license for commercial development.
“It’s a future-proofed, ultrafast power module that will make the next generation of power converters more affordable, efficient, and compact,” said Faisal Khan, NREL’s chief power electronics researcher and the project’s principal investigator.
The energy lost before it reaches a server
Global data center electricity consumption hit a record high in 2024, roughly doubling its recent average annual growth rate, according to the International Energy Agency. Most attention has focused on AI chip efficiency or expanding power generation. Less attention has gone to a different problem: the energy lost simply moving electricity from the grid to the hardware that uses it.
Every server, electric vehicle, and industrial machine requires electricity delivered at a specific voltage and current. Raw power from the grid must be converted, stepped up, stepped down, and reshaped, before it reaches any device. That conversion happens inside a power module, and every conversion wastes some electricity as heat.
The central engineering challenge in power modules is a property called parasitic inductance, essentially electrical inertia that slows switching speed and increases losses with every cycle.
Reducing it has been a core research problem in power electronics for decades. NREL’s team reduced it in ULIS by seven to nine times compared to any existing silicon carbide module on the market.
A flat design that solved what three-dimensional shapes couldn’t
The breakthrough came from abandoning conventional module geometry. Standard power modules are brick-shaped. The NREL team tested more complex arrangements, including flower-shaped layouts and hollow cylinders wired from the inside, before arriving at a flat octagonal form roughly the size of a stop sign.
“We squished it flat, like a pancake,” said Shuofeng Zhao, the NREL researcher who designed the module’s architecture. “And suddenly we had a low-cost, high-performing design that was much easier to fabricate.”
The flat shape maximizes magnetic flux cancellation, reducing the electromagnetic interference that causes energy loss during each switching cycle. Combined with a novel current routing design, the result is switching that is both faster and cleaner. ULIS operates at 1,200 volts and 400 amps and achieves five times greater energy density than previous designs in a smaller package.
Manufacturing cost drops from thousands to hundreds of dollars
High-performance power modules have traditionally been manufactured by bonding copper sheets to rigid ceramic bases, a process that requires specialized equipment and expensive materials. ULIS bonds copper to a flexible polymer called Temprion using pressure and heat, and can be machined with widely available equipment.
That brings manufacturing cost down from thousands of dollars per unit to hundreds, a reduction the team says is the difference between a laboratory device and one ready for commercial adoption.
The module also monitors its own health in real time and can predict component failure before it occurs. It operates wirelessly, with no external cables required for control or monitoring, making it compatible with systems ranging from data center racks to aircraft.
Target applications
Data centers require power conversion at every stage, from grid connection down to individual server racks. Each stage where ULIS replaces an older module recovers electricity that would otherwise be lost as heat. At data center scale, those efficiency gains translate to megawatts of recovered power.
NREL identifies EV charging infrastructure, industrial power grids, and pulsed power systems for future fusion reactors as additional target applications. The lab has made the module available for licensing, indicating it is ready for commercial partners rather than further laboratory development.
Source: NREL. “NREL Researchers Build World’s Fastest, Low-Cost, Ultraefficient Silicon Carbide Power Module.” National Renewable Energy Laboratory, September 10, 2025. Note: This research was originally published in September 2025 and received renewed attention in January 2026.
Quotes in this article are drawn from a press release issued by the National Renewable Energy Laboratory on September 11, 2025.