The U.S. electric grid is more than just power plants and transmission lines — it’s a web of connections among millions of small components, working together to allow you to flick on the lights when you walk in the door. That mechanical switch is only the last of many between the power plant and your home.

Researchers at the Department of Energy’s Oak Ridge National Laboratory are supporting the grid by improving its smallest building blocks: power modules that act as digital switches. That starts with tiny, semiconducting chips to construct faster, safer and more efficient power modules from scratch. “We’re going from the smallest semiconductor device all the way to the converter and application testing,” said ORNL researcher Brian Rowden.

Power modules manage grid equipment like converters and inverters, which regulate the type and flow of electrical current. Inverters are particularly vital to the U.S. clean energy transition because they connect the grid to electric vehicle chargers, wind and solar power.

The lab constructs modules, housed in an oblong case the size of a person’s hand, that control power moving through a system. ORNL engineers can rapidly move these components from development to evaluation because Rowden’s lab is co-located with low- and medium-voltage test beds in ORNL’s Grid Research Integration and Deployment Center, or GRID-C.