Researchers at the Oak Ridge National Laboratory have developed more robust circuit breakers that are compatible with direct current. This development could lead to lower electricity costs, expanded capacity and a more stable electrical grid.

The electrical grid presently uses alternating current for transmission. TechXplore shared a report verifying that most modern circuit breakers are designed to work with this system. However, AC power is easily interrupted because the electricity flow changes direction 60 times per second.

Conversely, DC power flows in only one direction. While this makes it more difficult for a mechanical switch to react quickly enough in instances of system failure—such as if the current exceeds an intended magnitude, or if the current needs to be cut if a power line touches the ground—it’s also much more energy efficient.

The newly developed medium-voltage circuit breakers are capable of handling the growing electrical loads required by modern technology, while at the same time, increasing efficiency and lowering costs for customers.

“Developing this technology helps keep the grid working safely and reliably while keeping more energy available to support our growing population and economy,” said Prasad Kandula, ORNL research staff scientist and lead researcher for the project, in an August 2025 press release. “The lack of medium-voltage circuit breakers for direct current has been an obstacle to flexibility in delivering electricity.”

A study by Lawrence Berkeley National Laboratory indicates that there’s potential for a 7% reduction in energy consumption and a 28% efficiency gain when data centers, which are notorious for consuming large amount of electricity, use DC instead of AC power.

Because these medium-voltage circuit breakers under development use a semiconductor-based design that can operate a hundred times faster than mechanical switches, they enable wider use of DC in the electric grid, according to the press release. This efficiency is expected to convince energy system designers to create compatible systems. 

Historically, semiconductor breakers have been too expensive to compete with mechanical AC breakers, but Kandula believes his team has found a solution by reviving an older, industry-accepted semiconductor design that makes them more affordable.

To prove they can handle higher voltages, the team connected the breakers in a series and operated them up to 1,800V testing capacity. This is beyond the capacity that commercial DC breakers have been able to achieve.

Having addressed capacity, energy efficiency, safety and affordability, the researchers are preparing to add to the series in order to scale up to 10,000V in anticipation of the even higher electricity demands of future DC-based electrical grids.