Piles of snow and bitter cold didn’t deter U.S. congressional representative Don Beyer from meeting with UMBC’s Carlos Romero Talamás in late January to discuss the hot topic of fusion energy. Fusion reactions, which release massive amounts of energy when multiple light atomic nuclei merge to form a single heavier nucleus, power the Sun, and it is hoped they will soon deliver clean, reliable, and abundant energy generation on Earth, too. 

Rep. Beyer, of the 8th District of Virginia, founded and co-chairs the bipartisan Congressional Fusion Energy Caucus, dedicated to advancing fusion energy technology, while Romero Talamás, an associate professor of mechanical engineering, leads a laboratory exploring a novel fusion energy concept that may offer an easier path to a commercially viable reactor. During the visit on January 29, Romero Talamás gave Beyer a tour of the lab, which is located on the University of Maryland, College Park campus and brings together faculty and students from both UMBC and UMD. 

A simpler fusion machine

Images captured by NASA’s Solar Dynamics Observatory show loops of hot plasma trapped by the Sun’s magnetic field. A solar flare flashes on the left side. (Credit: NASA/GSFC/SDO)

The centerpiece of the lab is a large machine where the researchers have been testing a relatively new approach to confining plasma—the unruly soup of particles that forms when gas gets super hot. At high enough temperatures (typically more than 100 million degrees Celsius on Earth) and densities, particles in a plasma can slam into each other with enough energy to fuse together. 

The Maryland group’s confinement approach, called a centrifugal mirror, traps the blazing hot plasma in a linear tube with strong magnetic fields at the ends that push charged particles toward the center (the magnetic mirror), while also whipping them at supersonic speeds around a central conducting rod (the centrifugal part). The rotation creates stabilizing forces that can pull a plasma back together in the face of inherent instabilities that threaten to rip it apart. 

Recent experiments confirm that the physics used to model the confinement approach accurately predicts its real-world behavior, giving the researchers confidence that they could take the approach all the way to a working fusion reactor.

In fact, Romero Talamás has founded a company, called Terra Fusion, to do just that. The company has offices in College Park and is currently looking for laboratory space in Baltimore where it can build a next-generation machine. 

The start-up joins a host of other fusion companies, primarily in the U.S. The entire field has attracted billions of dollars in private investments, including from such big players as Microsoft co-founder Bill Gates and OpenAI CEO Sam Altman. While Romero Talamás’ company is just getting started, he’s confident Terra Fusion can catch up and overcome competitors because of its relatively compact, inexpensive, and simple machine design.

Many approaches to building a fusion reactor rely on strong magnetic fields to contain the hot plasma. (Marlayna Demond ’11/UMBC)

All the companies still face big engineering hurdles, such as finding materials that can withstand the punishing onslaught of particles and radiation within the reactor. A simpler machine should make the path to overcoming these challenges much easier. 

Public-private partnerships fuel innovation

Fusion research in the U.S. in recent years offers an example of how the public and private sectors can work in tandem to address daunting challenges. The initial experiments on the current centrifugal mirror machine were funded by the U.S. Department of Energy. Once those experiments confirmed the promise of the approach, private sector investment jumped in. Romero Talamás says the U.S. government also supports private sector research by offering companies access to the specialized expertise, experimental facilities, and advanced modeling capabilities at the national laboratories. 

U.S. fusion experts hope the jostle of competing commercial ideas will shorten the time it takes to demonstrate a fusion reactor design that could meet a significant portion of humanity’s ever-growing energy demands more cleanly, cheaply, and reliably than alternative energy approaches. Despite the proliferation of groups vying to make the next big fusion breakthrough, a mostly collaborative spirit still prevails within the research community, Romero Talamás says. “If any one of these technologies succeed,” he points out, “it will benefit us all.”