Why ex-SpaceX ‘Mother of Dragons’ Darby Dunn switched to building fusion

From March 2009 to December 2018, Darby Dunn held a handful of engineering and manufacturing roles at SpaceX.

“In one role in particular, my unofficial title was ‘Mother of Dragons,'” Dunn told CNBC in an interview in Devens, Mass. “In that role, I led the development of our new production facilities for the Crew Dragon vehicle.”

While she oversaw the production of the Dragon spacecraft, SpaceX went from ramping up production to creating its very first spacecraft, and then to regularly sending cargo to the International Space Station on it, Dunn says.

Building rockets is a very cool thing to do. But in January 2019, Dunn began working at Commonwealth Fusion Systems, a start-up attempting to commercialize nuclear fusion as an energy source. Fusion is how the sun and stars make energy. If it can be harnessed here on earth, it will provide virtually unlimited clean energy.

But so far fusion on a grand scale remains in the realm of science fiction.

Dunn says she made the transition from building rockets to working on making fusion energy a reality because she wants to see the impact of her efforts in her lifetime.

“I’m a big believer that SpaceX will make life multiplanetary. I don’t know how much of that I’ll see in my lifetime,” Dunn, 37, told CNBC in late May.

But Dunn has spent much of his life in California, where SpaceX is based, and has largely seen the effects of climate change in the form of wildfires and mudslides stemming from extreme rain.

“For me, it really came down to wanting to use my energy to clean up the planet instead of going off it. So that was the big shift for me to come to CFS,” Dunn told CNBC.

By joining Commonwealth Fusion Systems in its early stages, as its 10th employee, she has also been able to see another phase of the company’s growth journey.

“We’re a 5-year-old company with 500 employees,” Dunn told CNBC. “I joined SpaceX when it was 6 years old with about 500 employees. So I’ve actually been able to see the whole era that I didn’t get to experience at SpaceX and do at CFS.”

A key difference between the two jobs is the maturity of the respective industries.

“The aerospace industry has been around for a long time. So building a rocket engine, the mechanics of it looking very similar, or the structure itself, or the physics of how it works are all very, very well studied and very well understood,” Dunn told CNBC.

Fusion machines have been studied in academic settings and research labs since the early 1950s, but the entire industry is only in the very early stages of trying to prove that the science can have commercial applications. It’s being a part of that excitement that was a big draw for Dunn.

Of course, there are many skeptics who say the industry is the equivalent of Don Quixote tilting at his windmills. But Dunn says her time at SpaceX prepared her to face the skeptics.

“When Elon publicly said we were going to launch and land rockets back from space, everyone said, ‘That’s not possible! You can’t do that!'” Dunn said, referring to SpaceX CEO Elon Musk. SpaceX’s response was that the laws of physics say it’s possible, and so they were going to prove it, Dunn told CNBC.

“It took a lot of trying, a lot of learning, a lot of iterations on our software, a lot of failed attempts from the boat — and then we did it. And then we did it again. And we did it again. And we did it again. ,” she said .

“Now it’s gotten to the point where you’ve seen the aerospace industry shift to saying, ‘Well, why aren’t these other companies also lending their rockets back from space?’ It’s completely changed the way people look at it. At first they said, “It wasn’t possible. So “OK, it’s possible.” And now it says, ‘Well, why isn’t everyone else jumping in?’

Dunn is looking to be part of that kind of transition for the fusion industry in the Commonwealth.

Dunn is vice president of operations, covering manufacturing, safety, quality and facilities. She is helping the Commonwealth make the transition from research and development-scale processes to production and full-scale production.

The company spun out of research at the Massachusetts Institute of Technology and the company’s goal is to build 10,000 fusion power plants around the world by 2050, Dunn told CNBC.

First, however, the Commonwealth must prove it can generate more energy in the fusion reactor than is needed to start the reaction, a key threshold for the fusion industry known as “ignition”. To do so, the company is currently building its SPARC tokamak – a device that will help contain and control the fusion reaction. The company plans to turn it on in 2025 and demonstrate net energy shortly thereafter.

To build SPARC, the Commonwealth must make many magnets using high-temperature superconducting tape.

“The cool part of this building is that the concept for it started as a doodle that I made on a whiteboard three years ago,” Dunn told CNBC. “Seeing the steel beams go up, the walls go up, the concrete being poured, it’s a whole vision coming to life, which is super exciting.”

To fund construction, Commonwealth has raised more than $2 billion from investors including Bill Gates, Google, Khosla Ventures and Lowercarbon Capital.

Even as Commonwealth figures out how to make one magnet, Dunn is leading her team to develop manufacturing processes that can eventually be scaled to a process that looks like a car assembly line, she told CNBC.

Moving quickly is a priority for Dunn and the rest of the team. After building the demonstration fusion machine, SPARC, the company aims to build a larger version called ARC, which it says will supply power to the grid. The goal is to have ARC online in the 2030s.

“The biggest thing I think about a lot is time, about how fast we can go,” Dunn told CNBC. “The faster we can get the magnets built, the faster we can build SPARC, the faster we can turn it on, the faster we can get net energy in, the faster we get to our first ARC. So I think that’s probably the element that I think about most.”

Speed ​​matters because critics argue that it will take too long to get fusion working as an energy source to contribute meaningfully to the very urgent need to reduce greenhouse gas emissions.

Top climate scientists at the UN’s Intergovernmental Panel on Climate Change have said that to have “no or limited” excess warming of 1.5 degrees Celsius above pre-industrial levels would require a 45% reduction in carbon dioxide emissions by 2030 compared to 2010 levels and now net zero around 2050.

“I’ve asked myself, ‘Why am I doing fusion as opposed to something that’s going to deploy next year?'” she told CNBC. “For me, it comes down to the fact that fusion is the most energy-dense reaction in our solar system.”

But she does not believe that merger should be the only solution.

“I’m a big believer in solar and wind and a lot of other renewables — that we absolutely need them. We need those deployed now. We need those deployed all over the world,” Dunn told CNBC. “But I don’t think they will be enough to get us to 2050 and beyond.”

Electric cars, heat pumps, green steel and green cement all depend on having large amounts of clean electricity. Dunn’s focus is building the energy sources that the world will need in the decades and centuries to come.

If the Commonwealth is to deliver that solution, Dunn must first make a whole lot of very powerful magnets.

“My own personal opinion is that I’m going to keep going — keep building. And we have a poster on the back steps that says, ‘Keep calm and melt,'” Dunn told CNBC. “No matter what the world says, we work every day towards our goal of getting net-positive energy from fusion. And I’m looking forward to proving that to the world in a couple of years.”