Why the ‘Mother of Dragons’ at SpaceX left her job building rockets to work on nuclear fusion

From March 2009 to December 2018, Darby Dunn held several engineering and manufacturing positions at SpaceX.

“In one role in particular, my unofficial title was ‘Mother of Dragons,'” Dunn told CNBC in an interview in Devon, Massachusetts. “In this role, I led the construction of our new manufacturing facilities for the Dragon crew vehicle.”

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

Building rockets is a very cool thing. But in January 2019, Dunn started working at Commonwealth Fusion Systems, a start-up company trying to commercialize nuclear fusion as an energy source. Nuclear fusion is how the sun and stars produce energy. If it could be used here on Earth, it would provide virtually unlimited clean energy.

But for now, fusion at scale remains in the realm of science fiction.

Dunn says she switched from building rockets to working to make fusion power a reality because she wants to see the impact of her efforts throughout her life.

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

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

“For me, it really came down to wanting to use my energy to clean up the planet instead of getting away from it. So that was the huge change for me to come to CFS,” Dunn told CNBC.

Joining Commonwealth Fusion Systems in the early stages, as its 10th employee, also allowed her to see a different stage of the company’s growth path.

“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 actually got to see the whole era that I didn’t get to experience at SpaceX and doing that at CFS.”

A key difference between the two professions 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 seem really similar, or the structure itself, or the physics of how it works, it’s all very, very well studied and very well understood,” Dunn told CNBC.

Fusion machines have been studied in academia and research labs since the early 1950s, but the industry as a whole is only in the early stages of trying to prove that the science can have commercial applications. Being a part of that excitement was a big draw for Dunn.

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

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

“It took a lot of trying, a lot of learning, a lot of iterations of our software, a lot of failed attempts outside 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 space industry change to say, ‘Well, why aren’t these other companies lending their rockets from space, too?'” It’s completely changed the way people look at it. They first said, “It’s not possible. Then “OK, it’s possible.” And now he says, “Well, why doesn’t everybody else get involved?”

Dunn wants to be part of that kind of transition for the Commonwealth’s fusion industry.

Dunn is vice president of operations, covering manufacturing, safety, quality and facilities. It is helping the Commonwealth make the transition from R&D-scale processes to manufacturing and full-scale production.

The company spun off from MIT research, and the company’s goal is to build 10,000 fusion power plants worldwide by 2050, Dunn told CNBC.

First, however, the Commonwealth must prove it can generate more energy in its fusion reactor than is needed to start the reaction, a key threshold for the fusion industry called “ignition”. To do this, the company is currently building its SPARC tokamak, a device that will help limit and control the fusion reaction. The company plans to turn it on in 2025 and demonstrate clean energy soon after.

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

“The cool part about this building is that the concept for it started as a doodle I did on a whiteboard three years ago,” Dunn told CNBC. “To see the steel beams go up, the walls go up, the concrete pour, it’s a whole vision that comes to life, which is super exciting.”

To finance construction, the Commonwealth raised more than $2 billion from investors including Bill Gates, GoogleKhosla Ventures and Lowercarbon Capital.

While Commonwealth figured out how to make a magnet, Dunn led her team to develop manufacturing processes that could eventually scale to a process that resembles an assembly line for cars, she told CNBC.

Moving fast 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 electricity to the grid. The goal is to have ARC online in 2030.

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

Speed ​​matters because critics say it will take too long for fusion to work as an energy source to make a significant contribution to the much-urgent need to reduce greenhouse gas emissions.

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

“I asked myself, ‘Why am I doing fusion and not something that’s going to be deployed 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 doesn’t believe fusion should be the only solution.

“I’m a big believer in solar, wind and many other renewable energy sources – that we absolutely need them. We need those deployed now. We need those deployed around 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 depend on the availability of large amounts of clean electricity. Dunn is focused on building the energy sources the world will need for decades and centuries to come.

If the Commonwealth is going to provide this solution, however, Dunn must first make a whole bunch of very powerful magnets.

“My personal opinion is that I will continue – I will continue to build. And we have a poster on the back stairwell that says ‘Keep Calm and Fire Up,'” Dunn told CNBC. “Regardless of what the outside world says, we work every day towards our mission of getting net positive energy from fusion.” And I’m looking forward to proving that to the world in a few years.”