Exploring Engineering Ep. 10: Nuclear Engineering

Conrad Buck
Hi. My name is Conrad Buck. I’m a third-year undergraduate studying Nuclear Engineering with a minor in EECS at Berkeley.

Laura Vogt
How did you decide to major in nuclear engineering?

Conrad Buck
It was initially pretty arbitrary. I kind of just picked it on the application. But as I came to Berkeley and learned more about the field and the state of energy production in the world—where we derive our energy sources from—and then learning about how nuclear energy is so much more incredibly dense than all of the other energy sources we use today, it really seemed like a pretty obvious choice, from my perspective, that this should absolutely be the future of energy.

That made me really excited to keep studying in the field, because a lot of it feels under-deployed to me. We already have a lot of the technology necessary to decarbonize the grid with nuclear power. It’s just waiting for a team of people to come along and really get that deployment going.

So I think that’s what made me stay in the major—because I’m just so excited for that future development.

Laura Vogt
Thank you to Conrad Buck for opening the Nuclear Engineering episode of Exploring Engineering at UC Berkeley. I had the opportunity to talk with Conrad a few months ago about his internship experience as an undergraduate.

I thought his path to nuclear engineering was interesting, since he hadn’t chosen the major for the major. Instead, he found his passion for the material through his classes and experiences as a student.

Hi, I’m Laura Vogt, Director of Student Communications for UC Berkeley Engineering’s Marketing and Communications team. I’m also the host and producer of this podcast, Exploring Engineering at UC Berkeley.
Nuclear Engineering has been a major at UC Berkeley for over 50 years and is the only Department of Nuclear Engineering at a university in California.

I’m now excited to introduce you to Isaac Duarte Valdez, a junior transfer to Nuclear Engineering. He had to choose his major before the Aerospace major was available for transfer students—and as a side note, Aerospace is available now for all undergraduates.

Isaac’s experience choosing a major then became a little different from what he was expecting. I’ll let him tell you more.

Isaac Duarte Valdez
My name is Isaac Duarte Valdez. I’m a senior transfer student. I’m a former undocumented student. In high school, when I was applying for colleges, I thought I wanted to be an aerospace engineer. I wanted to be an astronaut. And I was like, yeah, I mean—amazing! If I know how rockets work, then I’ll be able to be an astronaut.

When I was applying for Berkeley, I realized that they didn’t have an Aerospace Engineering program. So, when I was crawling through the options, it said Nuclear Engineering. And I was like, huh, I’ve never heard of Nuclear Engineering.

But with more research, I started liking it more because it encompassed a lot of the disciplines that I like. Beyond just aerodynamics, it encompassed chemistry, engineering, nuclear physics, particle physics, math, quantum physics, etc., etc. And I was like, well, if I can…

And there’s also nuclear engineers that have become astronauts. There’s the common misconception already—they focus on bombs, which is like, “Oh, you’re going into nuclear engineering because you want to build nuclear bombs,” which is not at all true.

Once I got into the major, in transfer, I realized—oh, wow—there’s actually a lot of branches that I did not think that there would be. It was so homogeneous, in a sense—either you go to this, or you go to that. But I do not repeat that; there’s so many branches, and I feel like I am getting to know the stuff that I’m interested in.

Laura Vogt
Our faculty insight into nuclear engineering is from Ellie Tubman. She’s a new faculty member here at Berkeley who has spent her time as a student, researcher, and professor experimenting and learning more about fusion.

I think her experiences with nuclear engineering will give you a great idea about what studying nuclear engineering can look like.

Ellie Tubman
I’m Ellie Tubman. I’m an assistant professor here at UC Berkeley in Nuclear Engineering.
I moved here from the UK, although I actually spent three years in the Bay Area working at Lawrence Livermore as a postdoc, working on the National Ignition Facility. I was there when we got the really exciting fusion results—we ignited our plasmas and created more energy out than we’d put into it, which was awesome.

I came into work that day and there were donuts out, and I was like, “Oh, what happened? What do we do?” And then they’re like, “You got a collision.” Wow. So that was a seriously cool day.

Laura Vogt
We’re taking a quick break from Ellie’s interview to talk about the fusion ignition she just mentioned.

It might sound funny that it was celebrated with donuts — but this was actually a pretty big deal.

First, a quick primer. Nuclear fusion is when two atoms smash into each other to form a heavier atom. In contrast, nuclear fission occurs when a neutron slams into a larger atom and splits it into smaller atoms. The main things to know about fusion is that it’s the same process that powers the sun, it generates way more energy than fission, and it doesn’t produce highly radioactive fission products. That’s why fusion is considered the holy grail of energy. It could lead to a clean, virtually limitless source of power. But fusion reactions are tricky. It turns out that positively charged atoms don’t want to merge naturally, so extreme temperatures and pressure are needed to, well, overcome that repulsion. 

So, when scientists at Lawrence Livermore National Lab reported in December 2022 that they sustained a nuclear fusion reaction long enough to get a net energy gain, it was buzzworthy.

Here’s what happened: They aimed a set of incredibly powerful lasers at a tiny pellet of hydrogen fuel. And for the first time ever, the reaction that followed produced more energy than the lasers used to start it.

This is called “ignition.”

This moment proved that fusion ignition is possible here on Earth. It’s something scientists have been chasing for over 60 years.

It’s kind of like the Wright brothers’ first flight — short, small, but the start of something that could change everything.

So, yes — scientists celebrated with donuts. But hey, when you recreate the power of the sun in a lab? You’ve earned a sprinkle or two.

Now, back to Ellie…

Ellie Tubman
Then I went back to the UK for a bit before coming back over to the States again to be part of the department here.

Fusion research is one of my primary areas now. I did an undergraduate degree in Physics at the University of Sussex. I went up to the University of York to do a Ph.D.—four years up there—where I did a lot of experiments and hands-on work, going to different facilities worldwide. I absolutely fell in love with the field of fusion.

Then I did a postdoc at Imperial College in London, where I worked for three years on a pulse power machine down in the basement. They always seem to hide these experiments down in the basements of these buildings and just tuck them away. But it was a fantastic lab—very much hands-on.

I’m a very hands-on, experimental person. I love being in a lab, building things, breaking things, working out why things work the way that they do.

We had this lab that was doing pulse power research. So we had lots of capacitor banks storing our energy, ready to discharge into these pulse-forming current lines, which then run up into your target. Our targets would often be wires—wire arrays—where, when you run the current through the wire, it heats the wire up and gives you a plasma.

But when you also have current running through a wire, you produce a magnetic field. And those magnetic fields can either act all together to pull the plasma into a pinch in the center or explode that plasma outwards. So we were doing experiments investigating plasma dynamics, such as shock waves or jets.

Now I’m actually working more on laser-driven fusion—going back to the work that I did on the National Ignition Facility at Lawrence Livermore Labs. I’m exploring some of the plasma physics dynamics of trying to understand magnetic fields being created within these environments.

So, in the same way we used magnetic fields in the pulse power lab to affect how the plasma moves, I want to see in a laser environment if we’re creating magnetic fields in the plasmas there that are affecting the way the plasma is moving in these fusion targets.

In nuclear engineering, there’s an awful lot of different projects. There are a lot of people in the department working on fission—fission reactors, looking at different components, how the neutrons might be affecting the materials around those reactors.

In my research, I’d say there’s fusion, and we can apply knowledge from fusion research to understanding astrophysical plasmas. A lot of the universe is made up of plasma, and we can apply what we learn in laser experiments to that.

There are also faculty working in nuclear engineering on detectors and diagnostics. You need ways to measure the conditions you’re producing. And sometimes the detectors are based on technologies from 20 years ago.

A lot of my research uses applications or diagnostic techniques commonly used in medical imaging or medical physics. Some of the detectors are films or cameras that they’ve stopped producing because the medical industry has moved on. And we’re like, “No, we’re still using this technology—please keep making the films!”

You need to have a good grasp of the math underlying nuclear processes. Coming from my background, I knew I enjoyed math. I knew I didn’t want to deep dive into lots of equation-heavy solving, but I did want to apply knowledge and question why things work the way they do.

In the nuclear engineering sense, it’s more about the materials you’re using and a lot of energy research—from fission to fusion power plants.

Laura Vogt
What do you think are the misconceptions out there about nuclear engineering?

Ellie Tubman
For me, especially coming from a physics background, I thought nuclear engineering was going to be these super dirty labs, lots of reactor engineering—more hands-on applications. And yes, those labs exist. But that’s not what it’s all about.

There are also an incredible number of clean lab spaces required in nuclear engineering.

Also, like with many science or engineering fields, I thought a lot of people in the field were going to be old white men—and that’s absolutely not the case. Actually, my research group and the undergraduates I work with are predominantly female right now. Even within the department, there are a lot of female professors—and incredibly good ones too—which is absolutely fantastic.

Laura Vogt
What do you think you’re most excited about right now in your research?

Ellie Tubman
One of the things I’m most excited about is that we’ve actually got this ignition result from fusion. For the last 50 years, everyone said fusion is only 30 years away. The National Ignition Facility even had “ignition” in the name—and for a long time, we hadn’t reached it. Simulations hadn’t been predicted accurately.

But now we’ve got ignition results, and we’re starting to see the energy we’re producing increasing. We’re improving how much energy we get out of these fusion experiments. So for me, it’s a really exciting time to be in the field.

There’s an awful lot of private fusion companies popping up, especially around the Bay Area. So there are a lot of people getting excited about it.

Laura Vogt
Nuclear Engineering studies energy, science, health, and security. Its students are trailblazers in nuclear energy, security, nuclear physics, nuclear chemistry, medical physics, and more.

This episode of Exploring Engineering is meant to be the beginning of your research into Nuclear Engineering. We encourage you to continue learning more by starting with our podcast page: engineering.berkeley.edu/exploringengineering, where you’ll find links to resources, videos, and more about all of the majors, programs, and departments here at UC Berkeley.

If you’ve enjoyed this or any of our other episodes, please share Exploring Engineering with your friends, classmates, and schools—giving others the chance to learn and explore what being an engineer means to you.