Deep Tech Venture Capital • Climate • Nuclear

Rachel
Slaybaugh

She once operated a nuclear reactor as an undergrad. Now she decides which companies get funded to build the next one.

General Partner DCVC Climate Tech Nuclear Engineer, PhD San Francisco
Rachel Slaybaugh, General Partner at DCVC

Rachel Slaybaugh • General Partner, DCVC • San Francisco, CA

Latest Promoted to General Partner at DCVC in 2024 - backing Radiant Industries' $300M+ Series D for portable nuclear energy at scale

The Physicist Who Backed the Companies She Couldn't Build in a Lab

In the summer of 2022, Rachel Slaybaugh did something that confounded a lot of her colleagues: she left a tenured professorship at UC Berkeley. She doesn't spend much time explaining the decision. "The timeline to impact I wanted to have - and the distance to impact I wanted to be much closer." That's enough.

Today, as a General Partner at DCVC - one of the original deep tech venture firms in Silicon Valley - Slaybaugh writes checks into the companies trying to solve the energy transition. Not the easy ones. The ones dealing with geothermal wells drilled sideways through granite, microreactors designed to power a remote military base, and cement that doesn't emit CO2 when it cures. Her portfolio reads like the syllabus of a very serious graduate seminar on energy physics.

What makes her unusual in venture is not the technical depth, though that's formidable - her PhD research was in numerical methods for neutron transport on supercomputers. It's the full span of her prior career. She ran an accelerator. She ran programs at a federal agency. She started a bootcamp that is still running. She co-founded a policy organization. She has the institutional map in her head that most investors have to hire consultants to draw.

DCVC's position is deliberate: "You can do good for the world in a traditional venture model, and in fact we should." Slaybaugh embodies that bet - she does not run an impact fund, she runs a fund that happens to believe the most important companies to back right now are the ones solving climate at industrial scale.

"We have billions of people on the planet and trillions of dollars in embedded infrastructure - you just can't turn systems that quickly."
- Rachel Slaybaugh, MCJ Climate Podcast
30+ Companies funded through ARPA-E nuclear fission programs
3 Nuclear programs created at ARPA-E: MEITNER, LISA, GEMINA
8 Years as tenured professor at UC Berkeley
5+ Portfolio board seats: Fervo, Fourth Power, Radiant, Equilibrium, Brimstone

The Scholarship That Rewired a Career

In 2002, Rachel Slaybaugh was a freshman at Penn State looking for a scholarship for women in the sciences. The one she found pointed her toward nuclear engineering. She took it. She walked into the Penn State research reactor building - a 1950s-era facility that few people on campus knew existed - and became a licensed nuclear reactor operator before she finished her undergraduate degree.

She hadn't planned on nuclear. She planned on engineering in a general sense. But the physics held her. "There's a large, existing, base load source of electricity that doesn't emit air pollution," she recalls thinking, even as a freshman. That clarity - nuclear for climate reasons - has never left her. It predates careers, titles, and funding rounds.

Before she got to Penn State, she had already written an editorial about recycling in third grade. The climate concern wasn't new; it was waiting for a technical channel. Nuclear engineering provided it.

From the Reactor to the Research Front

She went to the University of Wisconsin-Madison for her graduate work - a master's and PhD in nuclear engineering and engineering physics, with a certificate in Energy Analysis and Policy. Her research was computational: numerical methods for neutron transport with an emphasis on supercomputing, applied to reactor design, radiation shielding, and nuclear security.

It was dense, specialized work. She got good at it. And then she noticed something: the constraints holding nuclear back were not the equations. "What was holding nuclear energy back was not high-performance supercomputing." That realization - that the bottleneck was elsewhere, in commercialization, in policy, in entrepreneurial infrastructure - changed the shape of her career.

She joined UC Berkeley as a faculty member in nuclear engineering, got tenured, and started looking for faster ways to move the needle. She found three, in rapid succession.

"I decided to come to ARPA-E because it's a unique opportunity to be able to change the trajectory of energy technologies. ARPA-E brings new ideas to the forefront and brings together new communities to think differently about old problems."
- Rachel Slaybaugh, ARPA-E

Three Jobs Compressed Into One Resume

The Bootcamp Builder

In 2016, Slaybaugh launched the Nuclear Innovation Bootcamp at UC Berkeley. The premise: nuclear researchers are often excellent scientists and terrible entrepreneurs. The bootcamp ran two weeks and taught them how to think about commercialization, talk to customers, and build companies. It grew into an annual event. It's still running. She described it as "a giant stride forward in the clean energy race" - and then kept moving.

The Federal Programs Architect

At ARPA-E - the Department of Energy's high-risk, high-reward research agency - Slaybaugh served as a Program Director with an unusually wide brief. She created the nuclear fission program from scratch, developing MEITNER (focused on enabling technologies for microreactors), LISA (low-dose radiation research), and GEMINA (advanced nuclear maintenance). She helped issue awards to over 30 companies and teams.

But her portfolio at ARPA-E didn't stop at nuclear. She also managed the TERRA and ROOTS agriculture initiatives, solar programs, and even a virtual reality portfolio. The span was deliberate. Working across energy sectors gave her a systems-level perspective that pure nuclear specialists don't get. It's what she later brought to venture: the ability to evaluate a geothermal play through the same framework as a cement company.

One unexpected moment during this time: when the Trump administration attempted to defund ARPA-E in its first term, Congressional pushback was so strong that the agency's budget roughly doubled. "The Trump administration trying to shut down ARPA-E caused Congress to become really supportive," she noted, with some bemusement.

The Cyclotron Road Director

At Lawrence Berkeley National Laboratory, Slaybaugh ran the Cyclotron Road Division - a translational research program that supports early-stage scientists trying to move from the lab to the market. Cyclotron Road is one of the better-designed bridges between national laboratory research and venture-backed startups. She understood that bridge from both sides.

The Policy Co-founder

In 2020, while doing all of this, Slaybaugh co-founded the Good Energy Collective - a policy research organization that advocates for nuclear energy as part of the national climate strategy. She chairs the board. The organization is a direct expression of one of her core arguments: "You need policy to help set the direction... you also need technology to make the job of policymakers easier." Neither can wait for the other.

The Venture Capitalist

She joined DCVC in April 2022 as a Principal. In 2023 she was promoted to Partner. In 2024, to General Partner. The progression was fast - which is what happens when someone arrives with the institutional knowledge, the technical depth, and the deal judgment already assembled. DCVC simultaneously launched its first dedicated climate fund.

Her investment thesis rejects binary thinking. She doesn't believe in a single technological solution to the energy transition: "We need so much electricity... we need all of the things. We need the things that we have today, and developing the tools we are going to need tomorrow." Geothermal, fusion, microreactors, carbon-free cement, grid management software - these are not in competition. They are parallel tracks in a very large problem.

She is also notably pragmatic about political risk. DCVC explicitly avoids companies whose business models depend on specific policies or carbon markets. Her view: bet on companies that are economically viable within current market conditions, and let policy tailwinds be upside, not thesis. That framework survived November 2024 well.

On working with fossil fuel companies - a sector that many in climate tech treat as an adversary - she is unusually direct: "Anytime you're in a trying to take someone down stance you're probably going to end up using a lot of resources on a fight." The drilling expertise that built the oil industry is the same expertise that can build geothermal fields. She'd rather use it.

Signature Move

Left a tenured Berkeley professorship - and never looked back. The answer, when people ask, is short: she wanted to be closer to impact.

What DCVC Looks For

Technical risk at pre-seed? Fine. Policy-dependent revenue? Hard pass. Companies economically viable today that don't need regulatory changes to win.

Field Notes

  • Wrote about recycling in 3rd grade. The climate concern is 30+ years old.
  • Licensed nuclear reactor operator before graduating undergrad.
  • Her ARPA-E portfolio spanned nuclear, agriculture, solar, and virtual reality.
  • Co-founded two organizations while still a professor.
  • Enjoys dancing, hiking, and good conversation.
  • Backed Fervo Energy (geothermal) despite being a nuclear engineer - a signal of portfolio-wide thinking, not tribal loyalty.
  • Pronouns: she/her

Companies She's Betting On

DCVC's climate portfolio - assembled with Slaybaugh's fingerprints across energy, materials, and infrastructure.

Fervo Energy
Enhanced Geothermal

Using horizontal drilling and distributed fiber sensing to unlock geothermal energy at scale. Board member since February 2024, People & Culture Committee Chair.

Board Member
Radiant Industries
Microreactors

Building portable nuclear microreactors for remote power applications. Raised $300M+ Series D. Board member since November 2024.

Board Member
Brimstone
Decarbonized Cement

Producing calcium silicate rock-based cement that is carbon negative - targeting one of the hardest-to-abate industries. Board observer since March 2022.

Board Observer
Fourth Power
Grid-Scale Energy Storage

Long-duration thermal energy storage using graphite blocks heated to 2,400C. Board member since November 2023.

Board Member
Equilibrium Energy
Grid Management Software

AI-driven platform for optimizing energy grid operations and storage dispatch. Board member since December 2023.

Board Member
Zap Energy
Fusion Energy

Shear flow-stabilized Z-pinch fusion approach - no magnets required. DCVC portfolio company, one of the most watched fusion bets in venture.

Investor

What She Actually Says

"We need so much electricity... we need all of the things. We need the things that we have today, and developing the tools we are going to need tomorrow."
On the energy transition portfolio approach
"You can do good for the world in a traditional venture model, and in fact we should."
On DCVC's climate investment thesis
"Anytime you're in a trying to take someone down stance you're probably going to end up using a lot of resources on a fight."
On collaborating with fossil fuel industries
"You need policy to help set the direction... you also need technology to make the job of policy makers easier."
On the policy-technology relationship
"It wasn't evident what some of the victories for cleantech 1.0 were - it took a little time."
On lessons from the first cleantech wave
"This boot camp is a giant stride forward in the clean energy race - the nuclear industry can and is doing what it takes to change how things are so that we, as a planet, can have clean, affordable energy for everyone."
On founding the Nuclear Innovation Bootcamp

The Path That Got Here

2002
Enrolled at Penn State on a women-in-science scholarship - discovered nuclear engineering by accident, stayed by choice. Became a licensed nuclear reactor operator.
2006-2011
PhD at University of Wisconsin-Madison in nuclear engineering and engineering physics. Research in numerical methods for neutron transport on supercomputers. Certificate in Energy Analysis and Policy.
~2011-2019
Tenured Associate Professor of Nuclear Engineering, UC Berkeley. Eight years, leadership in data science and entrepreneurship programs.
2016
Founded the Nuclear Innovation Bootcamp at UC Berkeley - now an annual event helping nuclear researchers learn to build companies.
~2017-2020
Division Director at Lawrence Berkeley National Laboratory - ran the Cyclotron Road translational research accelerator.
~2019-2021
Program Director at U.S. DOE ARPA-E. Created MEITNER, LISA, and GEMINA nuclear fission programs. Managed agriculture (TERRA, ROOTS), solar, and VR portfolios. Helped fund 30+ companies.
2020
Co-founded the Good Energy Collective - a nuclear energy policy research organization. Serves as Board Chair.
2021
Served on Biden-Harris DOE Agency Review Team. Member of Nuclear Energy Advisory Committee (NEAC).
2022
Joined DCVC as Principal, focused on climate, sustainability, and energy. Left tenured professorship at UC Berkeley.
2023
Promoted to Partner at DCVC. DCVC launched its first dedicated climate fund. Joined boards of Fourth Power and Equilibrium Energy.
2024
Promoted to General Partner at DCVC. Joined Fervo Energy board (People & Culture Committee Chair). Joined Radiant Industries board following $300M+ Series D. Serving on SCSP Fusion Commission.

Built on First Principles

Bachelor's Degree
B.S. Nuclear Engineering
Pennsylvania State University
Licensed nuclear reactor operator during studies
Master's Degree
M.S. Nuclear Engineering & Engineering Physics
University of Wisconsin-Madison
Research in numerical methods for neutron transport
Doctoral Degree
Ph.D. Nuclear Engineering & Engineering Physics + Certificate in Energy Analysis & Policy
University of Wisconsin-Madison
Dissertation: computational methods for reactor simulation on supercomputers