Julien Barber is an investor at Emerson Collective, a venture and policy firm founded by Laurene Powell Jobs, where he backs bold bets on decarbonization, infrastructure, and long-horizon climate technologies. Before becoming an investor, Julien researched fusion energy at MIT and co-founded a carbon-tech startup.

In today’s episode, we go deep into Julien’s investing philosophy, Emerson’s unique model, and the hard tech categories he believes are most undercapitalized.

We cover:

Why Emerson is structured for risk others can’t take
Fusion, fission, and the evolving energy stack
AI’s impact on power demand and hardware acceleration
How to invest when the grid is the bottleneck
Building conviction in hard tech when capital is scarce
Public vs. private roles in scaling fusion
What a 7-million-fold increase in energy density may actually look like

• Chapters •
00:00 – Intro

01:49 – From scientist to investor

04:37 – Why Julien chose fusion

08:57 – Investment process at Emerson

10:08 – The team at Emerson

12:15 – Is Emerson consensus-driven and why is it an LLC?

14:07 – Under-invested areas in climate & industrial tech

17:24 – Are AI valuations reasonable today?

18:59 – Bottlenecks in the grid

23:11 – AI energy consumption: hype or real concern?

27:10 – Bridging the energy gap

29:20 – Fusion’s role in the next decade

31:24 – Google & Commonwealth Fusion: serious commercial signal?

32:37 – Are we underinvesting in fusion?

39:12 – Who will reach commercial fusion first?

41:36 – 30-year future if fusion succeeds

• Show notes •

Emerson’s socials — https://x.com/emcollective

Emerson’s website — https://www.emersoncollective.com/

Mo's socials — https://twitter.com/itsmoislam

Payload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspace

Ignition’s socials — https://twitter.com/ignitionnuclear /

https://www.linkedin.com/company/ignition-nuclear/

Tectonic’s socials — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/

Valley of Depth archive — Listen: https://pod.payloadspace.com/

• About us •

Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.

The Energy Grail, with Julien Barber (Investor at Emerson Collective)

Valley of Depth