Podcast
PhysicsEpisode 14

Harnessing the Sun — Fusion Energy's Promise.

With Søren Bang Korsholm, Senior Scientist, Department of Physics, DTU

Used Scientific Principles:ScaleFeedback
Applied Technology:Energy

34 min · May 13, 2025

Show Notes

About This Episode

Fusion energy is the fundamental force that powers every star in the universe. For the last 100 years, physicists have been chasing a practical answer to an audacious question: can we replicate what the sun does naturally and harness it as a human energy source? This episode explores the science of fusion from first principles, walking through the mechanism that converts mass into energy, the engineering challenges of recreating stellar conditions on Earth, and the surprising breakthrough that brings commercial fusion within reach of the next decade.

Søren Bang Korsholm brings clarity to fusion concepts that often seem impossibly abstract. The conversation moves from E=MC² and why it matters, through the elegant symmetry of stellar nucleosynthesis, to the two competing approaches humanity is using to make fusion practical. You'll come away with a working mental model of how fusion functions at the quantum level, why temperature matters so much more than we might expect, and why the achievement of fusion ignition in 2022 was genuinely historic.

This is Part 1 of a two-part exploration. A follow-up episode will examine the practical applications and integration pathways for fusion into modern electrical grids.

In This Episode

Key Quotes

"If you have a pool you could put here under the table and five old laptop batteries, that could supply a European with energy for a lifetime."

"If you talk about the energy to master fuel and you compare to coal, which is our main energy supply in the world right now, it's a factor of 10 million."

"Every second, 600 million tons of hydrogen is transformed into 596 million tons of helium. So you're losing four million tons a second on the sun."

"The sun is not that hot. We are making hotter plasmas."

About Søren Bang Korsholm

Søren Bang Korsholm is a Senior Scientist at the Department of Physics at DTU (Technical University of Denmark). His research focuses on fusion plasma physics and the engineering challenges of magnetic confinement. He brings both theoretical rigour and practical knowledge from working on some of Europe's most advanced fusion experiments.

Resources Mentioned

Contact & Follow

Email: podcast@bigideasonly.com

Website: montanus.co/bigideasonly

More

More from this episode.

Physics

Why Fusion's Greatest Achievement Isn't the Physics

Fusion's greatest achievement is not the plasma temperature or the confinement geometry. It is seventy years of open, international collaboration across the Cold War divide — and what that model reveals about how civilisation-scale problems actually get solved.

4 min read · May 13, 2025

Physics

Why Fusion Energy is the Universe's Greatest Teacher

The sun has been running a fusion experiment for four billion years on the same fuel. Søren Bang Korsholm explains the physics, the engineering challenge of confinement, why fusion cannot run away like fission, and what the history of international collaboration reveals about how large problems actually get solved.

8 min read · May 13, 2025