Deep Fission

We are ringing the Nasdaq Exchange Closing Bell at 4 p.m. ET today, in celebration of the arrival of our Deep Fission Gravity Nuclear Reactor™ prototype canister to our Parsons, Kansas, site and our recent listing on the Nasdaq Stock Market (FISN). 🎉

Now onsite, our prototype canister will be prepared for additional testing as our team advances permitting and preparations for our non-nuclear demonstration borehole. In parallel, we're continuing the development of our full-scale nuclear demonstration borehole and other key systems that support our commercial deployment approach.

Tune in to the ringing ➡️
https://www.nasdaq.com/marketsite/bell-ringing-ceremony

Learn more ➡️ https://www.deepfission.com/pr-media-kit/press-releases/detail/114/deep-fission-prototype-reactor-canister-arrives-at-kansas-site-advancing-reactor-proof-of-concept-program

This Independence Day, we're celebrating America’s 250th birthday and the innovation that has helped define our country from the beginning.

From the engineers, scientists, builders, and communities working to solve complex challenges, progress has always been driven by people willing to think differently and put ideas into action.

That spirit continues to inspire our work at Deep Fission as we explore an innovative approach to expand access to reliable, affordable energy through proven nuclear technology deployed one mile underground.

Happy 4th of July from the Deep Fission team! 🇺🇸

Learn more: https://www.deepfission.com/technology

Meet Steve Spears. 👋 He’s a Senior Nuclear Operations Engineer at Deep Fission helping shape our operations, maintenance, and training programs and bringing decades of experience from both the U.S. Navy and commercial nuclear power to support safe, reliable plant operations.

"What inspires me most about the work we're doing at Deep Fission is the opportunity to help apply proven nuclear technology in a simpler and more deployable way. It's exciting to be part of a team that is focused on expanding access to reliable energy while building on decades of industry experience and operational knowledge."

𝗪𝗵𝗮𝘁 𝗦𝘁𝗲𝘃𝗲 𝘄𝗶𝘀𝗵𝗲𝘀 𝗺𝗼𝗿𝗲 𝗽𝗲𝗼𝗽𝗹𝗲 𝘂𝗻𝗱𝗲𝗿𝘀𝘁𝗼𝗼𝗱 𝗮𝗯𝗼𝘂𝘁 𝗻𝘂𝗰𝗹𝗲𝗮𝗿 ⚛️

"I wish more people understood that nuclear energy is one of the safest and most reliable sources of low-carbon electricity available today. Decades of operational experience have demonstrated its ability to provide dependable power while maintaining a strong commitment to safety.

Deep Fission is building on that foundation by exploring new ways to make nuclear power more accessible, scalable, and affordable. By combining established nuclear technology with innovative deployment approaches, we're working to expand access to reliable energy while maintaining the high standards that have defined the industry for decades.

After more than 20 years in the U.S. Navy and over 15 years in commercial nuclear power, I joined Deep Fission because of the people and the vision. It's a unique opportunity to work with a talented team focused on responsible deployment, operational simplicity, and the future of reliable nuclear infrastructure."

Learn more: https://brnw.ch/21x3Nxp

Steam has powered electricity generation for more than a century. Deep Fission is aiming to apply that same proven principle in a unique environment ➡️ one mile underground.

Our advanced pressurized water reactor (PWR) is designed to use standard fuel assemblies and readily available low-enriched uranium (LEU) fuel, building on decades of operating experience with proven reactor technology.

Our approach integrates conventional geothermal engineering principles with a steam generation system designed to support efficient heat transfer while enabling passive safety features.

The desired result is a practical pathway to reliable, affordable electricity built on established technologies, engineering practices, and supply chains.

https://www.deepfission.com/technology

𝗣𝗿𝗼𝘁𝗼𝘁𝘆𝗽𝗲 𝗿𝗲𝗮𝗰𝘁𝗼𝗿 𝗰𝗮𝗻𝗶𝘀𝘁𝗲𝗿 𝘀𝘂𝗰𝗰𝗲𝘀𝘀𝗳𝘂𝗹𝗹𝘆 𝗳𝗮𝗯𝗿𝗶𝗰𝗮𝘁𝗲𝗱 𝗮𝗻𝗱 𝘁𝗲𝘀𝘁𝗲𝗱 ✅

The Deep Fission team has successfully fabricated and tested our first prototype reactor canister, achieving an important milestone on our path toward deployment. The testing confirmed that the canister meets key industry requirements for structural integrity and leak tightness.

This canister will support testing of the integrated assembly, installation, and retrieval of a full-scale reactor system within a borehole.

As we continue advancing these demonstrations, we're building the capabilities needed to validate our deployment approach to deliver reliable, affordable energy from one mile underground.

Learn more: https://deepfission.com/technology
(Nasdaq: FISN)

We are grateful to Idaho National Laboratory for hosting us yesterday, and providing the opportunity to connect with U.S. Department of Energy Secretary Chris Wright , and our fellow developers in the Reactor Pilot Program.

It’s an exciting time for nuclear energy, and Deep Fission is proud to be contributing to U.S. nuclear innovation as we advance our path toward commercialization.

Learn more: https://www.deepfission.com/about-us

U.S. Department of Energy Office of Nuclear Energy

“These are all companies that they have different ideas, but they all have an intelligence, drive and a boldness about them…..my bet is 100% success.👏

Everyone that got chosen and is in this program… I can see it the eyes, and see it in the hearts…we are going to see success across the board.”

We are honored to be among the 10 companies in the U.S. Department of Energy's Reactor Pilot Program, and feel energized from being personally recognized by Secretary Chris Wright today.

Our path to commercialization is feeling more important than ever.

Check it out: https://www.youtube.com/live/P1rIWi1slKg?si=lwCN-J0lchSLyLXJ&t=2819 (Timestamp: ~47:00)

U.S. Department of Energy Office of Nuclear Energy

Secretary Wright Celebrates President Trump's U.S. Nuclear Energy Accomplishments — June 25, 2026 Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

Today, Deep Fission is proud to be represented at Idaho National Laboratory’s Golden Era of Nuclear Power event by our Co-Founder and CEO, Liz Muller, alongside members of the Deep Fission team.

This event brings together leaders from across the nuclear energy ecosystem, including U.S. Secretary of Energy Secretary Chris Wright , to discuss how advanced reactors will help meet the world's growing demand for reliable, low-carbon energy.

Held just ahead of the United States' 250th anniversary, the event highlights the nation's accelerating nuclear renaissance and the technologies shaping America's energy future.

We're excited to be part of this important conversation and to help shape the future of nuclear energy.

Read more: https://www.deepfission.com/news-media/press-releases/detail/113/deep-fission-joins-doe-secretary-wright-at-idaho-national-laboratory-event-to-celebrate-nuclear-innovation

U.S. Department of Energy, U.S. Department of Energy Office of Nuclear Energy