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Climate/Energy

Radiant

Portable nuclear microreactors for clean energy

London· 16 rolesGloucestershire· 4 rolesUK· 2 roles

CORE INFO

$300M
Total Funding
Series D+
Round
2019
Founded
44
Team Size
El Segundo, California, United States
Headquarters

Radiant develops portable nuclear microreactors designed to replace diesel generators, providing clean and reliable energy for remote communities, emergency response, and military installations.

  • Radiant raised over $300 million in a Series D funding round led by Draper Associates and Boost VC, reaching a valuation of over $1.8 billion.techcrunch.com
  • TechCrunch reported on Radiant's significant funding and its plans to develop a portable 1 MW nuclear reactor.techcrunch.com
  • Radiant signed an agreement with data center developer Equinix to supply 20 of its reactors.techcrunch.com

WHY WE WOULD WORK AT RADIANT

Innovative Clean Energy Solutions

Join a pioneering team developing the Kaleidos microreactor, a portable nuclear solution designed to replace diesel generators and provide resilient power for critical applications.

Mission-Driven Culture

Be part of a mission to deliver clean, reliable energy to remote communities and emergency responders, making a tangible impact on global energy challenges.

Rapid Growth Opportunities

With over $300 million raised in Series D funding, Radiant is poised for significant expansion, offering employees the chance to grow alongside the company.

Collaborative Team Environment

Work with a diverse team of 44 passionate individuals, including experts from top tech backgrounds, fostering a culture of innovation and collaboration.

Cutting-Edge Technology

Utilize advanced TRISO fuel technology in the Kaleidos reactor, ensuring safety and efficiency while pushing the boundaries of nuclear energy.

Global Impact

Contribute to projects that support military installations and data centers, helping to reshape the future of energy across various critical sectors.

MARKET AND TRACTION

TOTAL ADDRESSABLE MARKET

  • Radiant's microreactors target industries requiring reliable, portable power solutions, including remote communities, emergency response operations, military installations, and data centers.

  • The demand for clean energy solutions is growing globally, particularly in areas lacking stable electricity infrastructure, presenting a significant market opportunity for Radiant's technology.
  • NOTABLE CUSTOMERS

  • In August 2025, Radiant signed an agreement with data center developer Equinix to supply 20 of its reactors, marking a significant step in its customer acquisition strategy.

  • The partnership with Equinix highlights Radiant's potential to serve critical infrastructure sectors that require dependable energy sources.
  • KEY METRICS

    ✦ KEY METRIC
  • Radiant has raised a total of over $300 million in its Series D funding round, achieving a post-money valuation of over $1.8 billion.

  • The company has a team size of 44 employees as of December 31, 2023, indicating a focused and specialized workforce to drive its innovative projects.
  • GROWTH TACTICS

  • Radiant plans to test its first reactor in 2026, with initial customer deployments expected to begin in 2028, demonstrating a clear roadmap for product rollout.

  • The company is also investing in building its first factory, R-50, in Oak Ridge, Tennessee, which is projected to create up to 175 jobs and enhance production capabilities.
  • COMPETITIVE ADVANTAGE

  • The Kaleidos microreactor is unique in its transportability via truck or aircraft and its ability to operate without on-site water for cooling, setting it apart from traditional nuclear solutions.

  • Utilizing meltdown-proof TRISO fuel and helium gas for cooling significantly reduces the risk of radioactive leaks, enhancing safety and reliability compared to conventional reactors.
  • PRODUCT AND TECH

    Kaleidos Microreactor

    Radiant's flagship product, the Kaleidos microreactor, is a portable 1-megawatt nuclear reactor designed to replace diesel generators, providing reliable power for remote locations and critical applications.

    TRISO Fuel Technology

    The Kaleidos microreactor utilizes TRISO fuel, which consists of uranium kernels encased in layers of carbon and silicon carbide, enhancing safety and preventing meltdowns.

    Helium Cooling System

    This microreactor operates using helium gas for cooling, eliminating the need for on-site water and significantly reducing the risk of radioactive leaks.

    Five-Year Operating Cycle

    The Kaleidos microreactor is designed for a five-year operating cycle between refueling, ensuring long-term reliability and minimal maintenance for users.

    Portable Power Solutions

    Radiant focuses on providing portable energy solutions that can be easily transported via truck or aircraft, making them ideal for emergency response, military installations, and remote communities.

    COMPANY CULTURE

    Values

  • Commitment to clean energy solutions

  • Innovation in nuclear technology

  • Safety and reliability in power generation

  • Support for remote and underserved communities

  • Environmental sustainability through reduced emissions
  • Operating Principles

  • Focus on portable and mass-produced energy solutions

  • Emphasis on safety with meltdown-proof technology

  • Continuous improvement through R&D

  • Collaboration with industry partners for deployment

  • Agile response to market needs and customer feedback
  • Benefits

  • Providing resilient power for critical applications

  • Reducing reliance on fossil fuels

  • Enhancing energy access in remote areas

  • Supporting emergency response operations

  • Contributing to military energy independence
  • Team Cadence

  • Regular team meetings to foster collaboration

  • Agile project management practices

  • Open communication channels across all levels

  • Emphasis on cross-functional teamwork

  • Monthly all-hands meetings to share updates and achievements
  • Learning & Growth

  • Opportunities for professional development and training

  • Encouragement of innovative thinking and problem-solving

  • Access to industry conferences and workshops

  • Mentorship programs for new employees

  • Support for continuous learning in nuclear technology
  • HIRING SIGNAL

    23
    Open roles on their careers page
    Snapshot via live ATS poll
    —
    Net new roles in the last 90 days
    Available once weekly history accrues
    90-Day VelocityV2 · BACKFILL
    Trend builds weekly as historical rows accrue
    By Function
    Breakdown of open roles
    Other · 1
    G&A · 4
    Product · 2
    Support · 1
    Marketing · 1
    Operations · 6
    Engineering · 8
    Top Locations
    Where hiring is concentrated
    Remote-eligible postings counted separately
    London
    16
    Gloucestershire
    4
    UK
    2
    Gloucester
    1
    SourcesGreenhouseLeverAshbyWorkableSmartRecruitersRipplingRecruiteeFallback · Wellfound, YC Work-at-a-Startup, careers-page scrape

    KEY COMPANY ANNOUNCEMENTS

    Filter
    12 announcements · ranked by importance
    Aug 26, 2026CUSTOMER WINRadiant Wins $750M Contract from US Army to Deliver Energy Independence to US Military Basesradiantnuclear.com
    Apr 22, 2026CUSTOMER WINAir Force Selects Radiant to Deliver Microreactors to Buckley Space Force Baseradiantnuclear.com
    Feb 26, 2026FUNDINGAdam Draper leads Radiant Nuclear's $360M round after backing every round from pre-seed | TBPN Digesttbpndigest.com
    Dec 17, 2025PRESSRadiant Nuclear raises $300M for its semi-sized 1 MW reactor | TechCrunchtechcrunch.com
    Jul 2, 2025MILESTONERadiant Selected by Department of Energy as First New Nuclear Reactor Design to Be Tested in DOMEradiantnuclear.com
    May 28, 2025FUNDINGRadiant closes $165 Million Series C with additional funding from Giant Ventures, StepStone, ARK Venture Fund, and others - Radiant Nuclearradiantnuclear.com
    Jan 1, 2023FOUNDER PROFILERadiant - Not Boring by Packy McCormicknotboring.co
    Jan 18, 2023ESSAYWhy I Started Radiant - Radiant Nuclearradiantnuclear.com
    May 31, 2024INTERVIEWRadiant CEO Doug Bernauer on Portable Nuclear Microreactors & the Future of Clean Energypodcasts.apple.com
    Apr 24, 2023FUNDINGRadiant Series Bradiantnuclear.com
    Mar 1, 2022FUNDINGRadiantusv.com
    Jun 3, 2025EXEC HIRERita Baranwal Joins Radiant as Chief Nuclear Officerradiantnuclear.com