X-energy Executive and Leadership Team

May, 2026

Leadership Overview

X-energy has 9 executives leading key functions including strategy, finance, technology, and operations.

Driven by innovation, X-energy is redefining nuclear energy by manufacturing advanced fuel and designing clean, reliable power plants that offer carbon-free baseload energy safely and affordably.

Leadership Roles at X-energy

  • Chief Executive Officer - Leo Sørensen
  • Chief Financial Officer - Daniel Gross
  • Senior Vice President, Chief Financial Officer - Mark Mize
  • President - Michael Slewidge
  • President, TRISO-X - Joel Duling
  • Engineering Chief of Staff - Mallory Waggoner
  • Chief Information Officer & Vice President - Matt Welsh
  • Chief Technology Officer & Senior VP - Martin van Staden
  • Executive VP & Chief of Global Operations - Dragan Popovic
  • Leo Sørensen - Chief Executive Officer

    Leo Sørensen, the Chief Executive Officer at X-energy, directs the company's overarching strategy and vision for redefining nuclear energy. Sørensen guides the development and deployment of X-energy's proprietary fuel technology, which features a unique protective coating making meltdowns impossible and retaining uranium fuel indefinitely. This leadership role involves steering the design of advanced nuclear plants that unlock the fuel's energy potential, ensuring the production of clean, carbon-free baseload power. Sørensen's focus extends to making this energy source as safe and affordable as wind or solar, available anywhere, at any time. The Chief Executive Officer ensures alignment across all departments, driving innovation and operational excellence to achieve X-energy's mission of providing reliable, next-generation nuclear solutions. Leo Sørensen's strategic direction is paramount to establishing X-energy as a global leader in safe and sustainable nuclear power generation.

    Daniel Gross - Chief Financial Officer

    Daniel Gross, the Chief Financial Officer at X-energy, oversees all financial operations and strategic financial planning. Gross manages the company's fiscal health, ensuring robust financial controls and driving sustainable growth. This role involves securing capital, managing investments, and optimizing financial performance to support X-energy's ambitious goals in redefining nuclear energy. The Chief Financial Officer works closely with other executives to align financial strategies with the company's mission of producing safe, affordable, and carbon-free baseload power. Daniel Gross's expertise is critical in navigating the financial landscape of advanced energy technologies, supporting the manufacturing of unique fuel designs and the development of innovative plant designs. Gross ensures financial transparency and accountability across all global operations, positioning X-energy for long-term success and market leadership in the clean energy sector.
    Daniel Gross

    Mark Mize - Senior Vice President, Chief Financial Officer

    Mark Mize, the Senior Vice President, Chief Financial Officer at X-energy, collaborates with the Chief Financial Officer to manage the company's financial strategy and operations. Mize supports the fiscal integrity and growth objectives of X-energy, focusing on financial planning, analysis, and reporting. This role involves contributing to capital allocation decisions and ensuring financial compliance across all business units. The Senior Vice President, Chief Financial Officer works to optimize financial resources, supporting the development of advanced nuclear fuel and plant technologies that deliver clean, carbon-free baseload power. Mark Mize's contributions are essential in maintaining financial discipline and driving the economic viability of X-energy's innovative energy solutions. Mize assists in securing the necessary funding to advance the company's mission of providing safe, affordable, and reliable nuclear energy worldwide.

    Michael Slewidge - President

    Michael Slewidge, the President at X-energy, holds a significant leadership position driving the company's strategic initiatives and operational execution. Slewidge focuses on advancing X-energy's mission to redefine nuclear energy through innovative fuel manufacturing and plant design. This role involves overseeing key business functions and ensuring the effective implementation of strategies aimed at delivering safe, affordable, and carbon-free baseload power. The President works to foster a culture of excellence and innovation, supporting the development of technologies that provide reliable energy solutions globally. Michael Slewidge's leadership is crucial in navigating the complexities of the energy market and positioning X-energy for sustained growth and impact. Slewidge ensures that operational activities align with the company's commitment to safety, sustainability, and technological advancement in the nuclear sector.

    Joel Duling - President, TRISO-X

    Joel Duling, the President, TRISO-X at X-energy, leads the specialized division focused on the manufacturing and commercialization of TRISO-X fuel. Duling directs the strategic development and operational execution for this advanced nuclear fuel, which features a unique protective coating ensuring unparalleled safety and meltdown prevention. This role is critical in scaling production to meet the growing demand for clean, carbon-free baseload power. The President, TRISO-X oversees all aspects of the fuel's lifecycle, from production to deployment, ensuring it meets rigorous safety and performance standards. Joel Duling's leadership is vital in positioning TRISO-X as a leading solution for safe, affordable, and reliable nuclear energy. Duling drives innovation within the division, supporting X-energy's broader mission to provide sustainable energy worldwide and advance the nuclear industry.
    Joel Duling

    Mallory Waggoner - Engineering Chief of Staff

    Mallory Waggoner, the Engineering Chief of Staff at X-energy, provides critical support and strategic alignment for the engineering division. Waggoner facilitates the seamless execution of engineering projects, ensuring that the design and development of X-energy's advanced nuclear fuel and plant technologies meet the highest standards of safety and efficiency. This position involves coordinating efforts across various engineering teams, optimizing workflows, and driving process improvements to accelerate innovation. The Engineering Chief of Staff acts as a key liaison, connecting engineering initiatives with the company's broader objectives of delivering reliable, carbon-free baseload power. Mallory Waggoner's role is essential in translating complex engineering concepts into actionable plans, supporting the creation of meltdown-proof fuel and clean energy generation systems. Waggoner ensures engineering operations are aligned with X-energy's mission to provide safe, affordable, and sustainable nuclear power solutions globally.

    Matt Welsh - Chief Information Officer & Vice President

    Matt Welsh, the Chief Information Officer & Vice President at X-energy, directs the company's information technology strategy and infrastructure. Welsh ensures that robust, secure, and scalable IT systems support X-energy's operations, from fuel manufacturing to plant design and global deployment. This leadership position involves overseeing all aspects of digital transformation, cybersecurity, and data management, enabling the efficient and safe production of carbon-free baseload power. The Chief Information Officer & Vice President plays a crucial role in integrating advanced technologies to enhance operational efficiency and support the company's mission of providing affordable and reliable nuclear energy solutions. Matt Welsh's strategic oversight of IT infrastructure is vital for maintaining the integrity of proprietary designs and operational data, ensuring X-energy's competitive edge. Welsh drives technological advancements that underpin the company's commitment to safety and innovation in the nuclear energy sector.
    Matt Welsh

    Martin van Staden - Chief Technology Officer & Senior VP

    Martin van Staden, the Chief Technology Officer & Senior VP at X-energy, spearheads the technological innovation and development of the company's core energy solutions. Van Staden leads the research and engineering efforts focused on X-energy's unique fuel manufacturing process, which creates meltdown-proof uranium particles, and the design of advanced nuclear plants. This critical role involves driving the technological roadmap to ensure the production of clean, carbon-free baseload power that is both safe and affordable. The Chief Technology Officer & Senior VP collaborates with global teams to advance the capabilities of nuclear energy, making it a viable and sustainable power source. Martin van Staden's technical leadership is instrumental in realizing X-energy's vision of providing reliable, next-generation nuclear power anywhere, at any time. Van Staden ensures that technological advancements align with the company's commitment to safety, efficiency, and environmental responsibility.
    Martin van Staden

    Dragan Popovic - Executive VP & Chief of Global Operations

    Dragan Popovic, the Executive VP & Chief of Global Operations at X-energy, directs the company's worldwide operational activities and strategic expansion. Popovic oversees the implementation of X-energy's advanced nuclear fuel manufacturing processes and plant designs across international markets, ensuring adherence to the highest safety and quality standards. This leadership role is pivotal in scaling operations to deliver reliable, carbon-free baseload power globally. The Executive VP & Chief of Global Operations manages supply chains, logistics, and site operations, driving efficiency and cost-effectiveness. Dragan Popovic's expertise is essential in establishing X-energy's presence in diverse regions, making safe and affordable nuclear energy accessible anywhere. Popovic ensures operational excellence supports the company's mission to provide sustainable energy solutions and solidify its position as a leader in the global nuclear industry.

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    Frequently Asked Questions Regarding X-energy Top Executives and Leadership Team

    Who leads X-energy?
    X-energy is led by Leo Sørensen (Chief Executive Officer), along with executives such as Daniel Gross (Chief Financial Officer) and Mark Mize (Senior Vice President, Chief Financial Officer).
    Who is part of X-energy’s executive team?
    The executive team of X-energy includes leaders such as Leo Sørensen (Chief Executive Officer), Daniel Gross (Chief Financial Officer), Mark Mize (Senior Vice President, Chief Financial Officer) and other senior executives.
    How many executives does X-energy have?
    X-energy has 9 executives leading key business areas.
    What roles are included in X-energy’s leadership team?
    The leadership team of X-energy includes roles such as Chief Executive Officer, Chief Financial Officer, Senior Vice President, Chief Financial Officer, President, President, TRISO-X.