The Origin: Where Curiosity Took Flight

The Calyos story begins not with electric vehicles or servers, but with the Belgian aerospace company SABCA (Société Anonyme Belge de Constructions Aéronautiques), founded in 1920. Known primarily for manufacturing parts for aircraft, SABCA also housed a pioneering R&D division focused on space activities. This was no ordinary department, it operated with unusual freedom (more typical of the time). Engineers were trusted to explore technology independently, supported by flexible budgets and open-ended objectives.

One such engineer, often described as very driven and strong-minded, attended a pivotal seminar in the U.S. in the late 1970s or early 1980s. The speaker was Russian scientist that fled the USSR. He was a leading authority on an obscure thermal management method known as the Loop Heat Pipes (LHP). The concept intrigued the SABCA engineer, critically at a time when very few in Europe had even heard of two-phase heat transfer systems, he saw its potential and was determined to dig deeper.

First Connections, First Patents

This passion wasn’t confined to the lab. Outside of work, the engineer’s son who was active in the local scouts, was friends with another inquisitive mind: Stephan Van Oost, a young man fascinated by emerging technologies. Their friendship led Stephan to meet the father of his friend, who eventually hired him into SABCA’s R&D division.

Stephan quickly became immersed in LHP development. His contributions were profound: in 1985, he filed Belgium’s first patent for LHPs, formalizing the country’s entry into the world of advanced two-phase cooling. Around this time, the European Space Agency (ESA) also began backing SABCA's R&D efforts, recognizing the potential of passive thermal control systems for spacecraft.

From Academic Curiosity to Commercial Potential

The next chapter unfolded in the late 1990s, when Professor Jean-Claude Legros, a respected figure at the Microgravity Research Center (MRC) at ULB (Université Libre de Bruxelles), learned of the progress SABCA was making. Belgian universities were then lagging behind other countries in launching commercial spin-offs from academic research, a gap ULB’s then president was keen to close.

This led to a formal collaboration between SABCA and ULB, focused specifically on two-phase cooling technologies. Over time, SABCA sold its patents, R&D team, and expertise to ULB, creating the foundations for a new venture in 2001: Euro Heat Pipes (EHP). Legros, deeply invested in the science, became CEO, with Stephan Van Oost CTO of the newly formed company. The mission was to commercialize LHP technology for space applications.

The Need for Change

Despite strong technical leadership, EHP soon encountered growing pains. Legros was a brilliant academic, but the challenges of commercializing deep-tech solutions required different skills, particularly around market strategy, partnerships, and scale. The company began to lose money. It was time for a new direction.

The President of EHP’s Board, also the CFO of ULB, Patrick Goblet, brought in a consulting professional: Olivier de Laet. He was tasked with evaluating the situation and drafting a plan. His analysis was sharp, and his strategy compelling enough that Patrick asked him to implement it and Olivier became CEO of EHP in 2004.

Around the same time a young talented, PhD graduate from EPFL, who studied in John Thome's Laboratory was hired to work with Stephan, his name was Vincent Dupont.

The Relationship Builder

Olivier’s approach was personal and strategic. To build the business, he understood he needed more than just a product, he needed trust from the European aerospace leaders. He cultivated deep relationships with key players. namely, Airbus and Thales, getting to know their people on a personal level. “I knew the names of the CEOs partners, children, and even their pets” Olivier told me.

These efforts paid off. By 2008, Airbus acquired a 17% stake in EHP, recognizing the company as a vital supplier. However, this began to reveal tensions in strategy. Olivier envisioned growth in the United States and in non-space markets, but Airbus was interested solely in EHP’s space applications for the european market.

The Fork in the Road: Enter Calyos

As Airbus' involvement grew, eventually reaching 51% in 2016, it became clear that EHP's expansion into non-space sectors would have to happen in a separate company. Thus, Calyos was incorporated, with a mandate to transition space-grade two-phase cooling into terrestrial markets.

For a few years, Olivier juggled both EHP and Calyos. Eventually, he left EHP to focus entirely on Calyos, bringing with him a bold vision: to revolutionize cooling across sectors where heat management had become a bottleneck. A vision he still holds today.

From Tubes to Tech: A New Era of Cooling

Joining him was Vincent Dupont, who had previously left EHP for a year-long sabbatical hiking in the Pyrenees. Vincent later returned to the two-phase world as CTO of Calyos, drawn by the mission and entrepreneurial spirit of the new venture.

The challenge was significant. Adapting LHP technology from space to Earth required new fluids, different materials, and tighter cost control. Space systems are bespoke; terrestrial markets demand affordability and scalability. One of the most critical engineering shifts was the transition from tubular to flat evaporators, a change essential for applications like electronics cooling.

Scaling Success Across Industries

Calyos’ early breakthroughs came in aeronautic and rail sectors as they demanded high reliability in challenging environments. Taking from the space business, where the ability to repair is almost non-existent, the reliability of two-phase systems was very compelling. These industries became proving grounds for new designs, materials, and manufacturing techniques. From there, Calyos is expanding successfully into energy and e-mobility, carving out a leadership position in advanced thermal management.

A key pillar of our progression has been down to the unique, innovative capillary structures that we design and produce, we are yet to meet another company with such experience. However this success is not only due to our space-born passive two-phase cooling technologies but also down to the team, many of which have been with Calyos much longer than me.

What began as a niche curiosity within a Belgian aerospace firm is now becoming a global effort to redefine how heat is handled, efficiently, passively, and sustainably in mass market applications like electric vehicles and tomorrow maybe data centers.

From Space to Earth, and Beyond

Today, Calyos is not just an innovator in thermal technologies; it’s a pioneer in bridging the gap between space-grade engineering and industrial-scale impact. Through vision, persistence, and a commitment to reimagining what’s possible, Calyos is taking cooling from the stratosphere to the circuit board, and wer're only just getting started.

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