Cooling becomes strategic: Calyos brings passive thermal tech to Europe’s defence stack

2026-04-15 · Source: Tech.eu - Tech.eu · Field: Technology & Digital — Emerging Technologies & Innovation, Cloud Computing & IT Infrastructure, Robotics & Autonomous Systems · Depth: Intermediate, medium

Summary

Belgian startup Calyos is advancing fully passive, two-phase cooling systems manufactured entirely in Europe, targeting data centers, mobility, and defense applications. The technology, which originated from satellite engineering, leverages a fluid's phase change to transfer heat without pumps or moving parts, offering high reliability, silence, and efficiency. Calyos's solution was selected by NATO DIANA to enhance energy efficiency and resilience in data center environments, and it is designed for supply chain resilience as it relies primarily on metal components manufacturable within Europe. The company is applying its technology to cool batteries, processors, and power electronics in e-mobility (e.g., motorsport, e-bikes), computing, and defence, collaborating with partners like Airbus and a German automotive manufacturer. Integration typically takes about 18 months, with scaling accelerating thereafter.

Key takeaway

For CTOs and VPs of Engineering evaluating thermal management solutions for critical infrastructure or defense applications, Calyos's European-made, passive two-phase cooling technology offers a compelling path to enhanced reliability, energy efficiency, and supply chain sovereignty. You should explore this technology to reduce reliance on active cooling systems and external supply chains, particularly for deployable or harsh-environment compute platforms and e-mobility systems.

Key insights

Passive two-phase cooling offers reliable, efficient thermal management for demanding applications like defense and e-mobility.

Principles

• Passive cooling enhances system reliability.
• European manufacturing strengthens supply chain sovereignty.

Method

Two-phase cooling absorbs heat by fluid evaporation, transports vapor, releases heat via condensation, and returns liquid via capillary action, all without mechanical pumps.

In practice

• Integrate two-phase cooling for harsh environment electronics.
• Utilize passive thermal management for battery longevity.
• Seek expert advice for defense market entry.

Topics

• Two-phase Cooling
• Passive Thermal Management
• NATO DIANA Program
• Technological Sovereignty
• Defence Applications

Best for: CTO, VP of Engineering/Data, Executive, AI Hardware Engineer, Director of AI/ML, Entrepreneur

Related on AIssential

• Liquid-cooled AI systems expose the limits of traditional storage architecture — Hybrid air/liquid cooling for AI infrastructure is inefficient and creates thermal liabilities for storage.
• Space-Station Tech Pivots to Cool AI Data Centers — Space-station derived liquid cooling and carbon nanotube TIMs are critical for managing extreme heat in next-gen AI data centers.
• The Hidden Water Cost of Every Prompt — Water consumption for data center cooling is emerging as a critical environmental limit for AI.
• Salute & MCIM: Cutting Liquid Cooling Risk In AI DCs — Integrating operational intelligence with direct-to-chip liquid cooling services enhances high-density AI/HPC data center management.
• Israeli AI cooling startup ZutaCore raises $100 million Series C at estimated $600 million valuation - CTech — ZutaCore's HyperCool offers a waterless, two-phase direct-to-chip liquid cooling solution for high-density AI data centers.
• How This Nuclear Reactor Prevents Meltdowns — This reactor design uses passive gravity-fed fuel drainage to prevent meltdowns upon power loss.

Open in AIssential →

Editorial summary, takeaway, and curation by AIssential. Original article published by Tech.eu - Tech.eu.