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Calyos is a leading expert in advanced heat pipe technologies

Advanced technologies include; loop heat pipes, pulsating heat pipes and micro-channel heat pipes. Our team makes applying these advanced technologies viable and feasible.

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Sustainable Cooling For Your Industry

Thermal management is a critical requirement across many different market sectors.

Did you know?
12x more EVs are expected to be sold in 2030 vs 2020
This will drive the increased use of power electronics and battery systems. Cooling is critical for power efficiency and lifetime in both applications.


Electrification is transforming the industry and is resulting in new vehicle architectures, from battery electric to hydrogen fuel cells. Regulating the temperature of components and systems with high-performance thermal management solutions is critical in extending the lifetime of a vehicle. Calyos provides solutions in all of these sectors:

  • Motorsport
  • Light Electric Vehicles
  • Commercial Vehicles
  • Off-Highway Vehicles
  • Aviation & Aeronautics
  • Rail
  • Marine


Power Electronics


Embedded Electronics

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As the power consumption of processors continues to increase so is the need to evacuate the waste heat. Regulating the temperature of components and systems with high-performance thermal management solutions is critical to ensure components stay within safe operating temperatures. Calyos provides solutions in all of these sectors:

  • Silicon Providers
  • Server Suppliers
  • Data Center Operators
  • Data Center Integrators
  • Telco Equipment
  • Specialist Computers




Embedded Computing

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Did you know?
11x more data is estimated to be processed in 2030 vs 2020
This will drive the increased use of all kinds of different processors. Cooling is critical to maximize the components processing speed and efficiency.

Two-Phase Technologies

Our team consists of experts in all things two-phase, who design and produce cooling systems using the following technologies.

Heat Pipes

Traditional HPs are beautifully simple and provide incredibly low thermal resistances.

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Loop Heat Pipes

LHPs provide the ability to not only handle very high heat flux, but also the ability to transport heat long distances.

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Pulsating Heat Pipes

PHPs are new technology with great potential and Calyos is working hard to mature it for a range of applications.

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Micro Channel Heat Pipes

MCHPs are a hybrid HP-PHP solution that remains a simple and lightweight ultra-efficient cooling solution.

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General Comparison

Ever increasing thermal requirements are forcing engineers to consider new technologies. Advanced heat pipes are the only solution that is capable of handling higher performance demands without sacrificing on lifetime, maintenance and safety.



Use & TCO



High power components

Low thermal resistance

>10 year lifetime


No safety or fire risk

No risk of short-circuits

Passive transport of heat

Heat recovery capability

Heat Pipes

Calyos is a leading expert in two-phase heat transfer technologies

In 2014 Calyos set about achieving our mission to provide sustainable, passive, two-phase cooling solutions. Calyos is a spin-off from Euro Heat Pipes (EHP), who successfully developed similar two-phase technologies for the space industry. Initially our research and development focused on adapting the technologies for earth applications, including moving to a flat evaporator and utilising a dielectric working fluid. Calyos now produces solutions primarily targeted at batteries, power electronics and processor cooling.

Why Two-Phase?

Calyos believes in two-phase cooling because this technology brings a clear set of benefits to our customers

No Water

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Calyos specializes in using a dielectric, green refrigerant, removing the risk of short-circuits in the event of damage.

No Maintenance

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Our products are helium tested for tightness before they leave our factory, ensuring long lifetimes and zero maintenance.

100% Passive

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All of our two-phase technologies harness the waste heat to vaporize a fluid, using the problem to power the solution.

No Pumps

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By being 100% passive and having no pumps it removes the most common point of failure in liquid cooling systems.

High Performance

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Vaporizing a fluid is an incredibly efficient and results in systems with extremely low thermal resistances.

Why Calyos?

We make applying these advanced heat pipe technologies feasible

Capillary Pump

We produce the best wick structures that provide the maximum pumping capacity (and therefore performance).

Simulation Capabilities

Built from real-world data we have created accurate in-house models. Plus we use standard software where possible.

Fluid Selection

Typically we use R1233zd(E), a low GWP (<1), dielectric, non-toxic and non-flammable refrigerant. Other fluids are available.

Manufacturing Facilities

Built for small series production and prototyping it allows us to work efficiently and react quickly as it is side by side with our design team.

Design & Integration

Experts in adapting the solutions to your application, without which the value of two-phase cooling cannot be delivered.

Testing Laboratory

Calyos’ dedicated test engineers can provide advanced thermal testing of prototypes and solutions, replicating real-world scenarios.



heat pipe for power electronics


Ideal for static applications such as charging infrastructure, our unique heat pipe solution is a little different from traditional heat pipes. Thanks to our expertise in two-phase technologies we are able to use our grooved wick structure in combination with a unique mechanical design to provide the best cost to performance ratio.

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loop heat pipe for power electronics


Utilizing our flagship technology, our solution offers the only passive alternative to direct water cooling. It is ready for the latest, high-heat density (GaN & SiC) components and can be deployed either by combining with, or by replacing an existing cooling system. Our solution provides an ultra-reliable, maintenance free, long-lifetime power electronics cooling solution.

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loop heat pipe for embedded electronics


This is the most flexible solution for cooling embedded electronics on the market. Ultra reliable and maintenance free, our solution is ideal for even the most harsh environments. The system is able to access any remote cold source no matter the size or type.

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loop heat pipe for data center servers


Our trusted flagship technology has long been deployed in server environments and more recently we have expanded into the telecommunications market. Calyos utilises standard components to build a solution specific to your mechanical design, with our inherent fit-and-forget reliability.

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loop heat pipe for data center racks


Calyos aims to accelerate the sustainable transition of data centers from air cooling to full liquid cooling, notably enabling heat recovery capabilities. The inevitable next step for our product development is to transition our technology from single server to full rack cooling.

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micro channel heat pipe for batteries


Placed in between cells, these tiny heat pipes can assist in both warming and cooling cells. The cross sectional shape can be completely customised and these solutions are incredibly cost effective to mass produce. Using a dielectric refrigerant inside removes the risk of short circuits, maintaining Calyos' fit-and-forget reliability.

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Why is thermal management important?

Thermal challenges used to be resolved easily with a simple, solid heat sink. Fast forward to today and we have exhausted the design possibilities of traditional heat sinks. As electronic technology reduces in size it increases in heat density requiring more and more powerful thermal systems to dissipate this heat. With the rapid and continuing rise of electrification and data processing, thermal management of electronics faces rapid demands. In combination with the demand for sustainable, environmentally friendly solutions Calyos is in a unique position offering 100% passive thermal solutions in a market of pumped liquid cooling.

component reliabiltiy

Thermal management is the most critical reliability factor for electronic components. A good thermal system extends the lifetime and increases the performance of both processors and power electronics.

minimize charging times

Both power electronics and battery cooling are critical to the speed and efficiency of a vehicles charging time. Cooling affects both components inside the vehicle and the charging infrastructure itself.

waste heat recovery

Waste heat from data centers is typically released into the ambient air. Heat recovery provides the opportunity to heat greenhouses or residential buildings, reducing the data centers environmental impact.

Maximize EV range

Typically EVs use up precious energy to power their cooling systems. Switching to passive cooling can save this power for the e-motor increasing the range of any type of hybrid or full electric vehicle.


Latest News


Calyos' LHP Technology Triumphs in Automotive Proving Ground Tests

November 20, 2023

In a significant milestone, Calyos Loop Heat Pipes demonstrate proven performance under varied automotive test conditions.

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Calyos to pariticapte in ESA Commercialisation Days

November 1, 2023

On November 27th Calyos will be presenting an elevator pitch at the ESA Commercialisation Days: Transportation event.

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Calyos wins CLEPA Innovation Award

October 20, 2023

Calyos emerged as the winner fo the Top Innovator 'Green' award for SME's.

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Let's Get Started

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