Custom Thermal & Sensor Solutions for NPPs

THERMOCOAX is a leading partner in sensors, cabling, and heating solutions for next-generation CO2-free nuclear power plants. 

With more than 40 60 years in the business, our dedicated nuclear engineering team is a household name in the design of cutting-edge thermal and sensing solutions for nuclear installations around the world. From fuel production to reprocessing to design and manufacture of components, we provide custom sensors, heaters and cabling for every stage of the nuclear cycle. 

Our commitment to safety in this sector is witnessed by our 100% traceability guarantee along the supply chain, our expertise in construction codes, and certification in line with the highest nuclear quality standards. 

Nuclear Partners around the World  

THERMOCOAX sensors and heating elements are already used in a variety of fission reactors, including PWR, BWR, liquid metal and gas-cooled. Our partners are located in Europe, China, Korea, USA, India and South Africa, among others. 

Project collaborations include the JET Tokamak fusion reactor in the UK and the LASER Mega Joule in France. THERMOCOAX is also an active participant in the ITER program and provides custom thermal products for in-core and ex-core reactor solutions in Generation IV reactors. 

Bespoke solutions for optimal safety 

Cabling systems 

THERMOCOAX uses its proprietary mineral insulated cable technology to develop state-of-the-art cabling systems for NPPs. Our accident-proof MI cable assemblies are still operating when exposed to extremes of radiation and the connectors are classified for severe accident in reactor containment.  

Based on our TWISTCOAX® technology, our twisted MI cables are the ideal solution for fusion reactors because they are impervious to high magnetic field fluctuations. 


The proprietary THERMOCOAX nuclear manufacturing processes push the limits of performance and long-term reliability of heaters for nuclear use. Our high-watt density pressuriser heaters have an extended service life compared to other technologies.  

For the nuclear research market we supply fuel pin simulators that reproduce the very high flux of fuel pins by electrical heating. This enables engineers to study the behaviour of cladding material or the heat exchange with the primary coolant. 


Radiation sensors 

THERMOCOAX NUCLEAR division has been providing Self-Powered Neutron Detectors (SPND) to research reactors and nuclear fission power plants since the 1970s. Our modular real-time SPND offer a cost-effective and efficient solution for neutron flux monitoring, and thus the safe operation of NPPs. They are licensed for use in Gen IV reactors. 

We also supply Self-Powered Gamma Detectors (SPGD), which are based on a simple working principle. This innovative sensor has been patented by CEA and provides an impressive performance in reactor pool conditions.  

Temperature sensors 

One of the key parameters in real-time reactor power calculation is the core outlet temperature. Our in-core thermocouples monitor this temperature and, in the event of fluctuations, they prevent the nucleate from boiling at the cladding of fuel assemblies. These two critical functions require the highest reliability and quality standards.  

The temperature of containment is a key factor in reactor monitoring. Our certified Resistance Temperature Detectors (RTD) ensure a very short reaction time and are built to last for decades.   

Level sensors 

In nuclear waste management, when conditions do not allow for the use of standard technologies, a robust design and construction is required. THERMOCOAX has stepped up to the plate with its Spent Fuel Pool Level Measurement (SFPLM) sensors, ensuring the critical monitoring of water levels in case of water boil-off. This solution meets the highest industry standards required by our clients. 

Four decades of integrity 

THERMOCOAX has been a respected partner of the nuclear industry for the last fifty sixty years. At every step of the cycle, from research reactors and NPPs, nuclear fuel production, and spent fuel reprocessing and waste management, we adhere to the highest nuclear quality standards.  

Our excellence in providing custom solutions and proprietary manufacturing processes means we are able to satisfy the demanding needs of our clients, again and again. 

For further details, please don’t hesitate to visit our Nuclear pages.