sCO2-HeRo · Project

Backup Cooling System That Powers Itself During Nuclear Plant Blackouts

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Imagine a nuclear power plant loses all electricity — no pumps, no fans, nothing works. The fuel inside is still hot and needs cooling or things get dangerous fast. This project built a compact backup cooling system that runs on the heat itself, like a self-winding watch that never needs a battery. It uses supercritical CO2 (basically carbon dioxide squeezed until it behaves like a dense fluid) to carry heat away automatically, no external power needed.

By the numbers

consortium partners

countries involved (CZ, DE, NL)

industrial partners in consortium

total project deliverables

demonstration deliverables with hardware

33%

industry participation ratio

The business problem

What needed solving

Nuclear power plants face a critical vulnerability: if all external power is lost (station blackout), conventional cooling pumps stop working and residual heat from the fuel can lead to dangerous conditions — as demonstrated at Fukushima. Current backup systems still depend on external power sources, diesel generators, or active components that can fail. The industry needs a truly passive, self-sustaining cooling solution that works without any grid connection.

The solution

What was built

The project built compact heat exchanger hardware, validated its performance through experiments and created performance maps, and assembled a demonstration unit installed in a glass model facility at GfS. Numerical simulations using the ATHLET code confirmed the system's capability across multiple accident scenarios. In total, 20 deliverables were produced including 3 dedicated hardware demonstrations.

Audience

Who needs this

Nuclear power plant operators running BWR or PWR reactorsReactor designers developing next-generation nuclear plantsSpent fuel storage facility managersNuclear safety equipment manufacturersNational nuclear regulators evaluating passive safety systems

Business applications

Who can put this to work

Nuclear power generation

enterprise

Target: Nuclear power plant operators and utilities

If you are a nuclear utility managing aging BWR or PWR reactors — this project developed a self-powered backup cooling system that kicks in automatically during station blackouts. The sCO2-HeRo system removes residual heat from fuel without any external power, giving you a new safety layer for beyond-design-basis accidents. A demonstration unit was built and tested in a glass model with validated performance maps from 3 demo deliverables.

Nuclear reactor engineering

enterprise

Target: Reactor designers and nuclear equipment manufacturers

If you are a reactor engineering firm designing next-generation plants — this project produced compact heat exchanger hardware and turbo-machine sets using supercritical CO2 Brayton cycles specifically sized for decay heat removal. The system was validated through CFD simulations and small-scale experiments across a 6-partner consortium spanning 3 countries. This gives you a proven component design for passive safety systems.

Nuclear decommissioning and spent fuel management

enterprise

Target: Spent fuel storage facility operators

If you manage spent fuel pools or dry cask storage facilities and worry about cooling loss scenarios — this project built a self-launching, self-sustaining cooling system that works without grid power. The compact design was demonstrated with validated performance maps, meaning it can be retrofitted into existing storage facilities as a backup heat removal layer.

Frequently asked

Quick answers

What would this system cost to implement at a nuclear plant?

The project data does not include specific cost figures or pricing estimates. The system uses compact heat exchangers that were either purchased commercially or custom-manufactured based on technical assessment. Cost would depend on plant-specific engineering and regulatory approval processes.

Can this scale to full-size commercial reactors?

The project demonstrated the concept at small scale using a glass model and compact heat exchanger hardware. Numerical validation was performed using the German nuclear code ATHLET for different accident scenarios. Scaling to full commercial reactor size would require further engineering and licensing work beyond this project's scope.

Who owns the intellectual property and how can we license it?

The project was coordinated by Universität Duisburg-Essen (Germany) under an EU Research and Innovation Action with 6 partners across 3 countries. IP ownership would follow the EU grant agreement terms, typically shared among consortium members. Licensing discussions would need to involve the coordinator and relevant industrial partners.

Does this work for both existing and new reactor types?

Yes. According to the project objective, the system improves safety of both currently operating and future BWRs (boiling water reactors) and PWRs (pressurized water reactors). This means it was designed as both a retrofit solution and a feature for new reactor designs.

How does this meet nuclear regulatory requirements?

The system was validated using the German nuclear code ATHLET, which is a recognized tool in nuclear safety analysis. The project tested performance across a range of accident scenarios including beyond-design-basis events. Regulatory approval would still require plant-specific licensing, but the validated simulation results provide a strong technical foundation.

What was actually built and tested?

The consortium built compact heat exchanger hardware, performed basic experiments to verify operation, created validated performance maps, and installed a demonstration unit in a glass model. A total of 20 deliverables were produced, including 3 dedicated demonstration deliverables covering heat exchanger design, testing, and integration.

Consortium

Who built it

The sCO2-HeRo consortium brings together 6 partners from 3 countries (Germany, Czech Republic, Netherlands), with a mix of 3 universities, 2 industrial partners, and 1 research organization. The 33% industry ratio signals genuine industrial interest, though the absence of any SMEs and the academic-heavy composition (led by Universität Duisburg-Essen) means commercialization would need additional industrial champions. The 2 industrial partners provide practical engineering credibility, while the multi-country spread across key European nuclear markets (Germany for decommissioning expertise, Czech Republic as an active nuclear operator) adds real-world relevance.

UNIVERSITAET DUISBURG-ESSENCoordinator · DE
CENTRUM VYZKUMU REZ SROparticipant · CZ
GFS GESELLSCHAFT FUR SIMULATORSCHULUNG MBHparticipant · DE
UNIVERSITY OF STUTTGARTparticipant · DE
UJV REZ ASparticipant · CZ
TECHNISCHE UNIVERSITEIT DELFTparticipant · NL

How to reach the team

Universität Duisburg-Essen, Germany — nuclear engineering department. SciTransfer can help identify the right contact person.

Order a report on this consortium See UNIVERSITAET DUISBURG-ESSEN profile →

Next steps

Talk to the team behind this work.

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