REFLEX · Project

Two-Way Energy Storage System That Converts Between Hydrogen and Electricity On Demand

energyPilotedTRL 6

Imagine a device that works like a rechargeable battery, but instead of storing charge, it stores hydrogen. When you have extra solar or hydro power, it splits water into hydrogen and stashes it away. When the lights need to come back on, the same device flips into reverse and turns that hydrogen back into electricity and heat. The REFLEX team built and tested this two-in-one "Smart Energy Hub" at a real technology park in Italy, hooked up to local solar panels and a small hydro plant — proving it works outside the lab.

By the numbers

TRL 3 → 6

Technology maturity advancement achieved

Consortium partners across 6 countries

60%

Industry partners in the consortium

SMEs involved in development

Countries represented (DK, EE, ES, FI, FR, IT)

The business problem

What needed solving

Industrial parks, remote facilities, and renewable energy operators face the same headache: solar and wind produce power when nobody needs it, and go quiet when demand peaks. Conventional batteries degrade fast and store limited energy, while one-way electrolyzers can make hydrogen but cannot generate power back. Businesses need a single, flexible system that absorbs surplus green energy and delivers electricity plus heat on demand — without installing two separate machines.

The solution

What was built

The team built and field-tested a "Smart Energy Hub" — a reversible solid oxide cell system that switches between electrolyzer mode (making hydrogen from excess electricity) and fuel cell mode (making electricity and heat from hydrogen). The system was installed at a technology park in Italy, connected to local solar and mini-hydro sources, with completed grid integration. Seven deliverables were produced, including the system installation and grid integration layout.

Audience

Who needs this

Technology park and industrial estate operators seeking on-site energy storageRenewable energy developers facing curtailment lossesDistrict heating companies looking to integrate hydrogen into CHP systemsMicrogrid developers building self-sufficient energy communitiesLarge manufacturers with on-site renewables and variable power demand

Business applications

Who can put this to work

Industrial & Technology Parks

mid-size

Target: Technology park operators and industrial estate managers

If you are a technology park operator dealing with rising electricity costs and unreliable grid supply — this project developed a modular Smart Energy Hub that stores your excess solar or hydro energy as hydrogen and feeds it back as electricity and heat when you need it. The system was demonstrated at a real technology park (Envipark), integrated with local renewables and the grid. Because it is modular, you can start with one unit and scale up as your park grows.

Renewable Energy Integration

any

Target: Renewable energy operators and microgrid developers

If you are a renewable energy developer struggling with curtailment — your wind or solar farm produces power when nobody needs it, and you lose revenue. This project built a reversible solid oxide cell system that absorbs excess electricity by making hydrogen, then generates power back at round-trip efficiencies far above conventional batteries. The technology was validated from TRL 3 to TRL 6, meaning it is past the lab stage and ready for pilot partnerships.

District Heating & Combined Heat and Power

enterprise

Target: District energy companies and CHP plant operators

If you are a district heating company looking to decarbonize while keeping costs under control — the Smart Energy Hub produces both electricity and heat from hydrogen or other locally available fuels. Unlike conventional electrolyzers that only go one way, this system runs in reverse when heat demand spikes, eliminating the need for separate backup boilers. Scale-up studies were performed to evaluate performance across different product sizes and markets.

Frequently asked

Quick answers

What would a system like this cost to deploy?

The project does not publish specific unit pricing. However, the consortium performed techno-economic and market analyses (led by ENGIE) to evaluate costs at different scales. Interested buyers should contact the consortium for current cost projections based on their specific capacity needs.

Can this scale beyond a single building or park?

Yes. The Smart Energy Hub is explicitly designed as modular, built from multistack and multimodule arrangements. Scale-up studies were conducted to evaluate techno-economic performance at different product sizes for different markets, from single-site to district-level deployment.

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

The consortium includes both the technology developers (CEA, ELCOGEN, DTU for cells and stacks; SYLFEN for system manufacturing) and industrial end-users (ENGIE). SYLFEN, as the system manufacturer, is likely the primary licensing or sales contact. IP terms would follow the consortium agreement under Horizon 2020 rules.

Has this actually been tested in real conditions?

Yes. The system was demonstrated in-field at a technology park (Envipark in Italy), coupled to local solar and mini-hydro renewable sources, providing electricity and heat to the park headquarters. A dedicated deliverable covers the system installation, permissions, and grid integration layout.

What efficiency can I expect compared to regular batteries or electrolyzers?

The project specifically targeted high power-to-power round-trip efficiency as a key performance metric, demonstrated during the field test. Exact efficiency figures are not stated in the available project summary — the consortium can provide measured performance data from the Envipark demonstration.

How mature is this technology — is it ready to buy?

The project moved the technology from TRL 3 (lab-validated) to TRL 6 (demonstrated in a relevant environment). This means it has been proven in real-world conditions but is not yet a commercial off-the-shelf product. Pilot partnerships or pre-commercial procurement would be the logical next step.

Does this comply with EU hydrogen and energy storage regulations?

The project was funded under the Fuel Cells and Hydrogen Joint Undertaking (topic FCH-02-3-2017) and the field demonstration required formal installation permissions and grid integration approvals. Regulatory compliance was addressed as part of the demonstration phase.

Consortium

Who built it

The REFLEX consortium is unusually well-balanced for commercialization: 60% of its 10 partners are industrial, with 3 SMEs bringing agility alongside heavyweight players. CEA (French atomic energy commission) and DTU (Technical University of Denmark) provide deep solid oxide cell expertise, while SYLFEN handles system design and manufacturing — making them the likely route-to-market. ENGIE, one of Europe's largest energy companies, led the techno-economic and market analysis, signaling serious commercial interest. ELCOGEN (Estonia) supplies the core cell technology. VTT (Finland) contributed system modelling, and GPTech and University of Seville handled power electronics. Envipark (Italy) hosted the real-world demonstration. This mix of research excellence, manufacturing capability, and major-utility commercial pull across 6 countries makes the technology well-positioned for European market entry.

COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVESCoordinator · FR
SYLFENparticipant · FR
AKTSIASELTS ELCOGENparticipant · EE
TEKNOLOGIAN TUTKIMUSKESKUS VTT OYparticipant · FI
ENGIEparticipant · FR
DANMARKS TEKNISKE UNIVERSITETparticipant · DK
GREEN POWER TECHNOLOGIES SLparticipant · ES
PARCO SCIENTIFICO TECNOLOGICO PER LAMBIENTE ENVIRONMENT PARK TORINO SPAparticipant · IT
UNIVERSIDAD DE SEVILLAparticipant · ES

How to reach the team

CEA (Commissariat à l'énergie atomique) is the coordinator. For commercial inquiries, SYLFEN (system manufacturer) or ENGIE (market analysis lead) may be more direct contacts.

Order a report on this consortium See COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES profile →

Next steps

Talk to the team behind this work.

Want an introduction to the REFLEX team or a detailed technology brief tailored to your energy storage needs? Contact SciTransfer — we connect businesses with EU research teams.

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