FOXES · Project

Self-Powered Wireless Sensors That Never Need Battery Replacement

energyTestedTRL 5

Imagine a tiny power station the size of a coin that harvests sunlight and stores it for later — no batteries, no wires, no toxic materials. That's what FOXES built: a combined solar cell and capacitor made from safe, lead-free materials that generates enough energy to keep a wireless sensor running day and night. Think of it like a self-charging watch, but for air quality sensors or smart city monitors. They even tested the whole thing in a real city to prove it works outside the lab.

By the numbers

>10%

Solar cell efficiency (lead-free perovskite)

>50 J/cm3

Capacitor energy density (thin film)

>250 mJ/day

Energy generation target per device

<3 mJ/day

Gas sensor energy consumption

EUR 3,992,100

EU funding invested in development

5 partners, 4 countries

Consortium size and geographic spread

The business problem

What needed solving

Billions of IoT sensors deployed in cities, farms, and factories still depend on batteries that need regular replacement — creating massive maintenance costs, environmental waste, and limiting where sensors can be placed. Current solar-powered alternatives often use toxic lead-based materials that conflict with EU environmental regulations. Companies need a clean, self-sustaining power source small enough to embed anywhere and reliable enough to run unattended for years.

The solution

What was built

FOXES built a complete self-powered sensor system: a lead-free perovskite solar cell (targeting over 10% efficiency) combined with a high-density thin film capacitor (over 50 J/cm3) and integrated with gas sensors, control electronics, and wireless communications. Final prototypes were assembled into an IoT Bundle and demonstrated in a real city deployment.

Audience

Who needs this

Smart city IoT platform providers deploying thousands of environmental sensorsIndustrial gas detection companies needing maintenance-free remote monitoringPrecision agriculture firms wanting autonomous field sensor networksBuilding management companies monitoring indoor air quality across large portfoliosLogistics and fleet companies tracking environmental conditions in remote locations

Business applications

Who can put this to work

Smart City Infrastructure

mid-size

Target: Municipal IoT solution providers and smart city integrators

If you are a smart city solutions provider struggling with the cost and logistics of replacing batteries in thousands of distributed sensors — FOXES developed a self-powered sensor node that generates over 250 mJ/day from sunlight while consuming less than 3 mJ/day. This eliminates battery replacement entirely, dramatically cutting maintenance costs across large sensor networks. The system was demonstrated in a real city deployment as proof of concept.

Industrial Environmental Monitoring

any

Target: Gas detection and environmental monitoring equipment manufacturers

If you are an environmental monitoring company deploying gas sensors in hard-to-reach or remote locations — FOXES created a fully autonomous sensor node combining a lead-free perovskite solar cell with over 10% efficiency and a thin film capacitor with over 50 J/cm3 energy density. The light-activated gas sensor draws less than 3 mJ/day, meaning the system stays powered indefinitely without grid connection or battery swaps. Final functional prototypes of the gas sensor and control electronics have been completed.

Agriculture & Precision Farming

SME

Target: Precision agriculture sensor and IoT platform companies

If you are a precision farming company needing wireless soil, air, or crop sensors across large fields where power lines and regular maintenance are impractical — FOXES built a zero-emission, portable energy supply using only safe, recyclable oxide materials. The system generates over 250 mJ/day from solar energy and stores surplus in a high-density capacitor for overnight operation. With 5 partners across 4 countries validating the technology, this could power distributed agricultural sensor networks autonomously.

Frequently asked

Quick answers

What would this energy supply system cost compared to current battery solutions?

The project specifically targeted low-cost and scalable processes like spin coating and spray pyrolysis, using no critical raw materials. While exact unit pricing is not published, the manufacturing approach avoids expensive vacuum deposition methods. Cost savings would compound over time by eliminating recurring battery replacement across large sensor networks.

Can this be manufactured at industrial scale?

The FOXES system was designed with scalability in mind, using processes like spin coating and spray pyrolysis that are inherently scalable. However, the project reached proof-of-concept demonstration stage with prototypes. A roadmap for scaling up the FOXES technology was defined as part of the project deliverables, but industrial-scale manufacturing has not yet been demonstrated.

What is the IP and licensing situation?

FOXES was funded as an EU Research and Innovation Action (RIA) with EUR 3,992,100 in EU contribution across 5 partners. IP generated during the project is typically owned by the partners who created it, with access rights defined in the consortium agreement. Licensing arrangements would need to be negotiated with the coordinator, Materials Center Leoben Forschung GmbH in Austria.

How long does the system actually run without sunlight?

The system stores solar energy surplus in a multilayer thin film capacitor with over 50 J/cm3 energy density. With the gas sensor consuming less than 3 mJ/day and the system generating over 250 mJ/day, there is substantial energy surplus for storage. The combined system was tested against gas mixtures during variable irradiation conditions, confirming operation during low-light periods.

Is this technology ready to integrate into existing IoT products?

Final IoT Bundle prototypes were built and tested with the Power Cube energy supply. The system includes sensor, control electronics, and wireless communications. Commercial low-power ASIC and data transmission solutions were adopted for sensor operation, which should ease integration with existing IoT architectures. However, this remains at prototype and proof-of-concept stage.

What regulations does this address?

FOXES uses fully lead-free perovskite materials and avoids harmful chemicals and critical raw materials, directly addressing EU RoHS and REACH compliance concerns. The recyclability and end-of-life disposability were explicitly designed in, which aligns with upcoming EU battery regulation requirements for IoT devices.

What is the timeline to a commercial product?

The project ran from October 2020 to March 2025 and delivered final prototypes plus a city-level proof-of-concept demonstration. A scaling roadmap was defined. Based on available project data, the technology would likely need 2-3 more years of engineering and industrialization before a commercial product launch.

Consortium

Who built it

The FOXES consortium is compact — 5 partners across Austria, Germany, Spain, and Portugal — but entirely research-focused with 0 industry partners (2 universities, 2 research organizations, 1 other). The coordinator, Materials Center Leoben in Austria, is classified as both a research center and an SME, which suggests some commercial orientation. With 2 SMEs in the consortium and EUR 3,992,100 in EU funding, the project had solid resources for technology development. However, the absence of any industrial manufacturer or end-user company means commercialization will require new partnerships — this is both a gap and an opportunity for companies looking to license or co-develop the technology without competing against an existing industry partner.

MATERIALS CENTER LEOBEN FORSCHUNG GMBHCoordinator · AT
UNINOVA-INSTITUTO DE DESENVOLVIMENTO DE NOVAS TECNOLOGIAS-ASSOCIACAOparticipant · PT
GESELLSCHAFT FUR ANGEWANDTE MIKRO UND OPTOELEKTRONIK MIT BESCHRANKTERHAFTUNG AMO GMBHparticipant · DE
BERGISCHE UNIVERSITAET WUPPERTALparticipant · DE
UNIVERSITAT DE BARCELONAparticipant · ES

How to reach the team

Materials Center Leoben Forschung GmbH, Austria — research SME specializing in advanced materials

Order a report on this consortium See MATERIALS CENTER LEOBEN FORSCHUNG GMBH profile →

Next steps

Talk to the team behind this work.

Want an introduction to the FOXES team to discuss licensing or co-development? SciTransfer connects businesses with EU research teams — contact us for a tailored briefing.

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