Photovoltaics offer a fresh alternative to traditional energy sources, enhancing safety and control through advanced monitoring systems in security and defence. Can these tiny devices, made from micrometre-thick semiconductor layers, really protect people or property? Yes, but in a unique way. They supply energy quietly, efficiently, and sustainably, even where no other power source can reach.
Remote Monitoring for Safer Spaces
Digital remote monitoring systems are becoming common in homes, commercial buildings, roads, airports, and borders. Thanks to advances in cameras and sensors, we can now track motion, measure speed with RADAR and LIDAR, and detect people, animals, or objects using infrared technology.
High-resolution cameras linked to a network transfer footage to servers running AI software. This software analyzes situations, identifies threats, and automatically recognizes faces or license plates.
Sensors also protect against environmental hazards. Smoke and heat detectors can prevent wildfires, carbon monoxide sensors alert residents of danger, and afterdamp detectors save lives in mines and refineries.
Challenges in Powering Remote Systems
Many monitoring systems are spread over large areas, often far from power lines, and require wireless control. Temporary installations, like construction sites, must stay fully operational. Traditional power cables are vulnerable to accidents or sabotage, and transformers and wiring in remote areas can cost more than the equipment itself.
Most electronics run on low-voltage DC. Lithium-ion batteries work but are heavy, sensitive to weather, and limited in lifespan. Photovoltaic cells combined with a charge controller and miniaturized battery offer a compact, flexible, and sustainable energy solution. Early monocrystalline silicon micro-modules are in use, though durability and integration still need improvement.
Military Applications of Photovoltaics
Modern warfare relies heavily on electronics for communication, enemy detection, weapon guidance, and drone operation. Traditional fuel generators are heavy, noisy, and generate heat, making them easy targets.
Thin-film, flexible photovoltaic modules can provide long-term energy quietly and safely. These rollable, portable panels can be integrated into backpacks or tents and deliver peak power up to 1 kW. Research is ongoing to reduce their visibility in optical and radar detection through special coatings and irregular shapes.
Promising Materials and Future Prospects
Materials like the Sb2S3 semiconductor, studied at TalTech’s Laboratory for Thin Film Energy Materials, are promising. They are inexpensive to produce via spray pyrolysis, efficient, and semi-transparent. This allows integration into windows, visors, and optical gear.
As photovoltaics advance, security systems will gain reliable, stealthy, and sustainable energy sources that improve safety in both civilian life and military operations.
Acknowledgement:
Work supported by the EU Horizon 2020 project 952509-5GSOLAR.
