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According to some experts, by 2025 we will have to live with about 75,000,000,000 (seventy-five billion) IoT devices, most of which will be located inside our homes and workplaces.
Obviously these devices need energy to function and be autonomous enough to be able to forget about them, this on the outside can be solved with solar cells but on the inside it gets complicated.
The fundamental characteristic of this type of sensor is its small size and the fact that, in some cases, they are located in places that are difficult to access, so that no cables or batteries can be added to them, which may have operational problems.
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All this can be easily solved with a new development of indoor photovoltaic cells, that is, photovoltaic cells capable of generating energy taking advantage of the interior light of fluorescent lamps and LED lamps present inside buildings.
Research teams from various universities have developed new indoor photovoltaic cells that can convert up to 34% of light into electricity, with which to power a wide range of IoT sensors.
Silicon, which is the material normally used in today's solar cells, doesn't work as well under lamps as it does in the sun, but new technologies like perovskite cells and dye-sensitized materials are much more efficient at converting lighting artificial in electrical energy.
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This cheap energy technology, combined with RFID tags that cost a few pence each, would literally allow us to fill our environment with IoT sensors that make things easier for us.
Of course, the price to pay will be our intimacy and privacy that, where we already have little, with these gadgets we will lose them totally and definitely.
More information:
https://spectrum.ieee.org/energywise/energy/renewables/next-gen-solar-cells-harvest-indoor-lighting-iot-devices
Versión en español