Study of Low-Area PV Modules Under Indoor Natural Daylight for Autonomous Sensors

The rise of smart technologies and Internet of Things has heightened the need for reliable and sustainable power sources. Energy harvesting from the optical domain, using photovoltaic (PV) modules, offers a viable solution, although their response in indoor scenarios has not been systematically evaluated in the literature. In such a context, this letter experimentally studies the performance of low-area PV modules for autonomous sensors under indoor natural daylight. Ten PV modules, involving six different PV technologies, are under test and comparison. Considering these ten PV modules, the units of the III-V group are the most efficient (around 22%) in the range from 1000 to 10000 lx of indoor natural daylight. Assuming the high cost of this technology, the best alternatives are the perovskite and monocrystalline technologies; the former being better at 1000 lx (with an efficiency of 15%), whereas the latter at 10000 lx (17 %). It is also proven that, for all the PV modules under test and excluding halogen light, 1000 lx of natural daylight generate more power than 1000 lx of artificial lighting.