As the number of Internet of Things (IoT) devices continues to grow, the demand for sustainable and maintenance-free energy solutions becomes increasingly critical. In particular, approaches that decrease dependence on traditional power supplies and mitigate the need for battery replacement are essential for a long-term IoT deployment. In light of this, we present a study assessing the industrial viability of perovskite-based solar energy harvesting for powering indoor IoT nodes. We developed a low-power sensor platform based on the EMB1061 SoC, incorporating Bluetooth Low Energy (BLE) communication to create an app for real-time power consumption monitoring, alongside high-precision HDC2080 and SHT4x temperature and humidity sensors. A key design feature for this node is the replacement of traditional chemical batteries with a 50F supercapacitor, chosen for its superior lifecycle and environmental sustainability.

The photovoltaic cell used in this work was a Pb-Free perovskite minimodule. The scale-up from laboratory Perovskite Solar Cells (PSCs) to Perovskite Solar Modules (PSMs) involves the setup of series connected devices, which enables the achieving of higher voltages compared to single cells. This connection is established by the selective etching of the specific layers that make up the PV device using a laser scriber, following the procedure described in [1].

To optimize energy harvesting, a Maximum Power Point Tracking (MPPT) circuit utilizing the off-the-shelf bq25504 controller was implemented. The system’s temporal behavior was characterized under standard indoor lighting conditions (600 lux). Baseline measurements indicated a system consumption of approximately 0.03 mAh, resulting in an estimated autonomy of 370 hours using a fully charged 50F capacitor without additional harvesting.

Comparative evaluations of the energy-harvesting configurations revealed distinct performance outcomes between the tested photovoltaic technologies. Under 600 lux illumination, a silicon-based cell coupled with the MPPT achieved a net surplus of 0.007 mAh relative to system consumption, theoretically enabling endless operation under constant illumination. In contrast, the specific perovskite configuration tested at the same 600 lux generated a maximum power output of 0.006 mW, which was insufficient to meet the active load. Furthermore, the total consumption rose to 0.031 mAh due to MPPT overhead, slightly reducing the autonomy to approximately 358 hours, around 15 days of continuous operation. However, stress tests with high illuminance (5000 lux) showed that the additional current injected reduces consumption to 0.013 mAh, which confirmed the functional viability of the perovskite MPPT integration. That suggests that either higher illumination levels, an increased active cell area, or higher power conversion efficiency will be required to achieve full energy neutrality in future designs..

This work highlights the critical trade-offs between cell efficiency, surface area, and illumination levels required for transitioning perovskite technology from laboratory settings to functional indoor IoT applications.