Flute: Enabling a Battery-Free and Energy Harvesting Ecosystem for the Internet of Things

Nowadays, most Internet of Things (IoT) devices still operate on batteries, offering lifetimes of just a few years; leading to high maintenance costs and excess waste. Energy Harvesting (EH) in combination with super-capacitor charge storage offers a solution, however, it is considered complex and unreliable, hampering its real-world deployment. To address this problem, we contribute Flute, a power management system for building battery-free IoT deployments. Unlike prior work, Flute focuses on transforming existing IoT development boards into battery-free devices. Reliable operation is achieved through a combination of generic power management hardware and self-adaptive software enabling sustainable operation in the face of dynamic power supply and demand. We evaluate our approach through a series of diverse one-week solar EH scenarios and show that Flute efficiently harvests energy and achieves reliable operation for a range of unmodified IoT development boards using LTE-M and LoRa. Hence, Flute provides a promising foundation for building a battery-free and EH ecosystem for the Internet of Things.