Plant microbial fuel cells as a bioenergy source used in precision beekeeping

Urban beekeeping is increasing due to growing populations, adopting Internet of Things (IoT), technology 4.0, and development of smart cities. In this paper, we proposed an energy-autonomous wireless sensors node (EAWSN) for beehive's humidity and temperature inside/outside detection. This sensor platform can harvest energy from plant microbial fuel cells (PMFC) sources, powering sensors with a current as low as 1.96 mA and communicating via Bluetooth Low Energy (BLE). The PMFC-array produces the maximum power of 5.8 mW at an open circuit voltage of 4.6 V and a short circuit current of 3.92 mA. The ultra-low-power consumption of the system allows for performing whole-time continuous BLE transmissions. The main benefit is the elimination of maintenance associated with changing and disposing of batteries. EAWSN uses a PMFC that provides continuous and virtually endless power and avoids using expensive and bulky storage devices such as supercapacitors or batteries. The functionality of the system is demonstrated by experimental measurements in an urban context. Besides, the system probes the concept of an eco-friendly battery-free that allows the coexistence of the environment, PMFC technology, and IoT.