Integrating plant microbial fuel cells into green infrastructure: Tackling heat islands and powering sensors

Green Infrastructure (GI) contributes to urban heat island mitigation and aesthetics, yet water supply monitoring remains labor-intensive. This study investigates bioelectricity generation using plant microbial fuel cells (PMFCs) integrated into a GI system constructed with recycled materials. Two GI models (120 × 50 × 60 cm) comprising three 20 cm layers of organic soil, recycled foamed glass (FWG), and decomposed granite were developed. Three PMFCs connecting in series with bamboo charcoal electrodes were embedded in the FWG layer beneath planted vegetation. Voltage was recorded every minute over 20 days and correlated with weather data. Results showed increased bioelectricity during summer driven by solar radiation, while precipitation and temperature had limited influence. In winter, voltage declined after one week. Peak voltage and power densities reached 1800 mV and 23 mW/m 2 (winter), and 1400 mV and 11 mW/m 2 (summer). Thermographic imaging revealed temperature differences exceeding 20 °C between the GI surface and adjacent concrete, highlighting GI's thermal regulation potential. • Utilization of recycled glass and bamboo in green infrastructure and plant microbial fuel cells. • An innovative biobattery has been designed to be placed under the green infrastructure • Seasonal impact of bioelectricity generation has been conducted at the outdoor GI • The heat island problem can be solved and simultaneously generate bioelectricity