Enhanced and Sustainable Indoor Carbon Dioxide Monitoring by Using Ambient Light to Power Advanced Biological Sensors

Abstract

Enhancing carbon dioxide (CO₂) detection is crucial for improving indoor air quality and environmental surveillance. Traditional CO₂ sensors face drawbacks like high costs, large sizes, environmental impact, and reliance on external power, limiting their practicality for continuous indoor monitoring. In this research, an innovative indoor CO₂-sensing system using a self-powered bio-solar cell (BSC) platform is introduced. Utilizing cyanobacteria as a sensitive biocatalyst and sustainable power source, the system offers a cost-effective, eco-friendly, and maintenance-free alternative to conventional sensors. It operates by monitoring electron-transfer processes in cyanobacteria during photosynthesis, converting CO₂ and water into oxygen and chemical energy, enabling accurate CO₂ level monitoring. The system responds to CO₂ fluctuations and issues alerts when levels are outside the recommended range of 500–1000 ppm for human health and productivity. A self-sustaining configuration of eight BSCs—one for sensing and others for power generation—ensures continuous operation without external power. An integrated energy-harvesting board efficiently manages power distribution to a microcontroller and display system for real-time data visualization, with the array producing up to 400 μW. Additionally, a machine-learning model interprets BSC outputs to accurately quantify CO₂ levels, enhancing the sensor's adaptive performance.