CO2, Sensor, Ventilation, Occupancy, Indoor Air Quality
There is a significant opportunity to improve building energy efficiency and indoor environmental quality by accurately monitoring CO2 levels. However, current CO2 sensors tend to be expensive or require regular recalibration. This work presents research related to the initial development and evaluation of two novel CO2 sensors based on chemiresistive and resonant mass sensing techniques. Prototype sensors were assessed in a bench-top test chamber at temperatures, humidity levels, and CO2 concentrations, typical of indoor environments. Under these conditions, prototype sensors required only 60 mW of power, or less. Further, each sensor was developed to have a footprint of less than 25 mm2 and a cost of less than $50. Given the relative low cost, small size, and potential for low power consumption, these sensors may serve as an attractive alternative to the commercial CO2 sensors that are currently available.