GHG-R Flagship Destination

Ground Truth
A low-cost sensor unearths gigaton-scale soil CDR potential

Team: Alison Hoyt, Debbie Senesky, Kate Maher

Scaling low-cost measurements of soil CO₂ emissions - Natural climate solutions, such as climate-smart agriculture and ecosystem restoration, offer opportunities to remove atmospheric carbon at large scales. All these strategies change soil organic carbon reservoirs and greenhouse gas (GHG) exchanges at the soil surface. However, the scientific community lacks a clear understanding how much carbon the soil can store and for how long. 

The difficulty of measuring GHGs in the field drastically limits our ability to measure, report, and verify natural climate solutions. Existing GHG measurement tools are too expensive and inefficient to capture these processes at scale. For example, portable GHG sensors are costly ($40,000) and labor intensive. Eddy flux towers require extensive infrastructure and cannot capture spatial variability. 

To address these challenges, we plan to develop, refine, and deploy a low-cost, automated, autonomous flux sensor platform (< $100) that can measure CO₂ emissions accurately. The technology leverages recent advances in low-cost, commercially available, nondispersive infrared sensor technology developed to monitor industrial and residential air quality. To reduce noise and increase sensitivity, the platform relies on a flux chamber that stabilizes the local environment and the exchanges of CO₂ between soil and the atmosphere. We will deploy and test these chambers and the sensor platform at 15 California agricultural sites that are experimenting with soil-based CO₂ removal. Scalable, continuous, low-cost CO₂ flux measurements will provide the robust data needed to invest strategically in climate-smart agriculture and to validate soil carbon credits. 

This project continues work performed under the Accelerator’s first cohort, and the Accelerator is enabling this team to pilot the technology in the field.