Ground sensors and satellites: same evidence chain, different roles

Sustainability platforms increasingly market satellite-powered ESG features. The implication is usually: skip the BMS integration, just buy our satellite data. That implication is wrong, and the architectural confusion behind it is dangerous for any customer who needs the report to survive an audit.

Ground sensors are operational truth

A BACnet adapter on a hospital BMS reads a CO2 level of 682 ppm from a Wing-3 ICU sensor. That reading is calibrated, has a maintenance schedule, has a manufacturer-specified accuracy band, and resolves to a specific zone with named occupants. Ground sensors are facility-level operational truth.

Remote evidence is context

Satellite, drone, weather, GIS, and public datasets serve a different role. They establish climate exposure, regional air quality context, methane plume corroboration, vegetation indices, land disturbance, heat-island mapping. They are external context that complements ground readings. They do not replace them.

Why the same evidence chain

Both ground and remote observations land in the same canonical evidence chain at EcoVeraZ. Both are content-hashed, RFC 3161 anchored, and methodology-documented. The methodology pack records which observations are remotely sensed, which are ground-sensor measured, which are estimated, and which are derived. Auditors can trust the report because the provenance for every value is explicit.

Architectural commitment

Remote-sensing outputs are classified as observed-remotely, estimated-from-remote-sensing, or derived-from-public-dataset. They are never classified as certified emissions, verified compliance, or regulator determination. This rule is enforced at the methodology layer, not by convention.