The credibility of every VCU comes down to one thing: the auditor needs to be able to verify, independently, that the claimed generation actually happened.
Here’s how that works in practice.
What data we collect
Crediting requires generation data from calibrated electricity meters that meet the project’s monitoring requirements. Inverter readings alone do not replace compliant metering. SCADA and monitoring platforms may transfer the meter data; we assess the underlying equipment and records.
The data is collected at intervals defined by the methodology, typically hourly or sub-hourly. We ingest it into our monitoring system and use it to calculate megawatt-hours generated for each monitoring period.
How the data becomes credits
The basic calculation is straightforward:
MWh generated × Verra’s approved grid emission factor = tonnes of CO₂ avoided
In practice, the methodology adds adjustments for technical losses, monitoring uncertainties, and grid emission factor revisions. We document these calculations against the methodology’s requirements and prepare the resulting tCO₂e figures for the verification audit.
Independent verification
A VVB (Validation and Verification Body, accredited by Verra) reviews:
- Whether the metering equipment is calibrated and trustworthy
- Whether the data ingestion preserves data integrity
- Whether the calculations are correct under the methodology
- Whether any anomalies (data gaps, unusual readings) have been investigated and resolved
For VCS 3659, SustainCERT verified the monitoring period from 10 November 2021 to 31 December 2024, and Verra issued 17,755 VCUs on 30 September 2026, with contributions from 17 commercial and industrial solar sites. View the project record and read the first issuance announcement.
What you need to do
Your installation needs a calibrated electricity meter that meets the project’s monitoring requirements. If yours doesn’t have one, or if the calibration has lapsed, we help arrange installation or recalibration through our metering partners. We explain any installation or recalibration work, responsibilities and cost before you proceed.