Constellation’s Hourly Carbon-Free Energy Agreement with Microsoft

Project location
United States
EnergyTag audited
Temporal matching
1 hour
Geographical matching
ISO level
Energy tracked
170 GWh/y
Tracking method
Hourly matching platform/Granular Certificates

Landmark agreement combines the environmental attributes of up to 35% nuclear power with hourly carbon-free energy matching to help a Virginia data center operate on nearly 100% clean power.

Key takeaways:

  1. Time-aligned nuclear attributes of up to 35% of Microsoft’s data center usage complement Microsoft’s new wind and solar.
  2. Performance tracked on Constellation’s Azure-based hourly matching platform.
  3. Corresponding timestamped, sub-MWh EACs retired in PJM GATS.

Next steps:

  1. Scale the product to other interested customers.
  2. Support the development of hourly CFE matching in other regions.


Project stage