CO2 emissions

What this value means

The CO2 value in Zerofy is an estimate of the carbon intensity of electricity consumed in your country (gCO2/kWh), combined with your electricity usage.

How we calculate it

We combine:

  • Generation by production type from ENTSO-E (for example coal, gas, wind, hydro)
  • Cross-border physical power flows between countries
  • Technology emission factors (IPCC-based)

This gives a consumption-based estimate: it reflects both local generation and imported electricity.

Preliminary and updated values

To provide timely data, we first show a country-average estimate.

Later, when ENTSO-E actual flow and generation data is complete (usually for the previous day), we update the value using flow-tracing.

Because of this, historical values can be refined after initial publication.

Flow-tracing in short

Flow-tracing follows the physical electricity flows between connected countries and applies proportional mixing at each node in the grid.

In practice:

  • Production-based view: uses only a country’s own generation mix
  • Flow-traced view: adjusts that value by including imported electricity and excluding exported electricity

This is why flow-traced intensity is usually a better proxy for consumption-based emissions.

Why values can differ over time

  • ENTSO-E actual data is published with delay (typically around 1-2 days)
  • Cross-border imports/exports can materially change national consumption intensity
  • Some generation categories are reported with limited detail and are handled conservatively

References