About the Electricity Carbon Calculator
CO₂ emissions from your electricity use, and how a greener tariff changes them.
Also known as: electricity co2 calculator, grid emissions calculator, power carbon intensity.
How to use this calculator
- Enter electricity used, grid carbon intensity, green tariff intensity.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
kg CO₂ = kWh × g/kWh ÷ 1000
Worked example
Using the values pre-filled in the calculator above:
- Electricity used = 3,500 kWh/year
- Grid carbon intensity = 233 g/kWh
- Green tariff intensity = 20 g/kWh
the calculator returns:
- Annual emissions: 815.5 kg CO₂
- In tonnes: 0.8155
- On a green tariff: 70 kg CO₂
- Reduction from switching: 745.5 kg CO₂