watt hour CO2e equivalent (Wh→CO2e)
1 watt hour CO2e equivalent = 0.000445 kilograms CO2e
What is watt hour CO2e equivalent?
Watt hour CO2 equivalent is a carbon emissions unit expressing the greenhouse gas equivalent of producing one watt hour of electricity. It is used in energy labelling, lifecycle assessments, and grid carbon intensity calculations.
Notes: Approximate grid factor
Real-world uses
Watt hour CO2e equivalent is used to estimate the carbon impact of small-scale electricity consumption, such as charging a phone or running a light bulb. IoT device power budgets and embedded system lifecycle analyses may reference Wh-to-CO2e conversion factors.
History
Wh-to-CO2e conversion factors emerged from life cycle assessment (LCA) methodologies developed in the 1990s. The specific factor depends on the local electricity grid mix and is published by agencies like the IEA and national environmental bodies.
Common mistakes
Applying a single fixed emission factor globally. Grid carbon intensity varies dramatically: France (mostly nuclear) emits about 50 g CO2e/kWh, while India (coal-heavy) emits about 700 g CO2e/kWh. The default factor is only an approximation.
When is this conversion used?
Converting watt hour CO2e equivalent to kilogram CO2e is useful in the carbon emissions domain when comparing values across different measurement standards or applying formulas that require a specific unit.
How to convert watt hour CO2e equivalent to kilogram CO2e
To convert watt hour CO2e equivalent to kilogram CO2e, multiply the value by 0.000445.
Conversion formula (from base unit)
x * 0.000445
Measurement standards
The Greenhouse Gas Protocol, maintained jointly by the World Resources Institute and the World Business Council for Sustainable Development, is the de facto global standard for measuring and reporting greenhouse gas emissions across corporate, project, and product life-cycle scopes.
Did you know?
A single transatlantic round-trip flight from London to New York generates roughly 1.6 tonnes of CO₂ per passenger — nearly a quarter of the average annual carbon footprint of a person in France.
| watt hours CO2e equivalent | kilograms CO2e |
|---|---|
| 0.1 | 0.0000445 |
| 0.5 | 0.0002225 |
| 1 | 0.000445 |
| 2 | 0.00089 |
| 5 | 0.002225 |
| 10 | 0.00445 |
| 25 | 0.011125 |
| 50 | 0.02225 |
| 100 | 0.0445 |
| 250 | 0.11125 |
| 500 | 0.2225 |
| 1,000 | 0.445 |
Full watt hour CO2e equivalent conversion table
| Unit | Value | Factor |
|---|---|---|
| kilogram CO2e | 1 Wh→CO2e = 0.000445 kg CO2e | × 0.000445 |
| gram CO2e | 1 Wh→CO2e = 0.445 g CO2e | × 0.445 |
| tonne CO2e | 1 Wh→CO2e = 4.450000e-07 t CO2e | × 4.450000e-07 |
| kilowatt hour CO2e equivalent | 1 Wh→CO2e = 0.001 kWh→CO2e | × 0.001 |
| megawatt hour CO2e equivalent | 1 Wh→CO2e = 0.000001 MWh→CO2e | × 0.000001 |