How it works
Your electricity's carbon footprint is the kWh you use × how much CO₂ your grid releases to produce each kWh. That emission factor depends on the mix of coal, gas, nuclear, hydro, wind and solar where you live, so it varies enormously: Quebec and Tasmania run mostly on hydro, while Victoria still relies heavily on coal.
Pick your country, then your state or province where a figure is available. Electricity from your own solar panels or a certified green tariff is taken off first. To make the result easier to picture, it is compared with driving an average car, and priced at an offset rate you choose.
The formula
grid kWh = monthly kWh × 12 × (1 − share from solar or green tariff) CO₂e (kg) = grid kWh × emission factor (kg per kWh) car equivalent = CO₂e ÷ 0.403 kg per mile (0.25 kg per km) offset cost = CO₂e ÷ 1,000 × price per tonne
Worked example
| Home | Working | CO₂e a year |
|---|---|---|
| Average US home | 10,380 kWh × 0.367 | 3.81 t |
| Typical UK home | 2,700 kWh × 0.177 | 0.48 t |
| Australian home, Victoria | 4,920 kWh × 0.78 | 3.84 t |
| Same home, Tasmania | 4,920 kWh × 0.20 | 0.98 t |
The average US home's 3.8 tonnes is about the same as driving an average car 9,500 miles.
Frequently asked questions
How much CO2 does 1 kWh of electricity produce?
About 0.367 kg (0.81 lb) on average in the US (2023), 0.177 kg in the UK (2025 government factor), around 0.1 kg in Canada (2022) and from 0.20 kg in Tasmania to 0.78 kg in Victoria in Australia (2025).
What is the carbon footprint of an average home's electricity?
About 3.8 tonnes of CO₂e a year for the average US home and about 0.48 tonnes for a typical UK home, whose electricity use is much lower and grid cleaner.
How can I find my state's emission factor?
In the US, the EPA Power Profiler gives the factor for your grid region by ZIP code (eGRID). Australian state factors come from the National Greenhouse Accounts Factors, published each year.
Do solar panels cut my carbon footprint?
Yes: every kWh you use from your own panels replaces a kWh from the grid. Enter the share of your use that solar covers.
Are carbon offsets worth buying?
Quality varies widely. Cutting use and switching to clean electricity reduces emissions directly; if you do buy offsets, look for independently verified projects and be wary of very cheap credits.
Sources
- US: EIA, how much carbon dioxide is produced per kWh (0.81 lb, 2023).
- UK: Department for Energy Security and Net Zero, greenhouse gas conversion factors 2025.
- Canada: Canada Energy Regulator, provincial and territorial energy profiles (2022).
- Australia: DCCEEW, National Greenhouse Accounts Factors 2025.
- Car comparison: US EPA, greenhouse gas equivalencies calculator.
Estimates are for planning only and are not financial advice. Get written quotes before you buy.