Car Carbon Footprint Calculator
Estimate your car annual carbon footprint from the distance driven and the average fuel consumption. Find out how much CO₂ you emit each year by driving.
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Annual vehicle carbon footprint: factors by fuel
How much a vehicle emits hinges on what it burns. Figure roughly 2.3 kg CO2/L of gasoline, 2.7 kg/L of diesel and 2.4 kg per kg of sugarcane ethanol on a well-to-wheel basis, which counts both combustion and the production of the fuel. The math itself is short: CO2/year = (km/year ÷ km/L) · factor. Take an example. A popular car covering 15,000 km/year at 12 km/L on gasoline burns 1,250 L, so 1,250 · 2.3 works out to 2.9 t CO2/year. Switch that same car to ethanol and you drop to about 1.5 t/year, because the factor is lower and the cane pulls CO2 out of the air while it grows. A Brazilian EV lands near 0.3 t/year in equivalent CO2, since the country's grid is one of the cleanest anywhere (75% hydro plus solar and wind).
Applications: corporate ESG and offset
This number shows up in a few places. It feeds corporate ESG reporting (scope 1 of GHG Protocol for owned fleets), it backs CO2 offset through programs like Carbono Cidadão and SOS Mata Atlântica (roughly R$ 30-80 per ton offset), and it helps when you have to choose between technologies, weighing gasoline against ethanol, hybrid or EV by their annual emissions. There's also the personal awareness angle, where the Brazilian average sits around 2.5 t CO2/year per car. Firms covered by CDP and the EU CSRD now ask for this figure from fleet drivers and approved suppliers.
FAQ
Why is ethanol cleaner? The cane absorbs CO2 as it grows, so once you net that out the emission ends up around 30-40% of what the gasoline equivalent would be.
Is the EV really zero? Not quite. In Brazil it stays very low (around 0.3 t/year) thanks to the clean grid. Run the same car where coal dominates the power supply, like China or Poland, and it can put out more than 3 t/year.
How much does it cost to offset? Run the numbers: 3 t CO2 × R$ 50 = R$ 150 per year on certified projects such as REDD+ and reforestation. That's not much money for the amount of carbon you're cancelling out.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.