0.00
Metric Tons of CO2e
";details+="Natural Gas: "+v2+" therms/mo × 12 mo × 11.7 lbs/therm = "+co2Gas.toFixed(2)+" lbs CO2
";}if(type==='total'||type==='travel'){co2Travel=(v3*0.79);details+="Travel: "+v3+" miles/yr × 0.79 lbs/mile = "+co2Travel.toFixed(2)+" lbs CO2
";}var totalLbs=co2Electricity+co2Gas+co2Travel;var metricTons=totalLbs/2204.62;details+="Total Pounds: "+totalLbs.toFixed(2)+" lbs / 2204.62 lbs per Metric Ton = "+metricTons.toFixed(4)+" tons";if(showSteps){stepBox.innerHTML=details;stepBox.style.display='block';}else{stepBox.style.display='none';}document.getElementById('resultValue').innerHTML=metricTons.toFixed(2);document.getElementById('answer').style.display='block';}
Carbon Footprint Calculator Use
A carbon footprint calculator is a vital tool for understanding your personal impact on the environment. By measuring the greenhouse gas emissions associated with your lifestyle, you can identify the most effective ways to reduce your environmental impact. This calculator specifically targets the three largest contributors to a household's footprint: electricity, heating (natural gas), and transportation.
To get the most accurate results, have your utility bills and vehicle odometer readings ready. You can calculate your total annual footprint or focus on specific sectors like home energy or travel.
- Avg. Monthly Electricity (kWh)
- Enter the amount of kilowatt-hours (kWh) your household uses on average each month. This is found on your electric bill.
- Avg. Monthly Gas (Therms)
- Enter your monthly consumption of natural gas in therms. If your bill uses MCF or CCF, convert these to therms before entering.
- Annual Miles Driven
- The total distance you travel in your personal gasoline vehicle over the course of one year.
How It Works
This carbon footprint calculator uses standard EPA (Environmental Protection Agency) emission factors to convert raw energy usage into metric tons of CO2 equivalent (CO2e). The formula calculates annual totals based on your monthly inputs and then converts those pounds into metric tons.
Annual CO2e (Metric Tons) = [ (kWh × 12 × 0.92) + (Therms × 12 × 11.7) + (Miles × 0.79) ] / 2204.62
- Electricity Factor (0.92): Represents the average lbs of CO2 produced per kWh in the US power grid.
- Natural Gas Factor (11.7): The pounds of CO2 emitted per therm of natural gas burned.
- Vehicle Factor (0.79): Represents the average emissions per mile for a mid-sized gasoline car (approx. 25 MPG).
- Metric Ton Conversion (2204.62): Standard conversion factor to move from US pounds to International Metric Tons.
Calculation Example
Example: A typical US household using 800 kWh of electricity per month, 50 therms of gas per month, and driving 10,000 miles per year.
Step-by-step solution:
- Electricity: (800 × 12) × 0.92 = 8,832 lbs CO2
- Gas: (50 × 12) × 11.7 = 7,020 lbs CO2
- Travel: 10,000 × 0.79 = 7,900 lbs CO2
- Total Weight: 8,832 + 7,020 + 7,900 = 23,752 lbs
- Metric Tons: 23,752 / 2204.62 = 10.77 Metric Tons
Common Questions
What is a good carbon footprint?
In the United States, the average personal carbon footprint is approximately 16 tons per year, one of the highest in the world. Globally, the average is closer to 4 tons. To limit global warming, the goal for everyone is to drop below 2 tons per year by 2050.
How can I lower my electricity footprint?
Switching to LED light bulbs, using smart thermostats, and purchasing Energy Star appliances can significantly reduce kWh consumption. Additionally, many utility companies allow you to "opt-in" to renewable energy sources like wind or solar.
Does this calculator include air travel?
This specific calculator focuses on home and automotive impact. Air travel is highly variable based on flight duration and altitude, but generally, one cross-country round-trip flight adds approximately 1.5 to 2.0 metric tons to your individual footprint.