Understanding the 2 Metric Tons Per Person Goal of the Under 2 MOU
This is an estimate of what two metric tons of C02 per person might look like based on my example and makes the goal more tangible. The average today is 19 metric tons per person per year, so the reduction will need to be substantial. Note for simplicity of understanding, I have rounded numbers so the math becomes more transparent.
1. A metric ton = 2200 lbs or 1000 Kg. Two Metric tons equals 4400 lbs.
2. Burning a gallon of gasoline creates 20 lbs of C02 (1) If we take a car that only gets 20 MPG, it creates 1 lb of C02 for every mile traveled. The average car distance traveled per person per year is around 12,000 miles. If we assume only 1 person in a car, that is 12,000 lbs and we are at almost 3x the goal just on automotive travel.
3. If the mileage doubles to 40 MPG (a reasonable average for a Prius or other economical automobile) then the12,000 miles translates into 6000 lbs. My wife drives her Prius mostly alone abpit 6000 miles per year creating 3000 lbs. of C02.
4. My older BMW only gets about 20 MPG on average and I drive alone most of the time. However I only drive about 600 miles per year or 600 lbs of C02.
5. I try to take VTA bus Mass Transit as much as possible. A VTA bus gets about 5 MPG and I estimate the usual passenger load is about 15 passengers. So we can estimate per person MPG as 75 (5 x 15). I take 3 trips per week, each about 20 miles. So that is 60 miles x 50 weeks or 3000 miles. At 75 Miles /Gallon / Person that is a total of 40 gallons. Diesels generate about 20 lbs of C02 per gallon so that is a total of 800 lbs of C02.
6. My wife and I live in a 2 bedroom apartment with electric heat but no air conditioning. We use about 400 kWh per month or 4800 kWh per year. The PGE factor is about 0.5 lbs per kWh so that translates into 2400 lbs.
So the average for the two of us is determined by the following.
- Prius 3000
- BMW 600
- Bus 800
- Electricity 2400
- Total 7800
- Per Person 3900
Conclusion: There are a number of items missing from this including any plane trips, electricity for clothes washing and drying, embedded energy in food and water and for shopping on line.
As an example, a round trip plane ticket for two people to go back east where I have relatives would be about 4000 lbs of C02. However it is a start.