THE GLOBAL WARMING PUZZLE: HOW MANY PEOPLE DOES ONE CAR AMOUNT TO?

1. A world average of individual car usage is about 12,334 miles per year, which translates into (12,334 miles / 365 days) = 33.8 miles per day, or 54.4 kilometers per day.

2. A world average of gasoline mileage per car is 31.2 miles per gallon, which translates into 50.2 kilometers per gallon, or 13.3 kilometers per liter.

3. Therefore, the world average daily consumption of gasoline is:   (54.4 km/day) / (13.3 km/liter) = 4.09 liters per day per car.

4. The average density of gasoline is 0.74 kilogram per liter.

5. The world average daily consumption of gasoline, per car, is:   4.09 liters per day × 0.74 kilogram per liter = 3.027 kilograms per day per car, or 3,027 grams per day.

6. The average energy released by the burning of gasoline is 45.8 kilojoules per gram, or 10.95 kilocalories per gram.

7. The average global rate of gasoline energy consumption, per car, is:   (3,027 grams/day × 10.95 kilocalories per gram) = 33,146 kilocalories per day.

8. An average person weighs 62 kilograms.

9. To maintain his/her own weight, an average person needs 33 kilocalories per kilogram of body weight.

10. Therefore, a constant-weight average person consumes (62 kilograms × 33 kilocalories/kilogram) = 2,046 kilocalories per day.

11. Therefore, the ratio of vehicle-to-person energy consumption is:   (33,146 / 2,046) = 16.2.

12. In terms of energy consumption, one (1) car is equivalent to 16 persons.

13. There are approximately 8,037 billion people in the world today (November 2022).

14. At present (2022), there are approximately 1.446 billion cars in the world (2022).

15. The people in the world burn (8,037,000,000 × 2,046 kilocalories/day) = 16,444,000,000,000 kilocalories per day = 16,444 teracalories per day.

16. The vehicles in the world burn (1,446,000,000 × 33,146 kilocalories per day) = 47,929,000,000,000 kilocalories per day = 47,929 teracalories per day.

17. The total number of calories consumed daily by people and vehicles amounts to: (16,444 + 47,929) = 64,373 teracalories.

18. This is equivalent to: (64,373,000,000,000 kilocalories per day / 2,046 kilocalories/day/person) = 31,463,000,000 equivalent persons.

19. The ratio between equivalent persons to actual persons is: (31,463,000,000 / 8,037,000,000) = 3.91

20. Therefore, current use of fossil fuel [in car transportation] amounts to an equivalent population which is about four (4) times larger than the actual value, in terms of energy consumption and subsequent release of carbon dioxide to the atmosphere.

Note:   Values in items 1, 2, 13, and 14 are estimated averages, intended for reference only. Actual calculation will vary with usage or growth.

 Victor Miguel Ponce is emeritus professor of civil and environmental engineering at San Diego State University. His specialty is hydrology, hydraulics, environmental science, and sustainable development.

© 2007, 2013, 2020, 2022 Victor M. Ponce 221128