Eating less vs building electric cars

Posted on December 12, 2016

(Last Updated On: December 12, 2016)


Hey, that’s great. But it got me thinking…

In decreasing airline ticket prices through having less overweight people, it was shown we could save 1.32 billion gallons of gas if we (granted, waved a magic wand) had no overweight people / no overweight people flying. That’s per year.

Too far fetched you say.

-> Japan has a 3.5% obesity rate. One thing they do- have a mandate on waistline size. Controversial? In America? Oh christ yes. But magic wand waved?

Alright, how about this:

1 gallon of gasoline = 31,000 (kilo)calories

120 million gallons of gas = 3.7 trillion calories

That’s quite a bit of calories! What if we took America, a country with a population that certainly could go for eating less, and we asked for a pittance of 100 calories per day less eaten, per person.

320 million people * 100 calories per day per person * 365 days per year = 11.7 trillion calories per year

More than three times the calories saved by Tesla.

Or what if we get a group of people to eat, let’s go with one thousand less calories per day:

1,000 calories per day => 365,000 calories per year for that person

3.7 trillion calories / 365,000 calories per person = 10.1 million people

Sounds like a lot of people, but it’s only 3% of America.

Not to bash Tesla, I’m a fan, but their numbers are for their entire history. They’ve been around 14 years. They’ve had thousands of really smart people working by all accounts crazy hours, being led by perhaps the most heralded contemporary entrepreneur. But could their effort be superseded through something as basic as getting a population we already want / who already should be eating a lot less, to only eat a tad less?

It’s true saving calories from being eaten may not translate to less gallons of gasoline, and subsequently less greenhouse gas emissions, like an electric motor does. Let’s look into that.

How much CO2 does it take to produce a calorie?

In America there are,

  • 72.5 million healthy weight adults eating 1679 calories per day each
  • 83 million overweight adults eating 1869 calories per day each
  • 89.3 million obese adults eating 2177 calories per day each
  • 49 million healthy weight children eating 1758 calories per day each
  • 12.33 million overweight children eating 1924 calories per day each
  • 12.16 million obese children eating 2177 calories per day each
    • Can see where kcals come from here, though the adults have been updated above. Overweight / obese went from 66% to 70.4%


365 days per year  * ((72.5 million * 1679) + (83 million * 1869) + (89.3 million * 2177) + (49 million * 1758) + (12.33 million * 1924) + (12.16 million * 2177))


2.21 * 10^14 calories per year

In America, in 2014, agriculture accounted for 9% of greenhouse gas emissions, with 6,870 million metric tons total.

Giving us,

6,870 million metric tons * 0.09 = 618.3 million metric tons

= 1.36 * 10^12 lbs of CO2 equivalents from agriculture per year


1.36 * 10^12 lbs of CO2 equivalents from agriculture per year

/ 2.21 * 10^14 calories per year

= 0.0062 lbs of CO2 per calorie produced

For gasoline, it’s 19.64 pounds of CO2 per gallon of gas.

If Tesla saves 120 million gallons of gasoline, that’s 2.4 billion pounds of CO2 saved. This isn’t accurate right now, because not all electricity production is non-CO2 based. In fact, the majority of it is fossil fuel based, right now. That’ll change as / if solar and battery storage predominate, but let’s run with the ideal scenario.

To save that much CO2 in calories,

2.4 billion lbs CO2 = number of calories * 0.0062 lbs of CO2 per calorie produced

2.4 billion / 0.0062 = 3.9 * 10^11 calories


Between overweight and obese adults and kids, we have 197 million people in America who could easily lose weight.

3.9 * 10^11 calories / 197,000,000 people = 1980 kcals per person

Remember, Tesla has achieved their number after fourteen years of effort. If each overweight / obese person ate

1980 calories per person per year / 365 days per year = 5.4

less calories per day over the course of a year, then every year we’d match Tesla’s effort. Or if all the overweight / obese decided to fast for a day, that’s one single day, we’d also match Tesla’s IDEAL emissions reduction. Because really, and it will be this way for many years, Tesla is only hoping to save ~half the emissions of a gas car. Meaning we could more than halve our calorie intakes above…and be 14 times more effective than Tesla has been.

And that’s being generous! Because while we’ve lessened the emissions due to agriculture, we haven’t accounted for the emissions due to other things, like transportation. Bodies which weigh less directly save gallons of gas like electric cars can.

Again, I’m a fan of Tesla, but their tweet is how much gasoline they’ve saved, not how many emissions they’ve saved.

tesla-less-gas-announcement-120-million-gallons It could be coincidence, but the average miles per gallon of new cars in America is ~25.

3 billion miles / 25 miles per gallon = 120 million gallons

Believe that’s where their number is coming from. Meaning it does not account for where their electricity is coming from => it doesn’t account for how many emissions they’ve reduced. Because in many areas electric cars are still as dirty as gasoline cars, one could make an argument, in an emissions sense, their number above is meaningless.

Granted, Tesla’s numbers will jump as more electric cars get on the road, but the ability to save emissions through eating less will rise as well so long as people keep gaining weight.

Another rub? Tesla is an international company, while we’ve only looked at saving calories in America. If we look at all the countries Tesla has drivers in, at least 30 with one article I find stating America is only half the cars, then the amount of calories per person would be even less as we’d significantly increase our overweight / obese pool.

-> If we consider all the healthy weight people who are teetering on being overweight, we could then lessen the calorie numbers even more.

Tesla and others should of course keep going, but the rest of us needn’t wait for what is ultimately a small group of people to hopefully get us out of this risky experiment we’re running. A group of people that no matter how fast they work, can never build e.g. cars as quickly as we can e.g. start eating less. We all got us into this; we all need to, and can, help get out of it.

Personal trainers / dietitians: Tesla has 14,000 employees. They don’t only work on cars, Tesla also makes home battery packs, but cars is what this post is about. Their battery business is only a year old. Let’s say 12,000 of those employees are related to cars.

2.4 billion lbs CO2 / 12,000 employees = 200,000 lbs of CO2 saved per employee

That’s the ideal scenario. In reality, this number is more than halved, but let’s again run with the ideal.

200,000 lbs of CO2 / 0.0062 lbs of CO2 per calorie produced = 3.22 * 10^7 calories

I don’t know what the average clientele of a trainer / dietitian is, but it’s easily in the upper hundreds. 1,000 clients over the course of a 30 year career is 33 clients per year. Less than three clients per month. Sounds reasonable. That’s 467 clients after 14 years of work, but we’ll low ball it a good deal.

3.22 * 10^7 calories / 300 clients = 107,527 calories per client


107,527 calories per year / 365 days per year = 295 calories per day

Get these clients to cease an average of 295 calories per day, and from an emissions reduction standpoint you’re doing what a Tesla employee has done. 

Note this isn’t even curing overweightness. If we look back at our calories per weight class above, this is getting obese people to eat an overweight number of calories and overweight people to eat a healthy weight number.

Technology can do incredible things. So can mass amounts of people changing their behavior, which is possible. Particularly when it’s in self-interest, like improving our health and saving money.

Rise and fall of smoking

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