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Comment by jcelerier | Hacker News Reader

> The average American, for example, uses the equivalent of 4 kW of motor fuels continuously

how is that possible ? I have a normal house with a few appliances turned on, plus three fairly powerful computers and some musical gear and I'm at 530VA right now according to my home's electricity meter

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Have you ever purchased anything from a store? How did that good get to the store?

Have you ever purchased anything online for home delivery? How did that good get to the delivery center, then your home?

Just because you didn’t pump a gallon of gas into your personally owned tank doesn’t mean it wasn’t burned on your behalf.

but surely that is already accounted for in another budget line right ? if you are just dividing total kwh of a country by households it does not make any sense as it would also count military stuff, etc.

But how do you move yourself from place to place?

Note that it's not necessary for you to personally burn the three gallons of fuel per day. It's an average.

I drive on average 8k kilometers per year. I doubt that this is amounting to all the rest, is it ?

a quick computation gives me, given that my car drinks roughly 7 liters of diesel / 100km if i'm not careful:

- 560 liters of diesel / year

- a liter of diesel is apparently ~10.74 kwh -> 6014 kwh total

- 6014 / 365 -> 16 kwh a day ? I don't see how this is making me any closer to 4000 kwh per day.

By your metric ways I see you might not be an American. However, you can readily divide the total motor fuel consumption in the US by the population in the US, and use your figure of energy per liter (which is a bit higher than pertrol, but it doesn't matter).

The point is that the global emissions story boils down to transport fuels, meat, leaky houses, and a long tail of irrelevant things, such as your choice of programming language at small scale.

At large scale the economic incentives alone are enough to encourage huge energy consumers to use a decent language (for example, Google and C++). But the whole information industry taken together is irrelevant to the global emissions story as long as we have an airline industry, cars, and hamburgers.

US Department of Transporation says the avg. American drives 13.5k miles per year.

Using an average mpg of 21.5 mpg (if the average age of a car is 12 years), this comes to ~628 gallons of gas per year.

EPA uses 33.7 kWh per gallon for ~21,160 kWh in a year. Divide by 360 * 24 and you get 2.5 kW continuous, so it seems plausible.

EU numbers based on [1] come out to ~1 kW for driving?

[1] https://www.odyssee-mure.eu/publications/efficiency-by-secto...

> 21.5 mpg

this is more than 11L/100 - I don't know anyone who has a car that consumes that much.

The Ford F-150 is the highest-selling vehicle in North America.

Also worth noting - the US gallon is smaller than the UK one. And anecdotally, the mileage rating in the US actually tends to represent real-world consumption, whereas the EU test - until very recently - did not.

Fair - I don't own a car myself, but the US DOT reports 24.4 mpg in 2018 for cars, SUVs, vans, and light trucks shorter than 121 inches. (This is an estimate of vehicles on the road, not 2018 model year.)

If we use a 2020 model year for passenger cars of ~40mpg and a more conservative 11,500 miles per year, it comes out to 1.1kW.

> light trucks shorter than 121 inches.

This definition excludes the best-selling vehicle.

I don’t know if the 4kW statistic is right but 16kWh per day is 0.667kW continuous (16kW / 24 hours).They specifically say not including electricity use but could see that continuous number climbing closer to the 4kW number if it did.

People who regularly fly would also likely quickly make this number rise.

4 kW continuous is 48 kWh per day. 4 kW * 24 h.

My bad, that's much closer.

Umm... I messed up the math. It's 96 kWh. There's enough embarrassment to go around it seems!

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