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Comment by thewarrior | Hacker News Reader

Good thing we aren’t doing anything to destabilize a climate system that’s not causing us too much trouble as of now.

You mean, like manufacturing electronics? It takes about 1MWh to manufacture a laptop, the same energy needed to drive a Tesla for 3000 miles.

https://www.networkworld.com/article/2229029/computer-factor...

also lots of purified water

It’s all interconnected and inter causal in a gigantic mess.

> the same energy needed to drive a Tesla

who are the memeticists driving this analagy into our collective consciousness? why is this popularizing? ive been seeing this crop up more and more frequently.

it feels a bit like begging the question, except the arguer also holds TSLA

It's just a handy reference for energy usage, and I assume this figure is more readily available due to the car being battery powered. It's a bit harder to work out for an ICE-powered car, as you'd have to calculate the energy required to move the car based on aerodynamics and weight. I have no interest in TSLA stock, nor do I think Tesla is anything like the sustainable future of transportation. I mostly picked Telsa because it's Hacker News.

As you insist though, it's about the energy required to cycle 100,000 miles.

You can do exactly the same back-of-the-envelope calculation for ICE engines as you did for the Tesla, you just need to know the average fuel consumption per mile and the energy density of gasoline. No need to worry about areodynamics.

I was using that number to represent just the energy required to motivate the car, and assuming that an EV has near-perfect energy translation from battery to movement (and therefore providing an accurate enough representation of that energy). It gets a little complicated if you want to consider the fuel input, as you start getting into wells-to-wheels calculations. Depending on your power grid energy mix, it also makes things quite a bit worse for EVs.

Actually you already have something like this. MPGe is used across EV and ICE vehicles alike.

Fuel is far more energy dense for ICE engines are far far less efficient.

I don't get this comparison point as well, electronics is dwarfed compared to other far more energy intensive industries.

You can, but that wasn't the point I was making. My only point was that it takes around 300Wh/mile to move a car about the size and shape of a Tesla, regardless of how you power it. I won't use the example of Tesla next time, as it seems to confuse matters.

MPGe also touches on the source of the energy you are using to propel your car, and depending on your power grid energy mix, can produce quite widely different results for EVs. Once you also take into account transmission and conversion losses, it is not as good as you'd think.

Electronics is one of the most energy intensive industries in the world, especially if you do the calulcation per weight of final product.

So probably 10MWh to build a Tesla, before even driving it?

Nearer 25MWh, and that's just for the battery pack.

https://www.sciencedirect.com/science/article/abs/pii/S00078...

Also, just for fun, the embodied energy of a 1960's Fiat 500 (assuming its entire 500kg weight is made of steel, which is probably a good enough approximation) is 3MWh, or three laptops.

So what is more sustainable?

An electric bike?

You're not wrong. However, every time I think about that, I just tell myself to pedal harder ;)

just for reference 1kg of aluminum raw material,not alloy, not processed, not packed, not transported - just mined is over 40KWh.

In that regard even the raw materials for the car are orders of magnitude over.

Indeed. The embodied energy of the items we use every day is so under-appreciated, probably because we have outsourced the production of almost all of them to countries that have no problem burning oil and coal in the process.

Really, if we actually wanted to make motoring sustainable, we would all be driving a 60's era Fiat 500 or Honda C50 moped. They cost very little to make, in every way, are very fuel effecient (even with their very old engine designs), and discourage long journeys.

That won't work though, because there's too much money to be made from EVs.

Is there anything wrong with that? If people want EVs that's better than people wanting modern gas guzzlers.

Yes. People are not being given a choice (at least, here in the UK). Petrol cars are being legislated out of existence. Ideally, I want a reliable, cost-effective family car without any extra gadgets, and I don't want an EV. However, those cars are just not made any more.

Also, I doubt the people that want a gas guzzler will be among the first to switch to an EV.

I have a hybrid (so it can be charged home, for 3000km we used only 50L of gasoline) - the EV drive is amazing, (if not spooky) - silent start, no noise, no vibrations (of course no exhaust), so it's great for city drive. For longer haul - there is the gasoline. For added benefit the total power of both engines engaged is quite impressive, along with acceleration.

Until there is a massive network that can reliably charge on the go, gasoline is there to stay. Also flip note: I know Norway loves EV (due to tons of tax breaks), yet EV do suck at lower temps (say below -10C)

Since we're trying to use human-understandable units for measuring energy inputs, It's also the same amount of energy that is necessary to boil 600 pots of soup.

That's almost as much soup as I eat in a year.

Not much use unless you specify the size of the pot ;)

By my calculation, 1MWh is enough to boil 600 17-liter pots, which isn't very human-relatable.

We're talking about the full energy budget of common household objects, like laptops, so you need to take into account the inefficiency of your gas stove, as well as the full energy cost of extracting and transporting the natural gas to your apartment.

Well then, let's see your working. Gas is really quite efficient in all ways.

You can avoid a lot of flying and driving by using zoom on that laptop.

Yeah but flying is more fun.

- Sent from the Seattle Airport

Now take a look at all your other laptop-like gadgets (the infotainment in your car, your smartphone(s), TV(s), PC, gaming rig, etc etc), and tell me how much flying and driving they prevent.

Did you account for how much energy to create the Tesla as well?

No, I was just using it as a easily-understood reference of comparative energy usage. Really, it's about the same value for any other car with the same aerodynamics and weight as the Tesla.

As you point out, it gets a lot more complicated when you start adding up how much energy it takes to make a Tesla (or any other EV).

Really, if we actually wanted to make motoring sustainable, we would all be driving 60's era Fiat 500s or Honda C50 mopeds. They cost very little to make, in every way, are very fuel effecient (even with their very old engine designs), and discourage long journeys.

That won't work though, because there's too much money to be made from EVs.

What about energy expended manufacturing the Tesla?

I really regret using the example of a Tesla, as it conflates too many issues. I meant that it takes around 300Wh to move a car about the weight and shape of a Tesla, one mile.

It is a very interesting calculation to look at the energy cost of manufacturing any EV, and how long it takes to "pay it back" compared to an ICE-powered car, and under various sources of power for the electrical grid used to charge it. However, that was supposed to be beyond the scope of this conversation.

I drive more than 3000 miles per year and I've got this laptop for 4 years now.

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