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Comment by unaindz | Hacker News Reader

The biggest problem with electricity is the batteries. Right now an EV pollutes more an ICE engine, the pollution is just moved to the power plants. But then you have to take into account the batteries. Making them pollutes a lot and they don't last forever.

We should be minimizing the use of cars instead.

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Fully agree on minimizing the use of cars. But I still wanted to do this computation to compare:

EPA says a gallon produces 8.8 kg CO2/gal tailpipe emissions [0]. A best-case sedan does about 50 mi/gal [1]. That's 17.6 kg CO2/100 mi for a best case sedan.

A Tesla Model 3 uses about 25 kWh/100 mi [2]. 1 kWh produces about 1 kg CO2 when produced in the dirtiest way (coal), but in the US it's currently about 0.4 kg CO2/kWh on average [4]. That gives you 10-25 kg CO2/100 mi.

So the best case ICE is better only if you are producing the electricity from coal (even gas power is better than ICE). The nice thing about EVs is that you can often charge them with the cleanest power (e.g. solar), but I'm not sure how common that optimization is.

[0]: https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-t... [1]: https://www.fueleconomy.gov/feg/findacar.shtml [2]: https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=46206 [3]: https://www.eia.gov/tools/faqs/faq.php?id=74&t=11 [4]: https://app.electricitymaps.com/zone/US/12mo/monthly

CO2 emissions from the gasoline does not account for the energy necessary to refine the oil to produce it. These days refineries use electricity for that so if that comes from a coal plant, it adds like 25% of CO2 emission. So the best sedan is pretty much equivalent in the carbon emission to Tesla when that car uses electricity from an old coal plant with 30% efficiency.

A statement like "EVs pollute more than ICE engines" needs substantiation.

Large power generation systems (even messy ones like coal) are tremendously more efficient per unit CO2 produced than a car engine[1]. You could make a case, though it's been proven wrong many times, that the production of the battery in an EV generates more waste than a comparable ICE vehicle.

https://www.cotes.com/blog/greenhouse-gas-emissions-from-ev-...

And electric motors are way more efficient than ICE motors that hardly reach 40% efficiency.

This is a common myth. Most of the pollution of a vehicle is in its use, both for EVs and ICE [0]. The average EV, even on the dirtiest fuel, still has much higher efficiency than the average ICE. On top of that, things are only going to get better:

- more of our electricity is coming from clean (renewable/nuclear) sources every year. We reached 40% in 2023. [1] Solar and wind are dominating fossil fuel in new generation. [2]

- we're evolving battery materials for cleaner batteries, and more new battery materials will be sourced from recycled batteries instead of new mining. (EVs are still so relatively new and batteries live long enough that we haven't yet reached that point).

0) https://www.epa.gov/greenvehicles/electric-vehicle-myths#Myt... 1) https://www.wri.org/insights/clean-energy-progress-united-st... 2) https://www.eia.gov/tools/faqs/faq.php?id=427&t=3

Commuter EVs are the rare kind of electric consumers that can efficiently absorb the unstable solar-generated electricity. Having your car charged while you're in the office during daytime can effectively be free in many places.

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