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Comment by RutZap | Hacker News Reader

I believe that driving an old car for longer has a smaller environmental impact than consistently driving newer cars as the bulk of emissions is during the manufacturing process. I have no data to support my statement, it's just my hunch. I'd be very keen if someone with the right knowledge can approve or disprove my statement.

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Not true at all, ~80% of emissions from an ICE car are from using and servicing it.

https://www.iea.org/data-and-statistics/charts/comparative-l...

Looking at that chart I think you could build a brand new ICE car, throw it away, build an EV and drive that instead and still come out ahead?

> Vehicle assumptions: 200 000 km lifetime mileage

I was under the impression decent quality ICE vehicles are proven to last at least 320k km these days, and can easily last 15+ years.

Have electric vehicles even been in use long enough to have sufficient data to compare?

"Easily"

At least for a snowy area, those numbers are probably on the high side for reliable transportation but not 2x on the high side.

Presumably, an EV would at least need a battery replacement well before that point.

I presume an EV would rust the same as an ICE due to road salt/ice melt.

Electric vehicles are far simpler mechanically, so I expect they will last much longer.

only if they have been built to do so.

the same busted (and hard to repair) body parts will occur in both. Think AC, window motors, lamps and switches, etc.

plus, none of the manufacturers seem to be investing in easily replaceable batteries. They'd rather you buy a new car. May as well right? the batt replacement is 60% of the cost!

If we take as given that "decent quality ICE vehicles are proven to last at least 320k km", then after accounting for both vehicles that are less than decent quality, and vehicles destroyed due to accident, malicious damage or poor maintenance long before they reach that figure, then a fleet average of 200,000 km doesn't seem out of the question.

The same factors would seem to apply to EVs (except perhaps poor maintenance, but I am not knowledgeable enough about EVs to be sure), so for the purposes of comparison, I figured apples to apples would be comparing expected lifetimes of both assuming they are not abused or neglected.

It seems to me that they are using an expected lifetime (in the "expected value" sense) of 200,000 km for both types of vehicles.

If those factors apply equally and dominate the reasons vehicles reach EOL, then the expected lifetime not varying significantly between the vehicle types looks like a reasonable assumption.

Using the real expected lifetime taking into account the circumstances that tend to render a vehicle permanently unserviceable in the real world looks like the correct approach to determine how manufacturing costs are amortised over the vehicle lifetime.

The opposite is true - the manufacturing process is responsible for an average of 7-10 tonnes of CO2, while the same vehicle over its lifetime will emit more than 50 tonnes from the exhaust.

Moreover manufacturers have been reducing their carbon footprint lately. As an example VW reports that 70% of the energy the use in plants is provided by renewable sources.

That being said while emissions rules have been getting more stringent over the years, they're increasingly being followed through introducing EVs, not improvements in engine efficiency.

> As an example VW reports that 70% of the energy the use in plants is provided by renewable sources.

This is a great start, but not where most of the carbon embodied in a new vehicle comes from. The energy used by the VW plants keeps the lights on, air conditioned, and powers tools for assembly. Most of the carbon embodied in a car comes from the energy it takes to mine raw materials and process them into useful metals.

This seems to be the crucial bit that is always missing from these discussions. I don't doubt that the CO2 emitted in the assembly of the car is less than in the driving. But I'm curious about all the other environmental impacts (of which CO2 is just one small bit). The destruction of wildlife habitat, the poisoning of ground water, etc, that's involved in the retrieval and processing of the raw materials, on up through the chain.

> Most of the carbon embodied in a car comes from the energy it takes to mine raw materials and process them into useful metals.

Yes, and that is included in this estimate.

Producing a tonne of steel emits 1.85t of CO2. The estimate for mining and processing is "just" 270kg/t:

https://www.researchgate.net/publication/324486263_Analysis_...

This pales in comparison to the 20 tonnes of fuel a typical car is going to work itself through throughout its lifetime. And all this fuel has to be first extracted and refined.

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