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Comment by altruios | Hacker News Reader

Fossil fuel and hydrogen sadly will not end (just be severely reduced - which is good)...

Semi-trucks are not good candidates for EV tech (yet)... high altitudes (or changing altitudes greatly during a trip) or cold weather affect battery capacity. Mountain people that need to go down to the city below them would not have a good experience with EVs.

For urban city dwelling people the biggest concern is being able to charge at home (so living in an apartment with street parking or no car spot makes having an EV difficult)... But more and more infrastructure is rolling out - so I expect most cars in cities to be EV's shortly...

It's sunsetting, the fossil fuel industry, but it won't go away completely until the needs of travel are covered completely by EV tech... Which is something we should be striving towards by recognizing (and eliminating/reducing) where EV's are not appropriate.

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EVs do better at high altitudes and altitude changes than combustion vehicles.

Combustion engines, especially naturally-aspirated ones, lose power at high altitudes due to lower air density for combustion.

Combustion vehicles spend just as much extra energy going uphill as EVs do, but that energy is not recouped on downhill sections.

EVs also get the benefit of not wearing mechanical brakes going downhill.

I drive my EV in mountains all the time with 5,000ft elevation changes without issue. Average travel speed (highways) matters more than elevation changes especially if your net elevation change is neutral over a round trip.

Why are high or changing altitudes problematic for EVs?

going up a hill requires more energy and puts a higher strain on the battery as it pulls more power (if that's a consistent part of your commute - then the battery health lowers faster).

Battery draw doesn't reduce lithium battery life. Starting power, especially in Tesla going fast, is way higher than hauling something up hill. Exceeding the max power would hurt the battery, but the batteries are protected. But going up hill wouldn't come close to that.

The main factor with lithium battery lifetime is charging cycles. Going up hill would drain the battery faster lead to be more charging, but it would be a small effect.

The other factor is heat. A quick acceleration doesn't have time to heat the batteries, but a long climb does.

I'd be more concerned about motor heat than battery heat. The battery should be very carefully climate-controlled, but the motors are more difficult.

In my expierence it’s not that significant. Also regen going down hill adds a lot of control, reduces brake wear, and recovers some of the energy spent going up.

In my experience it has been significant. going up the mountain from the base to crestline takes as much energy as going from riverside orange county (12 miles up a mountain vs ~50 miles on flat land). (both a fiat500e and bolt EUV for reference have about the same efficacy change)

Yeah but then when you go back down you get most of it back.

That's my experience with an EV, the regen is so good I'll gain back significant charge going down a mountain.

Right, but that's true in a combustion vehicle as well, and in the EV you regain energy on the downhill while a combustion vehicle at best continues to consume idle amounts of fuel and wears its brake pads.

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