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Comment by OliverJones | Hacker News Reader

Vehicle electronics have some real environmental challenges as well.

They have to function correctly

  * after they've been parked outdoors in Death Valley all day.

  * after they've been parked at -40 degrees for a long time.

  * when doused with slush containing road salt.

  * when their wiring harnesses deteriorate after a couple of decades of hard use.

  * at least for a few seconds after a catastrophic crash.

It takes the kind of risk-taking guts that Tesla exhibits to push new, better, electronic parts into test and production. Most car companies' executives, designers, and test engineers just don't want to take those risks.

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> risk-taking guts that Tesla exhibits to push new, better, electronic parts into test and production.

After their delaminationg non-automotive grade screens I'd be wary.

Their solution to it was to make the air conditioner always run in the sun when parked and promote it as a feature, wasting untold megawatt hours of electricity.

That sounds like possible death trap. Drive Tesla to some place without range, stay out there for week. Then come back an notice car is dead and you can't reach next charging station.

Maybe this is why Musk is making Starlink...

you can tow charge an electric car with another car or truck

I looked into this a few weeks ago while exploring purchasing an electric car, and from what I could find "tow charging" was experimented with but has basically been given up on. The expectation is that if you lose power, you will need a flatbed truck to cart the car to a charging station.

How do you order an other car or a truck if you can't make phone calls?

Charging efficiency isn't 100%, so you'd have to tow it further than the range you need. Seems like it'd make more sense to just tow it to a charger.

> Charging efficiency isn't 100%, so you'd have to tow it further than the range you need

That's not how it works. You basically get 5 mpg or less on the truck, while the car charges at significantly higher rates than the speed of the truck (in mph), because the car is more efficient at using the energy.

https://insideevs.com/news/514727/tesla-towing-70mph-fast-ch...

Towing at 70mph in the above example was charging the car at 65 kW. That's equivalent to ~260-270 mi/hr of charging rate assuming 250Wh/mi.

The comment you replied to is still correct though.

Distance wise, tow charging makes no sense. Energy wise, maybe it does.

If it makes sense energy wise, it makes sense distance wise too. If the EV can go 4 miles for every one mile towed, then why would it not make sense?

Ah I think I was tripped up by the same thing as the top commenter. This sounds like it violates the law of conservation of energy.

The key here is that when towing (as opposed to going downhill) you can put much more energy into the motor generators per mile than is required to drive a mile. Due to charge/discharge losses, for your example this would have to be > 4x the amount. This obviously assumes the EV can regen at high sustained rates and you have a powerful tow vehicle.

So yes, you're right. The energy/distance argument should be one and the same.

> It takes the kind of risk-taking guts that Tesla exhibits to push new, better, electronic parts into test and production.

Its not a risk if you are vertically integrated, have the software infrastructure and have everything need to do the needed testing and validation.

It would take weeks just to talk to the supplier about maybe doing a change for many other car makers.

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