Range anxiety

[EatenByLimestone]

I was sitting in my truck today and a couple guys in their 20s got into a Tesla beside me. The car began to thump from a sound system in it. It surprised me, I’d never heard wooffers in a Tesla! I wonder how much they shorten the range of it. I know some ICE cars upgrade their alternator due to the draw of a sound system.

Honestly. I could see where a giant battery could help someone build a good system!

 

[begreen]

Looks like the average 12v car audio amp draws 10-30 amps. A powerful 1000w system can draw 80 amps. I would think at some point one would need a second 12 v battery and an awareness of the limit of the DC to DC inverter charging the 12v battery off of the main HV battery.

That said, I would think that the effect on range would be small.

 

[EbS-P]

I bet I could turn your head with the right song with my upgraded sound system that was an optional extra at time of purchase. It makes everything inside rattle. Ahhh Tesla.

Proof that range anxiety is way over blown if you drive a Tesla. My guess is the AC on a hot day draws more.

 

[woodgeek]

Say you're going 60 mph (average) on the HW, and have a usage of 350 Wh/mile (conservative).

That works out to 60 miles/hr *350 Watt.hr/mile = 21,000 Watts = 21 kW.

A 1000W sound system I bet uses 500W on a steady basis max, and would drop range by a few %.

And hearing by more than that.

 

[begreen]

How efficient is the DC to DC conversion off the main (400v?) battery?

 

[gzecc]

I just learned that EV's are on avg. 20% heavier than IC autos. Interesting.

 

[EbS-P]

I just learned that EV's are on avg. 20% heavier than IC autos. Interesting.

My model X is 6000 pounds. Model 3 is 4000. Honda accord is 3250. Batteries are heavy.

 

[DBoon]

Roughly speaking on average the efficiency is probably 95-97% going in (Level 2 charging from 240V outlet) and the power conversion inverter subsection efficiency coming out is probably 97-98% efficient and the motor efficiency (for a permanent magnet motor and not an AC induction motor) probabably about 95% efficient). Overall, almost 90% efficient. I may be off by a few percent, but no one could credibly claim that the overall efficiency would be only 70%, for instance.

 

[begreen]

Roughly speaking on average the efficiency is probably 95-97% going in (Level 2 charging from 240V outlet) and the power conversion inverter subsection efficiency coming out is probably 97-98% efficient and the motor efficiency (for a permanent magnet motor and not an AC induction motor) probabably about 95% efficient). Overall, almost 90% efficient. I may be off by a few percent, but no one could credibly claim that the overall efficiency would be only 70%, for instance.

I was thinking that the audio system is 12v and meant the DC to DC inverter efficiency that keeps the 12V battery charged.

 

[EbS-P]

I was thinking that the audio system is 12v and meant the DC to DC inverter efficiency that keeps the 12V battery charged.

It’s got to be pretty high. Remember all the computers are run off the 12v that’s at least 300W. The falcon doors are heavy those actuators are 12v too.

 

[woodgeek]

It’s got to be pretty high. Remember all the computers are run off the 12v that’s at least 300W. The falcon doors are heavy those actuators are 12v too.

I don't think my Bolt has 300W of computers in it. The third party self-driving rig I can get for it (that gets close to Tesla driving autonomy) runs on a smartphone chip.

I read the DC-DC is 90+% converting HV to 12V. And that jibes with my own usage of inverters to backfeed appliances and my house.

 

[begreen]

Motor Trend had an interesting comparison of 5 of their long range EV test vehicles during winter. It's a revealing look at some successes and issues as EVs cope with real world driving and the inconsistencies of charging networks.

https://www.motortrend.com/reviews/road-tripping-in-our-long-term-electric-test-cars/

 

[EbS-P]

Motor Trend had an interesting comparison of 5 of their long range EV test vehicles during winter. It's a revealing look at some successes and issues as EVs cope with real world driving and the inconsistencies of charging networks.

https://www.motortrend.com/reviews/road-tripping-in-our-long-term-electric-test-cars/

Why leave out a model 3 or Y?

 

[woodgeek]

Why leave out a model 3 or Y?

a.k.a. the most popular EVs in the US, by far.

 

[EbS-P]

a.k.a. the most popular EVs in the US, by far.

I have seen a real shift in the media’s reporting in the last 1-3 years. Maybe it’s the algorithms but I am finding it harder and harder to find fair coverage. Case in point here. How many news outlets reported last week that Tesla had to recall ALL of their cars for font size being to small on the break system warning light. Not one even said how much to small it was. Non event from my perspective.

 

[stoveliker]

If it was a non event, there would be no recall...

I agree it is a minor issue. But the fact that a major mfg has to recall all vehicles (due to, in all fairness, stupidity - as with all the innovation and brains at this mfg, it should not be so hard to read and follow some rules that others have no trouble following...?), carries an associated cost that warrants coverage imo. Moreover, I believe that all recalls (complete lineup or partial) are generally covered in the media - for the simple reason of informing the public through one more channel.

My $0.02

 

[begreen]

Why leave out a model 3 or Y?

Maybe because they have already done a lot of coverage and wanted to update on other vehicles. MT has a lot of Tesla reviews. Or maybe because the range was less?

https://www.motortrend.com/reviews/evs-with-the-best-real-world-range/

https://www.motortrend.com/news/2024-volvo-ex90-ev-suv-price-msrp/

https://www.motortrend.com/news/2024-tesla-model-3-highland-coty-review/