@samabuelsamid Would love your opinion on the tech used inside electric vehicles. Since they operate solely on batteries. Why do all makers seem to have pure digital dashboards. Some look like they have 15 inch tablets in the center. It seems to me that all this electricity used to power everything would be better used for driving range.
Not Sam, but I’ll chime in anyway.
All the power for all the screens is a rounding error compared to the propulsion.
At highway speeds in ideal conditions, a Tesla Model 3 will consume about 250 Watt-hours per mile, which is roughly equivalent to 15kW average power.
If we guess the dashboard and UI touchscreen might consumes 1% of the total power, that would be 150 watts. Let’s sanity check by comparing to an iPad:
The iPad Pro 12.9"has a 41 W-h battery. At 150W draw, that battery would have a discharge time of 17 minutes. Clearly the iPad lasts much longer (Apple claims 9-10 hours), so our 1% estimate is too high by a factor of at least 20x.
So it is reasonable to surmise the screens in a Model 3 consume much less than 1% of the total energy in the battery.
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I see this question a lot, cortex is right on.
Also keep in mind that most of the vehicle peripherals don’t draw directly from the powertrain battery, but rather the traditional 12v battery, which is in turn topped-up from the powertrain battery when necessary. On shorter trips where the vehicle is plugged in before and after, the peripherals may not even drain the powertrain battery.
Additionally, there isn’t very much dashboard information that can be collected without electronics in the pipeline in these vehicles. You could have a physical speedometer, but there is no tachometer, fluid pressure/temp, or fuel metric to measure. Critical vehicle metrics now include state-of-charge, and regen vs. power discharge, both things that cannot be measured through a physical interface and require a computer anyway.
I think it’s hard for us to understand just how much energy is expended when doing electronic work (powering a tablet, etc) vs physical work (moving a 5000lb vehicle). This video illustrates it pretty well - Olympic Cyclist Vs. Toaster: Can He Power It? - YouTube
There is one thing that does impact driving distance: heating and cooling. If you’re in a cold location (or time of year) and you’re using your heated seats a lot or the vehicle space heater (because there is no “free” combustion engine to bleed heat from) or you’re in a southerly climate (hello Arizona and Texas) and you’re using your air conditioning just to make the interior temps livable, then that is definitely going to impact the amount of distance you can drive.
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Thank you all for your insight on the subject. I always figured car makers would be trying to eek out every little mile per kilowatt. And I imagine heating and cooling would be a huge drain on the system.
I’m not sold on pure electric vehicles myself. Nothing wrong with those who love em. I like the idea of hybrids. Comforting to have a gas engine as a generator and backup power source at least to me.
I get that perspective, but the government is not in your favour. The laws outlawing “polluting” ICE vehicles will presumably apply equally to a hybrid that has a hydrocarbon based engine on board. Plus that engine is heavy, and will have a negative impact to your driving distance and [equivalent] fuel economy. An EV you can charge overnight at home will be fine for all your “around town” puttering. If you frequently road trip, then you just need to learn a new trick… there are apps that will help you plan your trip based on EV charging stations, and the 30 minutes to recharge to get back to 80%+ will provide convenient bathroom and food breaks.
Check out Mr. Technology Connections video about road-tripping in an EV. Reddit - Dive into anything
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They generally are interested in stretching range. But increasing the rated range of a car from 270 to 271 miles by eliminating a backlit display isn’t going to meaningfully change its market position.
And I’m doubtful the amount of power I discussed yesterday would result in even one additional mile.
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I saw the 8 bit guys journey to Midwest computer show. They took their Chevy bolt from Texas to Chicago. He used website to preplan where to charge up. Only added about 2 hours to his trip each day or so as opposed to filling up with gas. A totally doable trip.
As an EV owner I’m kinda with you on this. No doubt in my mind that electric motors are superior, but I don’t think we have the energy storage figured out yet. Chemical batteries are a stopgap, one which the industry has been pidgeon-holed into by a certain boisterous magnate… We’ll see what Toyota and SK can do with solid state battery tech.