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Tesla Semi

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Re: Tesla Semi

#571

Earlier quoted context omitted.

Like my fist has the power of a supernova explosion?

Is your fist's energy not a derivative of the big bang itself? Where did you think your fist got its energy from? Supernova would be underestimating the power of your fist. Truly think about the history of the energy of your system!

YES!

Re: Tesla Semi

#573

Earlier quoted context omitted.

There will always be situations where you can no longer recover energy, fully electric or hybrid. Your battery could be full, or overheating. At that point, you have to waste the energy. I believe the normal way to handle this scenario is to just fall back to mechanical braking.

Why do most/all electric and hybrid cars have regenerative braking while ICE cars don't? It's because, as the GP said, the battery would be quickly topped up and extra energy wasted. Only electric vehicles doing frequent stops/downhills can make productive use of regenerative braking. Potential energy lost by a truck going 10 m (vertically) downhill: 40 000 kg * g * 10 m = 4e6 J. Capacity of car starter battery: 40 A…

... Also because electric regenerative braking requires a battery and electric motor (for propulsion, the starter is useless for this). Once you fit regenerative braking into an ICE vehicle it becomes a hybrid vehicle, leaving no ICE vehicles with regenerative braking. :)

(I don't think you would call a vehicle with mechanical KERS system a "hybrid", although it technically is as there are multiple propulsion systems in the vehicle.)

Re: Tesla Semi

#574

Earlier quoted context omitted.

30 square meters, laying flat. So maybe 3kW. While the engines need more like 100kW. You can't effectively power any vehicle with 15% efficient solar panels.

One note, your second claim is not entirely true - while land vehicles are a ways from being feasible to power with photovoltaics (although I would have to do the math for trains, which may be close), we already have primarily [1] and exclusively [2] solar-powered aircraft. [1] https://en.wikipedia.org/wiki/Solar_Impulse#Solar_Impulse_2_... [2] https://en.wikipedia.org/wiki/Helios_Prototype

Those aircraft limp along at a tenth the speed of a typical commercial flight. That's the main reason I said "effectively". I mean, there are useless pure-solar cars too.

Trains might be closer but when single locomotives are measured in megawatts I'm not very confident.

Re: Tesla Semi

#575

Earlier quoted context omitted.

I often experience absurd impacts when I crash into reality.

Need to get yourself a bigger reality catcher on your grill.

Since installing airbags the problem has been lessened, but a reality catcher sounds like a great augmentation to my vehicle.
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