Posted on 08/18/2019 9:00:54 PM PDT by DUMBGRUNT
So, how many mines in the world are at the TOP of a mountain?
You would need to recharge the truck ! lol
Only if they take their three very fat aunts downhill and the come back home without them.
How much energy is used to fill the dump truck?
But it started with 100% charge in the first trip and back to the bottom with only 88%. That doesn’t look like a surplus to me. On each trip it will have less and less charge and eventually have to be recharged.
How are they doing over there with perpetual motion?
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Guess the author can't afford to be too picky.
“I’m guessing the writer was not a science major.”
I’m guessing he didn’t pass elementary school math or science.
You mean I no longer have to turn my car radio off to conserve electricity?
Actually there is a net loss of 12% of 100% charge on each trip so 8.333 trips equals dead battery. There ain’t no free lunch.
Yabba Dabba Do!
“eDumper”
No sir....not gonna comment on that, no matter how intriguing it sounds.
Good point, and it was one I first missed. If the truck actually produces more electricity than it consumes, it would always have 100% of capacity when it reaches the bottom. In fact, it would require resistive energy dumpers to prevent battery overcharging which would kill the batteries. Thus, it seems quite logically to me, that your math is correct: It takes up to 20% of capacity to go to the top, and only gains 8% back going down.
It seems likely to me that the problem is that the li-on batteries in the truck cannot be charged fast enough to utilize all of the available energy going down the hill. This is a typical problem with regenerative braking. In an automobile, the brakes can absorb thousands of horsepower in a hard stop, in a vehicle where the engine produces only hundreds of horsepower. Current technology batteries simply cannot be recharged at that rate. Thus regenerative braking doesn't reuse all of the available braking energy. I would guess that the truck has the same problem, and it is either missed, or ignored by the author.
In theory, any 110 ton downhill trip, followed by a 45 ton uphill trip, would only take a 41 percent efficiency powerplant to make a round trip for free. My guess is that the system is not 41 percent efficient.
Actually, the carbon footprint of the Gerald R. Ford is zero. It's nuclear powered. Just don't ask about the carbon footprint of the airships.
Someone invented a perpetual motion machine.
He was referring to the carbon footprint to build it.
Why all the cynicism here? I think this is a pretty ingenious way to perform a task in a very energy efficient manner. Understandably not practical for all uses but then that was never implied in the article either.
The cynicism is about the headline that never needs charging.
Great.
Don’t most quarries work the other way?
Talk about double talk:
“With more than double the weight going back down the hill, the beast’s regenerative braking system recaptures more than enough energy to refill the charge the eDumper used going up.”
Guess regenerating and/or refilling the charge isn’t the same as recharging. May work fine as long as there is a downhill section to work with. How well does it work on only uphill or level surfaces?
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