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Environment & Energy

progree

(13,028 posts)

10. It only works because it is moving mass from a higher elevation to a lower one

Reply to abqtommy (Reply #8)

Sun Aug 25, 2019, 10:19 PM

Aug 2019

thus capturing the change in potential energy of a mass going from higher elevation to a lower one.

It is an empty 45 ton truck going uphill, and a 110 ton truck (including the ore) going downhill.

If it had to move 110 tons uphill, it will take a lot of energy to do that -- more than the energy captured by the regenerative braking in moving that same mass downhill because of losses caused by friction and because of less-than-100% conversion efficiency.

Won't work to haul the big mass up and down and up and down etc.. (or down and up and down and up etc.) unless the ending point is lower in elevation than the starting point -- lower enough to make up for the friction and conversion losses.

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WTH? 110-ton electric vehicle dump truck never needs recharging. [View all] ffr Aug 2019 OP

This is outstanding. onecaliberal Aug 2019 #1

When Formula One began using K.E.R.S. House of Roberts Aug 2019 #2

Meanwhile, the US wants to bring back coal... hlthe2b Aug 2019 #3

I'm pretty sure that these would work just fine in an open pit strip mine. Cleetus Ford Aug 2019 #5

This message was self-deleted by its author hlthe2b Aug 2019 #6

Cheap coal is unaffordable. Coal at any price is unaffordable. marble falls Aug 2019 #7

Nicely stated packman Aug 2019 #13

what if it is not going up and down hills? pangaia Aug 2019 #4

Not to worry! If it's hauling out of a mine or quarry then abqtommy Aug 2019 #8

Ha Ha,, Shows you how much I know... pangaia Aug 2019 #9

It only works because it is moving mass from a higher elevation to a lower one progree Aug 2019 #10

Or to say it more correctly, it works because of the type of work that the truck does. ffr Aug 2019 #11

I was responding to the comments that I replied to, not to your OP progree Aug 2019 #12

Wow! A perpetual motion machine! NNadir Aug 2019 #14

A perpetual motion machine would work with no external energy inputs jmowreader Aug 2019 #15

So it's only used once? NNadir Aug 2019 #16

Not at all jmowreader Aug 2019 #17

And it's propelled up the hill with zero mass? The truck loads itself with mass without energy? NNadir Aug 2019 #18

#10 explains it. There is no claim to being a perpetual motion machine -- though it would keep progree Aug 2019 #19

Well, congrats to the engineer who looked at this and justified the conversion captain queeg Aug 2019 #20

saving 11,000 to 22,000 gals of diesel fuel per year alone justifies it Hermit-The-Prog Aug 2019 #21

It's essentially being "recharged" by all the energy used to mine the ore NickB79 Aug 2019 #22