Regenerative braking while hill climbing?

[Tesla]

Everyone has likely heard about this dump truck that never has to charge:

https://www.wired.com/story/this-huge-electric-dump-truck-never-needs-to-plug-in/

Has anyone been thinking about how well the Cybrtrk will regen while off-roading hills? I've seen the Engineering Explained about the Model S regen. But the truck will likely be a little heavier...

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[ModelAZ]

Hadn’t thought about this aspect but yea makes sense. With the Cybrtrk possibly weighing upwards of 7k lbs it should be able to reclaim a lot of energy when descending while off road.

 

[Snuups]

Offroad it's essential to regenerate on all four wheels. All other Tesla Regenerate on the rear wheels.

Can someone confirm that? I have 'heard' it is like that but iI never read any reliable source about this matter.

 

[bfayer]

With enough additional mass loaded at the top of a big hill, a rubber band powered truck will run forever.

The truck in the article is not so much "regenerative" as it is converting the potential energy of the load of rocks into electricity used to get back up the hill, empty.

 

[ajdelange]

Offroad it's essential to regenerate on all four wheels. All other Tesla Regenerate on the rear wheels.

It's pretty clear that one wants to apply or absorb equal torque to or from the left and right wheels in a pair (front pair or back pair) unless purposely torque vectoring in order to keep the vehicle running straight. Now when it comes to braking, be it with friction brakes or regenerative braking one wants to manage the relative torque absorbed at front and rear (and thus the relative weights on front and rear wheels) to maximize vehicle stability. That's just as important in a Tesla Model 3 as it will be in the CT and thus I do not believe that the other models do all regen at the rear axle motor.

Can someone confirm that? I have 'heard' it is like that but iI never read any reliable source about this matter.

I doubt it to be the case but only based on the reasoning in the first paragraph.

 

[ajdelange]

Has anyone been thinking about how well the Cybrtrk will regen while off-roading hills? I've seen the Engineering Explained about the Model S regen. But the truck will likely be a little heavier...

No but that's because I assume the CT will be about the same in its regen performance (i.e. able to recover about 3/4 of the energy expended against gravity and intertia).

If your job requires you you to haul rocks up a hill and return to the quarry empty you will visit the charging station often. If the quarry is at the top of the hill and your job is to delver them to a site at the bottom you will never visit the charger. It depends on the load - not the vehicle. I have ended trips in an X with more in the battery than was there when I set out (but it's pretty rare).

 

[ricinro]

No but that's because I assume the CT will be about the same in its regen performance (i.e. able to recover about 3/4 of the energy expended against gravity and intertia).

If your job requires you you to haul rocks up a hill and return to the quarry empty you will visit the charging station often. If the quarry is at the top of the hill and your job is to delver them to a site at the bottom you will never visit the charger. It depends on the load - not the vehicle. I have ended trips in an X with more in the battery than was there when I set out (but it's pretty rare).

I am reminded of something my dad told us about his childhood. He had to walk in the snow to school and back and both ways were uphill. We had it easy!

 

[ajdelange]

The comment was made based on recall of a story about an electric truck that has just this job. It is never charged. I had no idea where I saw this but stumbled on it again here recently. A search of the more recent posts might turn it up.

 

[ldjessee]

The comment was made based on recall of a story about and electric truck that has just this job. It is never charged. I had no idea where I saw this but stumbled on it again here recently. A search of the more recent posts might turn it up.

It is a German dump truck (rather large one) that takes heavy loads down the mountain, so charges up when taking this load down the mountain using regenerative charging... but since it is empty going back up, that means it takes much less energy and so easily makes it back up without needing to plugin and charge. It is actually a energy positive process.
This is a rare situation, but it makes so much sense given the situation.

Here is one of the many stories about the dump truck. https://www.popularmechanics.com/te...6/worlds-largest-electric-vehicle-dump-truck/

 

[ajdelange]

It's not really that rare at all. The totality of the electricity used by the province of Quebec and a large part of the electricity used in New York (which they buy from Quebec) is generated by this process. In Virginia they use excess production to pump water from a lower reservoir to a higher one and then let it run back down when demand is high. I saw a YouTube video in which a company had an experimental rig with a solar powered conveyer belt which carried pebbles up a hill during the day. At night the motors were turned into generators and he pebbles came back down the conveyer. What a kluge! I think they said the project was terminated because of noise.

 

[ldjessee]

It's not really that rare at all. The totality of the electricity used by the province of Quebec and a large part of the electricity used in New York (which they buy from Quebec) is generated by this process. In Virginia they use excess production to pump water from a lower reservoir to a higher one and then let it run back down when demand is high. I saw a YouTube video in which a company had an experimental rig with a solar powered conveyer belt which carried pebbles up a hill during the day. At night the motors were turned into generators and he pebbles came back down the conveyer. What a kluge! I think they said the project was terminated because of noise.

Pump hydro is pretty common and a known issue (also done in the Delaware Water Gap, which is between PA and NJ on the Delaware River), but you have to have the space and the elevation to do such... and if you need more capacity, you have to do some major terrain reshaping... assuming again you have the room to do it.
And the conveyer belt does sound like a kluge...
I am not even sure I like the stacked block concept. I do like the lowering and raising of the heavy weight down a mine shaft, as that seems much easier and easier to upgrade (go with a heavier weight and the equipment to handle it). It might even make sense to install the equipment to handle a heavier weight at first, then just add to the weight moved as needed.
http://euanmearns.com/short-term-energy-storage-with-gravitricity-iron-versus-ion/
(I am not a fan of the railroad car up the side of a hill/mountain)