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[Crissa]

Mine coasts terribly.

Like I've said before, I can't get a good regen going on with more than a piddly 6% grade.

-Crissa

[mistasam]

Sorry everybody.. I think it's a miscommunication thing, or a problem with how I phrased it again.  Here's an example I probably shouldn't animate:

Let's say you drink 2 liters of water and then pee out 1 liter 

Then you drink that 1 liter of pee water.

The total amount of water that existed was always 2 liters, but you technically "drank 3 liters".

This is what I meant by "using more than 100% of your battery".. not that new energy was created from no where.  It's a matter of perspective.  You didn't create more water.. you just turned that water into pee.  And regen gives you the opportunity to drink it again 

[DonTom]

Sorry everybody.. I think it's a miscommunication thing, or a problem with how I phrased it again.  Here's an example I probably shouldn't animate:

Let's say you drink 2 liters of water and then pee out 1 liter 

Then you drink that 1 liter of pee water.

The total amount of water that existed was always 2 liters, but you technically "drank 3 liters".

This is what I meant by "using more than 100% of your battery".. not that new energy was created from no where.  It's a matter of perspective.

Here is another matter of perspective.

I would say it compares to having  10KWHs  worth of battery full, riding 50 miles   and stopping for a recharge of 5 KWH.  That's 15 KWH from  a ten KWH battery even if no regen!

Charging is charging, regardless if from regen or a charge station.  It's just that regen can give a little more charge without a stop & wait.

-Don-  Auburn, CA

[mistasam]

It's just that regen can give a little more charge without a stop & wait.

Yes!  I like that mentality.

[Curt]

(Un)fortunately, Bear Grylls already demonstrated it on a raft out in the ocean.

I think I can finally clarify by extending your urinalogy. Consider a space station with a 2,000 liter tank of water which is recycled 1, 000 times.

From the view of an outside observer (like the shuttle), 2,000 liters were delivered to the station, and they were used efficiently.

From the view of the astronauts, 2,000,000 liters came out of the faucet.

The two frames of reference are the origin of the two viewpoints. Both are important, as one would need to consider both when designing the system.

However, even the astronaut would never phrase it as "we got 2,000,000 liters out of a 2,000 liter tank," even if speaking to school children. It would make them dumber. That's what my objection comes down to.

[Crissa]

But Curt, that's literally how water recycling works.  You get n liters through the recycler, which is more than the size of the tank.

You're saying we can't say we get thousands of miles out of tires which are only two feet in diameter.

That's... Silly.

-Crissa

[mistasam]

Haha urinalogy 

Yeah that makes a lot of sense... except when it comes to hills. Ride to the top and there's no kinetic energy to keep you going, so you've used everything that battery had. Then the motor recharges it going down. In the case of that mining truck, it could recharge more than it used going up. How does that one work?

You're still turning one type of energy into another, but it doesn't seem to be energy that was originally in the battery.

[princec]

Mistasam's clarified description has now stopped his physics professor from spinning in his grave.
The only other factor is, of course, the potential energy of a mass starting out at the top of a hill, but my gut feeling is that if you can make it down the hill without braking at all, you're better off with the coast than attempting to scavenge a few watts from regen.

Cas

[Crissa]

...Which is in the video, Curt.

-Crissa

[mistasam]

So using 10kWh to get up the hill created the potential to generate and use 1 more kWh, right?

[princec]

Well, it didn't create the potential, it converted the kinetic energy into potential energy.

Cas

[TheRan]

It created potential energy from kinetic energy. There's nothing wrong with saying a certain type of energy is created as long as you say what it's created from, which Sam did. The issue comes when someone says energy can be created from nothing, which no-one in this discussion ever did but some people seem to think otherwise.