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[TheRan]

It doesn't even need to be going down a hill, you could be on perfectly flat ground and still be regaining energy, as long as you need to slow down at some point.

[Crissa]

If you were taking a trip, which took 100% of your energy...  Say you lost 10% to your stops.

...Then adding regen could reclaim that 10% energy so you could spend it again.

It's not 'making new energy' it's letting you spend energy twice.

That's the same way GDP is counted:  GDP isn't the total number of dollars in the economy, it's the number of dollars spent.  Many of those dollars were spent many times, and so were counted over and over.

Same with regen.

Sure, you can't spend more than 100% of the initial energy.  Except, if you get to spend some of it twice, instead of losing it, you literally do spend more than 100% of the initial energy.

-Crissa

[talon]

TheRan, your last statement was qualified by the "as long as you need to slow down" and is correct.

I think we are practically in agreement Crissa. We all seem to have an okay understanding of how regen works it's just the semantics.

That's just it, reusing what would be lost does not mean it is over 100% of *initial* energy.
My problems are the words initial and spend.

Ideal example:  If you place a 1kg ball on the side of a hill 10 meters up, it has 98 Joules stored of initial total potential energy due to gravity. If it rolls down that hill and then goes up and then down repeatedly on a series of shorter hills, finally rolling forever on level ground at height 0 meters for this reference frame, it has not "used" (converted) more than a net of 98 Joules into kinetic energy. If it technically converted that 98 Joules of potential energy into kinetic energy and back 10 times, saying something like "~400 Joules was converted into kinetic energy" alone is very misleading and not very helpful. Think of the potential energy as battery charge. Starting with 10kWh, spending 5kWh, regenerating 2kWh, then spending 7kWh so you are now empty--you've spent 12kWh but only used 10kWh of the initial energy. Saying you've spent 12kWh can seemingly imply you can "go 12kWh's worth far"..

[Curt]

A 14.4KWh motorcycle with regen is more efficient and can go further than a 14.4KWh motorcycle without regen. Neither cumulatively expends any amount over 14.4KWh. That does. not. happen. Not in this universe.

In order to be able to regen some amount, many times that amount must necessarily have been spent earlier on building potential energy.

Edit: posted simultaneous with talons good explanation

[Crissa]

Getting to reuse energy literally does mean 'total energy spent' is higher than the initial energy capacity.

Yes.  In this universe.

-Crissa

[talon]

I keep racking my brain going through different examples to pick a side in this when both have merits.

If you spend $100 to make $1000 you have both made $900 (net), and made $1000 (at one point).

Remove the part in parentheses and you don't tell the whole story so either statement isn't as accurate.  So I lean towards the most obvious assumptions (the [net of] $900 imo). I'd assume if someone told me they made $1000 that it was a net in that reference frame, but perhaps they omit the $100 loss in their system.

You need an exhaustive amount of qualifiers added to your statements to communicate effectively, but that doesn't mean you are correct or incorrect without them... I think.

Sam, great video as always. It inspired me to do my range test, and I always am hungry for more cool EV content.

[TheRan]

A 14.4KWh motorcycle with regen is more efficient and can go further than a 14.4KWh motorcycle without regen. Neither cumulatively expends any amount over 14.4KWh. That does. not. happen. Not in this universe.

In order to be able to regen some amount, many times that amount must necessarily have been spent earlier on building potential energy.

Edit: posted simultaneous with talons good explanation

Sure, but without regen that potential energy would have been wasted as heat during braking. Regen captures some of that energy and puts it back into the battery. It charges the battery, no different to if you stopped off at a charging station to top up. Thus, the battery can put out over 100% of its total capacity during the trip.

For arguments sake lets substitute regen for a solar charger, the end result is the same. If you rode about with a solar panel strapped to your back and hooked up to a charger connected to the bike, and during your trip it recharged the battery just a little bit (or delayed the discharge, however you want to think about it), would you agree that you'd get more than 100% of the total capacity of the battery's worth of energy from the bike? No regen, so you're still wasting that potential energy as heat in the brakes (because slowing down is inevitable) but you're instead replacing it with solar energy.

[Richard230]

All I can say is that given a choice, I would rather convert slowing down when braking into electrons rather than into heat.   

[Curt]

Regen captures some of that energy and puts it back into the battery. It charges the battery, no different to if you stopped off at a charging station to top up. Thus, the battery can put out over 100% of its total capacity during the trip.

A charging station is different. A solar backpack is different. Adding weight at the top of a hill is different. All those things really do add energy to the bike, and cannot be counted as initial energy capacity.

When you apply regen, you can get no energy "back" unless you've already spent the energy up front, and quite a bit more because regen is inefficient.

Getting to reuse energy literally does mean 'total energy spent' is higher than the initial energy capacity.

Energy is never "re-used", only converted between electrical potential, kinetic, and gravitational potential.

If I give you $1000 and you give it back, and I give you $1000 again and you give it back, have I given you $2000? The money appears to have been re-used. But wouldn't that be a highly superficial way of looking at it?

[TheRan]

A charging station is different. A solar backpack is different. Adding weight at the top of a hill is different. All those things really do add energy to the bike, and cannot be counted as initial energy capacity.

When you apply regen, you can get no energy "back" unless you've already spent the energy up front, and quite a bit more because regen is inefficient.

How are they different? They're adding energy to the battery, same as regen. One gets that energy from a power plant, one gets it from the sun, and one gets it from slowing the bike down. Where it comes from makes no difference, assuming that the bike needs to slow down with the brakes in the case of regen (which will be the case in all real world journeys).

Saying that regen requires energy to be spent in order to regain it is a meaningless strawman argument, you're not expending any additional energy compared to if you didn't use regen.

Energy is never "re-used", only converted between electrical potential, kinetic, and gravitational potential.

If I give you $1000 and you give it back, and I give you $1000 again and you give it back, have I given you $2000? The money appears to have been re-used. But wouldn't that be a highly superficial way of looking at it?

It's not about how much money is left at the end, it's how much money has been moved in transactions. You're "expending" $1000, "regenning" $1000 (obviously less in the real world), and then "expending" an additional $1000. In total you've "expended" $2000. And yes if you can convert electrical energy to kinetic and then convert that kinetic energy back into electrical energy you can indeed reuse (some of) it.

[Crilly]

There is no free energy.  Except the sun.

[Crissa]

It's not free, but it's energy that's produced instead of brake dust, so it might as well be a negative total cost per watt.

-Crissa

[ESokoloff]

All I can say is that given a choice, I would rather convert slowing down when braking into electrons rather than into heat.   

This is my thought as well. 
I’ve configured my Custom settings for full coast when off the rheostat & full regen when the brake is applied. 
I feel it’s more efficient to coast then to attempt energy recuperation via regen when off the rheostat. 

[Crissa]

I found 100% braking regen to lock up the rear a little too easily.  So I'm doing 30-60 throttle-brake.

-Crissa

[JaimeC]

I'm starting to see the "Regen Argument" amongst e-Bikers in the same light as "the best motor oil" argument amongst ICE bikers...