(theoretically) charging purely by regenerative breaking?

[Silverfish]

Lets say you lived in a zombie apocalypse, and had a wheel, and the only way you could charge it is by lugging it up some mountain or hill and riding it down. Does anyone have any rough idea of how much battery comes back over some distance at some downhill grade?

[Tawpie]

I have zero actual numbers, but my experience has been "not very much". True, if the hill is long and you come down fairly quickly (which means the hill is also steepish) you can raise the voltage of the pack a volt or two. But it's nothing to write home about.

[gon2fast]

The zombies would catch you walking/running up the hill before you got to a point where you could get a decent regenerative charge (I kid, I am sure you can run faster than decaying corpses, but you may have to trolley your wheel to keep your speed up LOL). 

As far as real world experience, if I do a big climb (3+ miles) I can burn up to 40% of my battery. The trip down usually results in a 15-20% return in charge.

[Silverfish]

I said zombies, but this originally started with the thought of wanting to see an updated max max with PEVs. A small gang of mad max style people pulling up to a car on EUCs would look pretty cool. And of course mad max is all about scarcity which got me thinking about the recharging. So I figured that this group would have to live at the base of a large hill or mountain and regularly hike it to charge their wheels. Maybe with slave labor to haul it up for them so they can ride it down. So I wondered how viable that would be. 

Of course, I'm no movie maker so I can't do anything with that anyway. But I do know how to make games, so who knows I might make a prototype of a post apocalypse wasteland PEV gang simulator.

[Hellkitten]

I just watched a video that @Marty Backeposted, where he was riding in the mountains of California. He was at 30% then rode down a fair bit of hill and ended up at 45%. I was surprised at how much he ended up with. Sorry I don’t have the link, but it’s on his channel. 

[itsmark]

Firstly you need to remember that voltage sags while under load. So if you ride up a steep hill for a few miles, check your battery level immediately, ride back down, and check you battery again and find that you have around 20% more life left then that 20% is probably more so from the fact that you aren't looking at the battery voltage while under load.

Secondly for the best post apocalyptic EUC-hill-charging-method you should rig find a ski lift/gondola near a stream/river. You can then construct a waterwheel powered by the stream/river that then powers the ski lift/gondola. This way you can ride up the lift up with your EUC and use the downhill to recharge your wheel.

[Menace]

3 hours ago, Silverfish said:

I said zombies, but this originally started with the thought of wanting to see an updated max max with PEVs. A small gang of mad max style people pulling up to a car on EUCs would look pretty cool. And of course mad max is all about scarcity which got me thinking about the recharging. So I figured that this group would have to live at the base of a large hill or mountain and regularly hike it to charge their wheels. Maybe with slave labor to haul it up for them so they can ride it down. So I wondered how viable that would be. 

Of course, I'm no movie maker so I can't do anything with that anyway. But I do know how to make games, so who knows I might make a prototype of a post apocalypse wasteland PEV gang simulator.

They could rig up some solar panels that they found, build a few diy wind turbines, use gas powered generators, and scavenge from car batteries (which they could raid, or just steal from crashed enemy vehicles). This should definitely be a movie.

[bracky72]

Strap it to a peloton and get to pedaling!

[MadVlad]

This is somewhat pointless because: humans are not very efficient at walking, we burn a lot of energy to produce very little forward progress. A bicycle is a simple mechanical device that significantly improves that efficiency. So yes, as bracky72 said, you would be better off connecting the thing to a stationary bicycle or rigging up a bicycle on a stand to drive the motor on the EUC and charge it that way. But even so, you are talking about a lot of calories that will be burned to do it. A much better setup would be a large solar panel or some sort of a wind/hydro setup (like a stream by your house), it may take longer, and it may not always be efficient, but it wont require you to burn calories.

[RockyTop]

Sorry man I have been working with the zombie to improve their efforts. … I felt sorry for them. Brains are so hard to find these days. 

 

Edited November 5, 2021 by RockyTop

[mike_bike_kite]

Great picture!

I'd heard that you can get back 30% of the energy you used by riding back down the hill. I think there's an optimum speed to do this regeneration as well. Most apps will show you power being generated or used. Your best bet in the zombie apocalypse might be some form of windmill to power the wheel (if it's windy where your bunker is) or solar panels (if it's sunny and your bunker isn't underground). Saying that, if you're basing your plans on surviving the zombie apocalypse around a unicycle then it might be better getting eaten in the first wave  

[newbie101]

I am newbie rider, with an MSP HT, I rode one of Marty’s Mt. baldy tour. I started with  100% battery, after about 23 miles up the Mt.  Baldy lodge, I had 50% left on my battery, so after coming down I end up with 36% battery. I would say I use less energy because of regeneration but I could not say you would gain more than what you have when you started going downhill.

Edited November 6, 2021 by newbie101

[TantasStarke]

It all depends on the length and grade of the hill, there's a hill I go down near my house for that's about a half mile and I can easily get -100Wh/mi going down, giving me like 2 miles of additional range

[Nostris]

Same here…I can never leave home with 100% battery, as the wheel will tell me to get off about 500 meters down the hill because of over charge. 

[Kekafuch]

I theorize that zombies are attracted to the human movement. You might be on to something about the EUC potentially being the best weapon against a major outbreak. If the theory pans out, the zombies may not pay any attention to a human riding the EUC amongst them. You just need to keep both feet on the pedals and have enough range ….