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FS: Bike Power Generator - $200!

Description from http://www.windstreampower.com/Bike_Power_Generator.php


The average output of a person pedaling the Bike Power Generator is about 60-100 watts when connected to a load - usually a 12V Battery. Power output depends on the energy available from the person pedaling.

The generator we use can actually produce a maximum PEAK power output of around 275 Watts (13.6 V x 20A = 272W) for a few seconds when someone pedals with all their might. This is the nature of the peak power rating. It is more realistic however, to look at and ask about, what the average and sustainable power output is. This is the case with all pedal power generators on the market.


How long does it take to charge a 12V battery?


The quick answer is that it depends on the capacity of that battery and the resting voltage of that battery when you begin to charge it. Generally, the aH rating - or "amp hour" rating tells you what the capacity is. A car battery might have 200 aH but the battery in a portable power pack might only have 18 aH.


It takes less time to charge a 12V battery with low amp hours.


The quick formula is to divide the aH rating by the average amperes (current) you are producing. For example 18 aH divided by 6 amperes = 3 hours. This assumes a completely flat battery. If you battery is 50% or more full, it takes less time.


If you can produce 40 watts comfortably, then it's best to power devices that match your own output. If you plug an appliance into the power pack and it draws 300 watts to work, it will use up all of the stored power very quickly. Items like laptops, small dvd players, radios, lights and small electronics are good choices for human power because they require less power.


The Bike Power Generator consists of a powder coated steel trainer frame holding a high RPM permanent magnet DC generator. Your bicycle (typical adult 26-27 inch wheel diameter) is mounted securely to this frame and the rear tire is positioned to turn the friction drum that has been custom fit over the generator shaft. The amount of electrical power that can be generated by the Bike Power Generator is determined by the energy available from pedaling the bicycle. The stronger the user, the higher the production of electrical power. A well inflated tire with a smooth tread allows for maximum contact and efficiency.




demigod
2012-09-10 18:05:30

Link does not seem to work. What condition is it in? And why are you selling it?


2012-09-10 18:43:09

Try this www.windstreampower.com , and go to bike power generator. It is in great condition and I am selling it because I need to build a set of wheels for CX season and need to sacrifice something.


demigod
2012-09-10 21:20:19

Sold! thanks.


demigod
2012-09-16 21:05:16

The bike generator is now part of the insipid infrastructure for my largely fnatasy idea of a Bike Busker band. Along with a 12 volt battery-powered amp.


Maybe next Year!


(The schedule calls for the band to have it's debut at the opening of the Sandcasle sectiojn of the GAP. I*'m hoping it's during this century.)


mick
2012-09-17 18:28:33

Dude, I'll totally pull the trailer with you playing an electric guitar on the back


sgtjonson
2012-09-17 18:35:40

Hm, inspired bi Mick. Question for Flocks. Do we know power necessary for big white box?


2012-09-17 18:35:46

I'm pretty sure it would be hard to set this generator up on a moving bike.


You stop, hitch you back wheel into the thing, then you can get power.


There might be a way to get it to work on a moving bike, but


1) I dont' have that way (maybe I should talk to Nick).

2) Generating electric power, plus moving the bike forward is a lot of energy output.


I think a large racer probably could keep up with Flock and generate power, but it wouldn't be easy.


mick
2012-09-17 19:36:07

Hmmm. Yeah, that would be a question for Nick D, but he is currently on the road to Interbike. I know the thing has a huge battery.


Mick is right in that it would be a pretty herculean task to pull that trailer with the additional drag of a generator. It would be pretty cool to be able to use something like this to charge the trailer before a ride, though


2012-09-17 19:41:22

Double your pleasure, double your fun, double your posts for no good reason.


reddan
2012-09-17 19:52:04

I wonder if you could trickle-charge the battery while rolling by using a bottle dynamo or two? When you don't want the resistance, just pivot the dynamo away from the tire.


reddan
2012-09-17 19:52:04

Or something like a bottle generator that you could engage from the saddle on downhills, for a little braking assist. "Degenerative" braking, I suppose.


edmonds59
2012-09-17 20:00:39

Well, if it required only 30 Watt then it's doable. Since a lot of people could sustain 90 Watt for an hour or two without problem. And Flock ride usually not that hilly.


In regards of bottle generator -- I kinda don't like them for this purpose. I was thinking about hub generator. But I don't have specification either. but even with bottle generator we can spread batteries among participants to charge and then combine switch drained battery with recharged and repeat the operation.


2012-09-17 20:07:53

Hm,


SRAM SRAM i-Light Dynamo 730F Hub 3W32 HQR Silver Disc -- 6V, 2.4-3W.


Battery should be pretty small in terms of capacity if we want them to charge in 1 hour.


http://www.bikequarterly.com/VBQgenerator.pdf


So Efficiency about 50-66% (for hub or bottle dynamo) that means one needs to spend twice as much energy, i.e. for 30W system around we are talking around 50-60W. A little bit more serious efforts.


2012-09-17 20:21:08

How about a tandem bike with captain and stoker drivetrains separate. Captain powers bike, and stoker powers generator. I imagine you would get quite a few looks at red lights with the stoker pedaling like mad and the bike not going anywhere.


marko82
2012-09-17 23:42:00

I thought about it and I don't like it :) I would say tandem pulling cart and the third rider on the cart pedaling like mad. Then you spread a weight of the third one between two.


2012-09-18 19:45:51

Hm, if we put a third person on a cart then stationary bike generators look more attractive:

http://compare.ebay.com/like/300706233275?var=lv<yp=AllFixedPriceItemTypes&var=sbar


http://www.amazon.com/Bicycle-Generator-Watts-Pedal-Dynamo/dp/B003GJL6GO


http://www.amazon.com/gp/product/B002QLCWDY/ref=as_li_ss_tl?ie=UTF8&tag=freewaresharew01&linkCode=as2&camp=1789&creative=390957&creativeASIN=B002QLCWDY -- a little bit too expensive.


http://www.youtube.com/watch?v=R_-wVuEkk2E

http://www.youtube.com/watch?NR=1&v=kVAZIDFMRXY&feature=fvwp


2012-09-18 20:06:19

@Mikhail,


Mine setup looks more like the second than the first. But mine you just hook the bike into the stand, and push a lever that puts the tire onto the shaft for the generator.


I will need top use some setup to keep the voltage in range - probably a rechargeable battery.


I might even have to end up using an inverter to change the DC into 112 volt AC. Then if I use my batterypowered amp, I'd need to plug a wallwart into the inverted to power the amp. Seems a little convoluted to me, but it might be the way to go.


Before this all becomes practical, I might need tome serious wireheading help. At least soem consideratioin of options.


I do not envision ever using this set up for power when moving.


PS fun with pedal power:

http://www.youtube.com/watch_popup?v=yEH4Yum4nN4


mick
2012-09-18 22:57:40