Project! Pedal power bicycle generator, ghetto style

[MetroMPG]

Yup, the generator runs on the side of the tire. I want to leave the existing knobby tire on so the bike remains usable in short order.

So this afternoon I picked up a junk 12v battery.

And... it works! I can charge it with the bike.

Also, I've linked to the images in the thread instead of using attachments, so you don't need to be an EcoRenovator member to see them.

[aerohead]

Darin,have you seen HOME POWER Magazine? They do all kinda stuff and it's individuals,not business.They cobble up some of the neatest stuff for home and cars and I believe many parents have bicycle generators.It's the only way they'll let their kids watch TV.I think Ed Beagely Jr.(sp?)does this at home.

[MetroMPG]

Originally Posted by MetroMPG

Goal for this weekend is to recharge my camera batteries... WITH! MY! LEGS! Woo.

MISSION ACCOMPLISHED.

Posted a summary of my thoughts about this project in the ER thread, including the fact that I'm spinning that little motor/generator at over 7000 RPM to make useful power.

I'm going to shoot a bit of video of the setup with my, ahem, human powered camera.

[MetroMPG]

See the ghetto bikegen in action here.

[Christ]

nice.

[oldpecan]

metrompg, congrats on your progress

(I haven't seen your vid due to my really really slow and bad internet ISP - don't ask)

The particular issue of HOME POWER magazine with the article about the pedal-powered video-player + TV is the Feb/March issue of 2001. (So much for my estimate that it was 10+ years ago). the author is Aaron Dahlen.

You must subscribe to HOME POWER afaik to read it. He was fairly technical as to methods of buffering the varying human-power output to make it usable for the the narrow range of input required by the electronics

He addresses some of the complications of powering a IIRC cathode ray tube TV with a bicycle set-up, such as, that type of TV requires a very big, but momentary) start-up current to establish a magnetic field (anti-gauss IIRC). Perhaps LCD TV's don't suffer from that requirement.

anyway the author was a fit fellow in his late 20's IIRC, but found he had to build up his strength and stamina to power that set-up for the duration of an entire movie. IIRC he was providing the energy for a VCR and maybe a 25" TV. old school CRT TV IIRC.

hopefully DVD players use less power than VCR's and I'm pretty sure LCD's use noticeably less power than what he was powering.

[MetroMPG]

I was going to try watching a tv show while powering the (fully charged) laptop computer last evening, but my apartment neighbour came home. (I don't like to use the generator when she's home because it's a little noisy and the walls are thin.)

The laptop runs on 25 watts. Guesstimating 70% efficiency of the AC inverter, that's 36 watts I'd have to generate. Doable, even on this inefficient set-up.

But I have been using the generator, maybe 30 minutes a day in bits and pieces. I'm still recharging the used car battery I got. It arrived with 12.3 resting voltage. It's up around 12.5v resting now. Not sure what its capacity is...

[MetroMPG]

Never mind - I tried using the inverter to power the laptop (26w AC output), and it (inverter) kept cycling on & off, more or less in synch with the pedal stroke. No matter how hard I tried to keep the DMM showing a voltage between the operating range of the inverter, couldn't keep it on for very long.

With a lighter load on it (15w) it stayed on. I guess I need a capacitor or battery to smooth the pulses.

---

And here's the vid if you haven't seen it yet:

http://ca.youtube.com/watch?v=tzQiurfsypI

[JasonG]

May I suggest adding a diode to the circuit so you don't have to deal with the switch to prevent the motor from driving the wheel.
I believe it will improve the charge efficiency as well.

[G2TDI]

many times exercise bikes can be had for (next to) nothing on craigslist.