Making electricity by means of my old bike

[Renewable_energyguy]

TL;DR

I am turning my old bike into an electrical generator using a dc permanent magnet motor which will be connected by a chain to the pedals, the motor will be directly wired to an inverter which will allow me to use the power I make.

going off the summary I want some feedback and any opinion that may improve this project, please and thank you.

 

[anorlunda]

Welcome to PF.

Are you aware that such devices have been sold so long that your grandfather probably had one when he was a kid?

If you mean something more, then tell us how much power you expect to make.
Or just give us your definition of success for your project.

 

[Renewable_energyguy]

Well I have to build it but the motor I plan to use is

 

[256bits]

@Renewable_energyguy
As @anorlunda asked, "How much power do you expect to make?"

 

[Asymptotic]

Generator specs are too vague.

• "Up to 350W".
• "12V/24V" implies two windings which would be paralleled for 12V, and placed in series for 24V, but only two leads are brought out.
• It could be 12V is generated at xxx RPM, and 24V when operated at twice that speed, but ...
• no speed rating is on the label, nor in the eBay description.
• Shaft diameter is 8mm, and it comes with an 11 tooth sprocket, but no mention of chain pitch. Will this sprocket work with your bike chain, or will it be necessary to replace it for one that does?

Continuing with @anorlunda and @256bits, "How much power do you expect to make?"
350W is far into the right hand of the FTP bell curve. FTP ("Functional Threshold Power") is average sustained power in one hour.

https://www.cyclinganalytics.com/blog/2018/06/how-does-your-cycling-power-output-compare

What will the power be used for? If it'll be for lighting it may make more sense to stay in DC and charge a battery to drive LED lamps rather than converting it to AC with an inverter, and incur the efficiency loss (10%? 15%?).

 

[jrmichler]

Here's some more data on cycling power vs time for healthy and fit men:

It's from Bicycling Science, Third Edition, by David Gordon Wilson. Actual electricity delivered from a generator will be less because of generator efficiency.

The above data is also from people pedaling at their best efficiency RPM. Careful selection of gear ratio is necessary when driving a generator because pedaling efficiency varies with RPM. This book is a good read for anybody interested in human power from pedaling.

 

[sysprog]

Shades of Gilligan's Island ...

 

[berkeman]

Summary: I am turning my old bike into an electrical generator using a dc permanent magnet motor which will be connected by a chain to the pedals,

Welcome to the PF.

Can you post a picture of your bike? (use the Upload button in the Edit window to upload a JPG or PDF file) Does it have toe clips or stirrups on the pedals? What is your cycling background? How many miles a week do you currently ride? Do you ride hills, or mostly flat routes?

What is your electronics background? There are some combinations of bike gearing and power conversion electronics that will help you get the most out of your setup. Are you planning on using some of the power in real time (like running your laptop and charging your cellphone) while storing the extra energy in a deep-discharge battery?

Per the very helpful curves posted by @jrmichler you should shoot for about 200W power from you pedaling for about an hour. That's assuming that you already ride a good amount of miles per week on the roads.

 

[sysprog]

Welcome to the PF.

Can you post a picture of your bike? (use the Upload button in the Edit window to upload a JPG or PDF file) Does it have toe clips or stirrups on the pedals? What is your cycling background? How many miles a week do you currently ride? Do you ride hills, or mostly flat routes?

What is your electronics background? There are some combinations of bike gearing and power conversion electronics that will help you get the most out of your setup. Are you planning on using some of the power in real time (like running your laptop and charging your cellphone) while storing the extra energy in a deep-discharge battery?

Per the very helpful curves posted by @jrmichler you should shoot for about 200W power from you pedaling for about an hour. That's assuming that you already ride a good amount of miles per week on the roads.

Just to clarify a bit -- if @Renewable_energyguy generates 200w for an hour steadily, he gens 200wh during that hour; i.e. he gens 200wh/hr, so if he pedals continuously for multiple hours at that rate, and he wants to charge a 100ah 12v battery, he'll need 6 hours of pedaling to get it fully charged.

 

[anorlunda]

I tried a search for "bicycle powered generator" on Youtube.com There are very many videos of successful projects that the OP can learn from. Among them is this video that discusses how much energy is realistic to make by pedaling.