How To Build A Bicycle Generator

The intention of this project is to build a straight forward human powered generator from a used bicycle and to use it to power light bulbs, blenders, cell phones, laptops, and other small appliances. This project will help one develop engineering skills while learning about a clean way of generating electricity.

The project was created as part of Infrastructure Academy's environmental technology curriculum for high school students, so it is intended to be both achievable and affordable.

Before continuing with the actual bicycle generator, one should understand how it works, and the components that make it up. View the PowerPoint presentation before moving on to the next step.
______________________________________________________________________________________

Parts Tools

- 2" X 4" Wood
- Wrench
- V-belt
- Saw
- Diode
- Wood screws or nails
- Battery
- Hammer or Screwdriver
- Inverter
- Tape Measure
- Wire
- Screwdriver
- Motor (12-V or higher)
- Perforated plumbers steel
(if motor does not have mounting bracket)

Note: The bicycle generator could be accomplished by skipping steps 5, 6, 7, and 8, to save money, but connecting anything other than a halogen lamp directly to the motor is not recommended due to the varying voltages.

Step 1: PowerPoint Presentation

Comments

[JCG5]

Does the diode control the direction of the electricity?

[dmetcalf2]

here is a great way to go green and get some much needed exercise

[gpdas]

Very good.

[ihaveguitarskills!]

How much do you think this would cost? Minus the bicycle.

[ExxoShock]

I was wondering. What affects of a larger than 12V motor on the amount of electricity produced? Because I would like it as efficient as possible, without it being overkill.

[ExxoShock]

Good job, could have been more detailed, but other than that, I applaud you.

[wagman45]

is it possible to run an inverter straight from the generator without a battery? or do i need one for any excess energy produced? could i just use a capacitor?

[ExxoShock]

Im not an expert, but you probably can, Yet, if you dont have a battery, you wont have any power if you stop, yet if you have a battery, it can charge the battery, so you can stop if you want.

[wagman45]

note: i'll be using a charge controller

[Aron313]

Where did you get the motor?????

[Daniel Deacon]

correct me if im wrong but it looks like a 24 volt 250 watt electric scooter motor

[wozzz]

Is it ok to charge a 12 v battery with a 24v motor?

[Daniel Deacon]

Sure In fact you need at least 15 volts to efficiently charge a 12 volt battery this is because of the internal resistance. I wouldn't risk going over 30 thou :D

[wozzz]

Has the base RPM of a 12v DC motor, to be taken in consideration?

[wozzz]

What should be the minimum specifications of the diode?

[Tabbytha]

What kind of motor? A stepper motor or another kind?

[bradpitcher]

In step 5 the author explains to use a 12 V DC motor

[viciousz0rz]

What is the overall price of a project like this (if I already have a bicycle, anyway)?

[windigoking]

would it make a difference if you used a mountain bike and added a fly wheel? That way you can start on low gear to get the fly wheel spining and slowly build speed so you can have a higher rpm, and keep it with a smaller effort?

[EMAMD]

the difference there is less effort, its good to add fly wheel. take note the generated rpm to the dynamo must be same or slightly high on the rpm rating of the dynamo.Why? because if less rpm, less voltage can be generated and not enough to charge the battery,if over rpm it may damage your dynamo because of over current to the coil of your dynamo.

[windigoking]

then instead of a motor, use a car alternator. they are designed not to over charge.

[IncrediblyCondensedBlackMatter]

that is exactly what i did with mine. it was a lot of extra modding, but basically i took two gear cassettes, and rigged them onto the flywheel in opposite directions, so you can get the flywheel going in low gear, then stop pedaling or switch to a high gear and the flywheel will still turn the generator. it took me a while to figure out the gearing, and i had to widen the rear forks to fit both sets of gears, but it rocks. i used two steel 45lb gym weights welded together for a flywheel...

[ltavera]

did you have pictures of your work?
I will like to make my child's tv work with a bike!! I need more instruccions!

[windigoking]

sounds great, how is it working for you? can you post pics?

[mr.incredible]

Wouldn't a bridge rectifier be more efficient?

[EMAMD]

Its good to use fullwave rectifier in order to use all the waves of AC the positive and negative cycles.

[mehendalek]

Thats right... single diode filters half the cycle only if AC Dynamo is used. In this case he is using DC Dynamo. The diode is only to avoid reversing of supply.

[cyfekt]

Could you possibly use a larger motor, and 6 batteries??

And if you did what kind of inverter would you need??

[XPProductions]

Does the motor size make difference, or only the voltage matter?
If I plug three lamps in series, they will light gradually?

Thanks.

[windigoking]

also would using a car alternator be of help, since it has the voltage regulators built in?

[mahesh.ganpate]

mind blowing how much current flowing the full rpm . variables rpm variable curent flowing its same to wind turbine generator.. generator specification

[miggysay]

Awesome post. I'm really interested in powering my room with a bike and I was wondering if there is any way to have a kind of visual to see how much power the battery still has, kind of like a cell phone battery bar? Also, does the voltage of the motor and the inverter matter? Is it better to have a higher voltage or anything?

[miggysay]

Also, does it matter which kind of diode I get?

[elsaericson]

what kind of battery would be best for charging a laptop?

[The Incredible IT Maker]

Your standard automotive battery. anything 12 volt pushing around 50 amps or higher

[TANZMEISTER]

a deep cycle battery would be advisable

[patnat]

if i wanted 2 miss out the battery and go to the inverter wld that be an problem ?????
i was goin to connect the diode to the inverter would this lead 2 any problems ??????????

[macnomad84]

The battery serves the purpose as a voltage regulator into the inverter.

The motor, connected through the diode will generate a fluctuating voltage anywhere between +5v/-5v, even more. The diode takes the positive (cuts off the negative) and uses that potential to drive the Lead Sulfate/Lead Oxide battery electrolytically (charges the battery). The input voltage must be greater or equal to the cell potential (i think 2V? ) for it the battery to charge.

The inverter turns a constant DC source into 60Hz AC.

[juanangel]

Excellent idea with many possibilities
Have you thought of having the motor mounted directly do the bike and tire[sort of like those light generators for bikes] (that way you can have a moving charging –riding-excersising bike). Of course you need to have a battery platform. This way you still have an usable bike and no need for a drive belt or taking too much room. The stand stays the same for stationary use. Other advantages, power for a radio, illumination,etc. while riding it outside. Waterproof the inverter and hang it in the bike for anyware use.The generator shaft can go directly on the tire, adding more power since it will be a smaller diameter.

[elsaericson]

smoothie and breakfast ideas are sooo illll