There are many reasons to build your own bike generator. Electricity in emergencies, recovering wasted energy from exercise, and of course the cool factor. Building a bicycle generator is actually a very simple task that even the not so handy person can do on their own. All it takes is understanding how to combine the parts and a bit of time to assemble everything. The plans found below are for building a stationary or exercise bike generator.
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Warning: Working with electricity can be dangerous. Take proper precautions and consult a professional, we provide this for information purposes and are not responsible for any actions you take based on said information.
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Bike Generator Setups
Bike Generator Construction
Cost Information
Which bicycle generator setup is right for me?
First let’s cover a couple different uses that will determine what parts will be required to make your own bicycle generator. The most simple configuration involves the bicycle, a stand, and a generator. Nothing more. This is usually most useful for simple science fair type exhibitions of the principles involved because the electrical output will vary depending on how fast the bike is being pedaled and it will be hard to get enough torque without a belt or chain. It will also stop producing electricity as soon as the pedaling stops. Since the best generator to use with a bicycle is a DC generator you won’t be able to use the most conventional (AC) electronics with this setup. A more advanced and useful configuration involves the bicycle, stand, belt, generator, batteries, and a power inverter.
The addition of the battery or batteries allows the storage of energy from pedaling which can then be used as a later time. It also enables the use of higher energy demand electronics since you can store a small amount of power over time and then draw greater amounts in a short period when needed. The output from the battery will also be constant removing any concerns about energy fluctuations in the system like with the previous setup. Using the inverter enables you to convert the electrical output from DC to AC which most consumer and household electronics use. It also means having a convenient socket to plug things into rather than having to wire them directly which is a big hassle.
How do I construct the bike generator?
As mentioned above there are multiple setups possible (in fact, even more than mentioned here) so the first step in construction is deciding which you’re going for. Both configurations have an identical starting setup which consists of a bicycle held in a training stand. The use of a bicycle training stand is great for two reasons. First it means your bike can easily be removed from the system and used normally while being easy to hook up again. Second it provides a very easy mounting place for the generator near the bicycle wheel. This is because training stands include a resistance wheel to provide variable pedaling difficultly. You simply remove this resistance setup and put the generator in its place using either a purchased or DIY bracket. There are many different bicycle training stands but I prefer the Bell Motivator Mag Indoor Bicycle Trainer because it’s highly rated and has an easy adjustable screw to changing the height to fit your bicycle/generator combination (see image below).
There are a variety of ways to attach the generator to the training stand. Some people prefer to just drill holes and attach the two parts using nuts, washers, bolts, and some epoxy to hold everything tightly in place. You could purchase a cheap stick welder, get some practice welding together some scrap metal, and then weld the two together. There are also pre-made brackets you can simply attach after removing the resistance wheel. You just need something sturdy enough to allow either the bicycle wheel and generator to touch (make sure you have a flywheel on the generator shaft for contact/torque) or support a belt between the two.
Once you’ve got this setup complete you’re well on your way to having a completed bike generator. All the remains for the first setup is to connect the generator to your desired output (DC not AC) such as a DC light bulb and start pedaling. If you’re going for the more useful second setup connect the generator to your battery. Some people like to include a charge controller in between the generator and battery as it prevents overcharging which could be dangerous but if you’re on a budget you can check the charge level using a multimeter. Now the battery can store energy and also connect to an inverter which will include a standard socket allowing you to use various electronics powered by the energy of cycling.
Warning: Setup #2 using batteries can be dangerous if the batteries are overcharged. Use a charge controller in between the generator and batteries to prevent over charging or monitor the charge level.
Additional considerations to make are using a single battery or multiple batteries. The advantage to multiple batteries being that you can store more energy at a time. Storing energy can also allow you to obtain higher wattages than you would get during pedaling. The wattage rating of the inverter determines the maximum load that the inverter will be able to handle. Look at the devices you plan to be powering and make sure their wattage requirements are lower than the inverters rating and be sure the inverter can safely draw power from the battery you’re using.
I hope you’ve found this useful and enjoy your new clean, green energy source while also burning some calories at the same time. If you have any questions or comments please leave them at the bottom of this page. We love to hear your feedback!
How much will a bicycle generator cost me?
The costs involved depend a lot on the components you choose to use. You have to make considerations when choosing every part that will dictate what you get out of the system. Below this section is more information on the different types of parts you might choose. For the sake of creating a concrete price though we’ll assume you want to go as inexpensive as possible.
The bicycle itself won’t be included in the overall price. This is because it varies so widely and most people already own a bike. If you don’t own a bicycle already consider adding $50-$100 for a used bicycle in the classifieds. Also, the price below is for setup #2. Just remove the battery and inverter to get a setup cost for the more basic configuration.
Stand: Bell Motivator Mag Indoor Bicycle Trainer
$79.99
Generator: 300 Watt Bicycle Generator 3/8″ Belt Drive Pedal Power Pulley Dynamo
$199.00
Wheel to Generator Belt:80″ Adjustable Length V-belt 3/8″ Wide Size 3L Powertwist Bicycle Generator Belt
$79.99
Charge Controller:Sunforce 60032 30 Amp Digital Charge Controller
$84.13
Battery: PowerStar AGM 12V 12AH RBC4 SEALED BATTERY
$27.95
Inverter: Cobra CPI 480 400-Watt 12-Volt DC to 120-Volt AC Power Inverter with 5-Volt USB Output
$26.55
Total cost for a good quality bicycle training stand, 12VDC 300W permanent magnet generator, 30 Amp 12V Charge Controller, 12VDC 12AH deep cycle battery, and 12VDC 400W power inverter bike generator setup: $496.62
