How To Make A Solar Powered Fan STEP BY STEP [2021 Guide]

Posted 1 year ago by Kami

Keeping your home, office, or even your car cool is important, especially when the weather is too hot.

Fortunately, there is a clean and easy way to stay cool without the need for any electrical plugs or complicated wiring, which is solar powered fans.

In this article, we will provide you with a step by step guide on how to make a solar powered fan with very few components that you can find laying around your home.

Don’t worry, this is a beginner friendly guide with absolutely no geeky technical staff, so even if you have no experience, this article is for you.


1. 12-volt motor

To design a solar powered fan, the first thing we need to know is how big we need our project to be.

This will help us to accurately size our solar panel and battery system to ensure that our fan is efficient and it’s getting enough power.

12 volt motor for solar powered fan

For this reason, we always need to start with the main component, which is the motor.

The motor is the heart of the fan, it will consume the energy from the solar panel and use it to spin the blades, increasing the airflow and cooling your car.

For this project, we will use a small 12-volt, 1000 rotates per minute (RPM) motor.

You don’t have to buy a new motor, you can simply look around for any broken toy and get the motor from it. 

blades for the solar fan

You can also use an old computer fan, as it has a motor built in.

For the blades, we will use a 6 inch fan blade with 0.125 inch D-Bore.

After choosing the motor and fan blades, now it’s time to calculate how much power do we need.

Here is how to calculate it:

  1. The first step is to know the power rating of your motor and to do this you need to multiply the current (Amps) by the Voltage (V) to get the wattage (W). For the motor we have, it’s a 12 V motor with a 0.35 Amp, so the power rating would be 12 * 0.35 = 4.2 Watt hour. In other words, this motor needs 4.2 watts for every operating hour
  2. The second step to calculate how many hours will the fan work. Let’s assume it will work for 8 hours/day.
  3. The third step is to calculate how much power we use per day :

Power of the motor X number of hours = power needed each day 

So: 4.2 X 8 = 33.6 watts. This means, that we need to design a solar panel that generates at least 33.6 watts per day and a battery to store this energy.

2. 12-volt solar panel

Now after knowing how much energy the motor will consume each day, it’s time to pick the perfect solar panel for this project.

Here is how to calculate the best solar panel size for a fan:

  1. Calculate how many hours of sunlight your panel will get. Let’s assume the panel will only get 4 hours of sunlight each day
  2. Divide the power the motor needs every day by how many hours of sunlight does the solar panel get per day
12 volt solar panel to power the fan

The power needed per day / The number of hours the panel gets per day = The power of the solar panel

In our small project, the motor needs around 33.6 watts per day and we get around 6 hours of direct sunlight.

So: 33.6 / 6 = 5.6 Watts

And that’s it, we need a 12 volts, 5-7 watt solar panel to do the charging process efficiently. 

3. 12 Volt Rechargeable Battery

In order to store the electricity produced by the solar cell, so we can use it later at night, we need to build a storage system using rechargeable batteries.

Now, to calculate the battery size we need for a solar powered fan, we will use this simple formula:

12 volt batteries for solar fans

Battery capacity = power generated by the solar panel per day / battery voltage

So: 30/12 = 2.5 Ah = 2500mAh

Therefore, we will need a battery a 12 volt battery with 2000-2500mAh capacity

Note: Make sure that all your parts are 12 volts, as a 6 volt solar panel won’t be able to charge a 12 volt battery or run a 24 volt motor.

3. 1N914 DIODE

This diode has a very important job, which is letting the current flow in one direction.

In other words, it works like a gate, preventing the current from the battery to backfeed to the solar panel, damaging the solar panel.

Other Tools

In addition to the components, we still need a few tools to help us make the solar powered fan such as:

  • Suitable stand
  • A Soldering Iron
  • Solder
  • Wire
  • Wire Cutters
  • Hot Glue Gun
  • box/enclosure
  • Protective eyewear
  • Some pieces of wood
  • Gloves


  • wear protective glasses while soldering to save the eyes from any harms
  • Wear Gloves during soldering the wires
  • Try to avoid being near to papers or anything that can be easily fired during soldering 

How to make a solar powered fan STEP BY STEP 

STEP 1: Prepare your wires

Cut your wires to a suitable length, you can use a lineman’s pliers to do that.

If you want to install your solar panel on a roof or something, you can attach two or more, and solder them together till you get to the suitable length.

STEP 2: Prepare your stand

Make a suitable stand for the fan (a woody one for example), cut it by using a hand saw.

Try to cut it into three pieces, one for the base and the other two will be used for making a (T) shape, and then glue the three pieces together.

You can also make a fan stand using things like a small water bottle.

STEP 3: Connect the solar panel to the 1N914 Diode

The 1N914 Diode has two ends, one positive (the red one) and one negative (the black one).

The solar panel also has two sides: the red one which is positive and the black one which is negative.

Connect the positive side of the diode (red) to the positive end of the solar panel (red).

Then, connect the negative sides (black) together.

STEP 4: Connect the motor and the panel to the battery (positive side)

Grab all the red wires for the solar panel, motor, and battery, then solder them all together using a soldering iron.

STEP 5: Connect the motor and the panel to the battery (negative side)

Repeat the previous step but for the black wires this time.

Step 6: Use heat shrink

small heat shrink tubing for solar fan wire protection

Slide small heat shrink tubing over the wires you just soldered together and use a heat gun or a hairdryer to heat the tubings till they shrink.

This step is very important, as it protects the wires from environmental conditions and increases the current efficiency.

STEP 6: Fix the fan

Connect the blades to the motor, then use glue to fix the motor on the stand you made.

STEP 7: Enjoy the cool breeze

Voila! That’s it, pretty easy HA! 

In the end, we really hope you enjoyed this guide as much as we did.

If you made this solar fan yourself, please share photos with us in the comments section below.

Leave a Reply

Your email address will not be published.


A passionate solar energy engineer and environmentalist who loves to create content.