Did you know the warmth you feel on your skin from the Sun is actually a type of energy? It’s called solar power—and it’s a pretty big deal. “Solar” means it comes from the Sun, like those solar panels you might spot on rooftops. They soak up sunlight and turn it into electricity. Pretty impressive, right? The Sun does so much more than just warm us up—it’s essential for life on Earth, helps grow our food, gives us beautiful sunsets, and even powers some cool science experiments.

Today, we’re going to dive into a super fun Sun Science Experiment: building a Solar Updraft Tower! This hands-on activity is straight from my Sun Science Family Unit Study—a jam-packed resource full of sunny facts, creative learning, and 10 exciting topics with activities your kids will love. Each of my Family Unit Studies will have one larger project, and this is the one from Sun Science!

Now, let’s harness the Sun and get experimenting!

Sun Science Experiment – Build a Solar Updraft Tower 

First, what is a solar updraft tower? These tall, slender chimney-like towers generate electricity by using the energy from the Sun to heat the air. The heated air rises to the top of the tower, creating a wind force that causes the wind turbine (or in your project, the pinwheel) to move. And there you have a renewable-energy power plant. Now, let’s create one together! 

For this sun science experiment, you will need the following materials.  

• three tin cans (top and bottom cut off)
• electrical tape
• large metal paper clip or other thin wire
• markers
• thumbtack
• two books of equal size
• 15x15cm piece of white printer paper
• scissors

And lastly, a sunny day!

Once you have gathered all your materials, or in my case, finished my third bowl of tomato soup, you’ll need those cans!  Watch this educational video called “The Power of Sunlight!” https://www.youtube.com/watch?v=0Qmgdz9E47s. This fabulous video by SciShow Kids explains how Solar Updraft Towers work and the steps to build your own.

You can also download my free instructions and follow along below as we make ours!

Step 1: Build the Tower
First, we stacked the three cans on top of each other. To keep them steady, we wrapped some electrical tape around the stack. Next, we took a piece of metal wire and taped both ends on each side of the top can. Then, we taped a thumbtack right in the middle of the wire, making sure the point was facing straight up.

Step 2: Make the Pinwheel
Once the tower was ready, we started working on our pinwheel. My son wanted to decorate his with a few sun pictures—feel free to get creative with yours too!

To make the pinwheel:

• Start with a square piece of paper, about 15 cm x 15 cm.
• Cut diagonally from each corner toward the center, but stop before you reach the middle. Try to leave the same amount of space from the center on each cut.
• Fold in every other corner and bring them toward the center.
• Tape the folded corners in place in the middle.

Finally, press the center of your pinwheel onto the thumbtack at the top of the tower. And there you go—your solar updraft tower is ready!

Step 3: Find the Sun 
Now that you have built your Solar Updraft Tower, you can find a sunny spot. Then, place it on top of two books, leaving a gap for the air to flow through the bottom can. Leave your tower in direct sunlight and observe what happens! Finally, record your observations.

Step 4: Extension Ideas

For our tower, it took about six minutes in the Sun before the pinwheel began to turn. It kept spinning at a consistent speed until the paper tipped sideways.

This sparked some great extension ideas for this sun science experiment—what would happen if we stacked the books higher? Or if we painted the cans black? We also wanted to try making the pinwheel out of cardstock to see if that would help prevent it from tipping off the thumbtack. Lastly, the boys wanted to bring it outside and see if that made a difference, which they really enjoyed because we had some help from the wind! 

This was such a fun and educational sun science experiment to enjoy as a family. We learned a lot about the benefits of solar power and how it helps the Earth, and it really sparked our interest in exploring other ways we can use the Sun’s energy.

If you’re ready to learn more and dive into a hands-on Family Unit Study about the Sun check out my Sun Science Family Unit Study. It lays out everything for you, step-by-step, with 10 fascinating topics to explore. And the best part? It’s designed to work for children ages 4 to 12, so the whole family can learn together!

Sun Science Unit Study

Check out a sample and grab your copy right here: 
https://shop.tstest18.techsurgeons.com/products/family-unit-study-sun-science

Thank you so much for reading, my friend!

xo
Sarah