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Solar Bag 25 or 50-foot Length

Fill our Solar Bag with air and let solar energy make it float!


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Product Name Price Qty
Additional Solar Bag String

Item #: WSLR-100

Solar Bags (2x25ft Long) and Solar Bag String

Item #: WSLR-225

Solar Bag (50ft Long) and String

Item #: WSLR-200


Usually ships the next day.

Availability: In stock

Solar Bag

Showing young scientists the incredible power of the sun can be a tricky task, but with the Solar Bag, you have a great (and gigantic) teaching tool. The Solar Bag, which stretches to either 50 or 25 feet when inflated, harnesses solar energy to expand and float into the air. It truly is a sight to behold as a giant, black "solar sausage" lifts off of the ground using nothing but sunshine! Don't settle for imitation bags that are only 10 feet and, let's be honest, just don't work. This is a 25 to 50 foot Solar Bag!

Using a Solar Bag is easy. Start by tying off one end of the bag, then filling it with air by running with the open end. Now just tie off the other end and watch as the heat from the sun causes the air inside to expand. Within minutes, the enormous Solar Bag rises into the sky and floats like a giant tube of solar science. Just be careful! The material that Solar Bags are made of has to be thin to enable the sun-powered flight. If you do wind up with tears, packing or masking tape will fix it right up to be used again!

What's Included?
2 - 25 foot Solar Bags
  • 2 - 25' (7.5 m) long Solar Bag
  • 400' (122 m) of Solar Bag String
  • Activity guide with student worksheets
50 foot Solar Bag
  • 50' (15 m) long Solar Bag
  • 400' (122 m) of Solar Bag String
  • Activity guide with student worksheets
What Does It Teach?

The energy harnessed in the Solar Bag comes straight from the sun, but we can't see it! Using the Solar Bag offers a multitude of scientific applications, beginning with how energy from the sun causes air to heat and expand, especially when amplified by the black surface of the Solar Bag. From there, teachers and students can engage in discussions of density, air pressure, buoyancy, convection, and more!

Customer Reviews

Tons O' Fun Review by Cory Jensen

I purchase these every year for a Solar Energy class. The kids love it (even the adults who are passing by are really impressed!). I nearly lost one one year, so now I tie a string to both ends of the bag. It doesn't really weigh it down, and I have a lot less heartburn about it breaking free. Here is a tip: When you are running to fill it up, don't stop running until you have it completely closed off. I noticed that most people will stop running as soon as it is full and then quickly try to close it off. The problem with this is that the inertia of the air continues forward as you are trying to close the bag and you lose some of the air. Keep running as you close it - it will work much better! (Posted on 6/8/15)

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You're reviewing: Solar Bag 25 or 50-foot Length

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  • How Does It Work?
    After rolling out the bag and tying one of the ends, you have to run around and fill the bag with air. Once it is full, tie the other end so that air can’t escape and watch the power of the sun at work! The solar energy will heat up the air inside the bag causing the molecules to move around and bump into all sides of the solar bag and make it rise!

  • How much weight will it lift off the ground?
    The solar bag is not intended to lift any weight while it rises.

  • How high can it float?
    The sky’s the limit on this one. We have let a solar bag or two go and its been observed by satellites at over 120,000 feet in the air!! This is the main reason that it is best to have some string attached so that you can inflate it, watch it float, and bring it back in order to use it time and time again.

  • Does it have to be a hot day?
    The best environment for the solar bag activity is to have the sun shining with a cool temperature. You want the air inside of the bag to be able to heat up from where it originally was so that it can rise.

  • How many times can you use it?
    The solar bag is made out of a light weight plastic material and will tear easily.  If you are gentle with it, you may be able to use it several times.