Glass Hot Air Balloon?

Question

I know glass can capture a lot of heat. They say cars in the sun can hit 150 degrees. And I've seen systems where they get glass boxes up to 700 degrees (with nothing but sunlight).

So whats the problem with a glass hot air balloon (other than structural)? It wouldn't need fuel if you painted the bottom with black paint to catch heat.

Answer 1

Glass is quite dense and therefore is a glass balloon is a lot heavier than a canvas balloon and so requires a lot of upward force to lift it.Hot air is probably not strong enough to lift a glass hot air balloon

Answer 2

You have a good idea, but don't stop brainstorming. Yes, glass is heavy and fragile, but instead of glass, how about a black balloon inside a transparent one? The black to absorb the sunlight and convert it to heat, and the transparent one to act like a greenhouse to keep the infrared from radiating away and to keep the heat from being conducted away by the wind. Now we've invented the solar powered hot air balloon! It may take a while to collect the amount of heat you'd get from a huge propane flame, but then you needn't carry a propane tank and burner. You may keep the royalties, but please include my name on the patent application. You're welcome.

Answer 3

It's a tall order. For one thing, a glass balloon can't expand, so you'll have a lot more air to heat. Plus, there would have to be an opening to allow the heated air to escape, which would slow down the heating considerably.

Answer 4

Actually, the glass is too heavy and super thin Mylar works better. Unfortunately, you can't patent the black balloon in inside because it has already been done.