Many people when reading about solar balloons come to a conclusion that solar balloons are basically the same as hot air balloons. I also started thinking they are the same thing when first hearing about solar balloons all those years ago. Truth is solar balloon are basically the same as hot air balloons, but there are some differences between the two.
Connection between solar and hot air balloons
The connection between solar balloons and hot air balloons is pretty obvious. They both use hot air in order to provide lift. The only difference would be that hot air balloons do it on a much larger scale.
Solar balloons can be made to look like hot air balloons, as you can see from the image above. Hot air balloons however are a whole other level. They provide their own hot air, using a burner at the mouth of the balloon down below. Sun does help some, but you get more hot air using the burner. Hot air balloons are also much bigger, duh. They can carry a gondola at the bottom with passengers in it. In summary, yes, solar balloons are just like hot air balloons, but with a couple of differences in scale at which they do things.