One of the renewable energies that we always have on hand is solar energy, and we all know that we don’t use it enough. One of the reasons why we aren’t using solar energy more is that it’s usually impractical. Hopefully things will change in the future and we will fully exploit this unlimited source of power. This is one of the reasons why I thought that this concept was so great. You’d just be walking around and charging your gadgets at the same time!