We may not be too far away from a world where solar panels can be rolled atop your car or sprayed onto the windows of your house thanks to something called perovskites, a range of materials that can be used to harvest light. Solar researchers love perovskites because they are not only efficient but also cheap. And when mixed with liquid solutions, they could be deposited on a range of surfaces, which could play a crucial role in the expansion of solar energy. On top of that, they also require much less energy to make than traditional silicon-based solar panels.