Scientists at Britain's National Physical Laboratory have developed a method of 3D printing Organic PV solar cells, which work best when the sun is hidden by clouds:

http://3dprint.com/1666/scientists-3...t-when-cloudy/

The technology is progressing fast, and should be in full use within the next 5 years. The cells can be printed in any color, or even transparent, and placed in any shape. They are also much lighter than traditional solar panels we are all used to so they can be placed on roofs and on windows without needed extra structural support. This is great for areas in the northern parts of America, Canada, and Northern Europe who see very little sun, especially in the winter.