This is not true at all. To harness energy from the sun, the pigment chlorophyll is necessary. Animals cannot harness energy from the sun. They do not have chlorophyll or chloroplasts, as anyone who has ever taken a high school biology course will know. Solar panels are an invention, a man made machine. They are not found in living organisms. Cats lie in the sun because they are lazy, sleep a lot, and because the sun is nicer to lie in than shade.