Sunburn caused by water?

Unfortunately, your answer is wrong.

Indeed you are right, that there cannot be added any new energy in any case but the available energy is bundled.
The fact that there is no new energy is also evident from the point that there are clearly recognisable shaded areas on the leaf next to the bright focal areas. The light, which would normally have shone there, has been deflected. In the extreme case of the focal point, all of the light, which hits the water, is bundled in one single point.
Think about what will happen, if the energy, which is normally spread onto a great area, is suddenly collected in a small point.

You have not found the right answer yet, but looking at another hint can show you the right way. Do not feel discouraged, use another hint and think about it again.