This is a very nifty way to explain a concept with three simple pictures. The layout here is amazingly simple, but it had to have taken some planning to execute this so well.
The image on the top, being the illuminated bottle, is really the beginning of a story that allows the text to get across the idea that there are ways to solve problems; the image on the bottom left shows the hole (really? is it worth it? hmm) in the roof with the bottle sticking up just far enough to catch the outside illumination. The bottom right photo shows the "light bulb" in full illumination, giving the room enough light for use.
If this really does solve some issues, then the hole in the roof is probably worth it.
h/t to the Imgur blog.