It seems to me that your friend will also replace the car he bought. His consumption habits are insane. It's very difficult for a person to overcome this. He could use the solar panel for another purpose. Frankly, someone with a consumption habit would either cancel the solar panel or simply let the system sit idle.

We are so easy to flip in opinion and we will make decisions rapidly, and rather thoughtlessly. There is very little "thinking slow" in our global culture now, very little deliberation and consideration - it is think little, act fast, come what may. Yet when what comes is a negative result, we also don't take responsibility for it, and instead look to lay blame on someone or something else.

Don't you think this is normal? There are so many different versions of the same thing these days that the human brain constantly craves something new. Like a little baby bored with its new toy. Always something new, always something different. Even if it's a different color, we want something new. Companies have figured out human psychology and are launching new products accordingly.