This is not as easily answerable as it sounds. The most cost-effective system depends upon many factors. The most important in evaluating this cost is the amount of energy that you use as well as how much sunlight your home receives.
Once these two things are figured out, you can then apply them to the various solar energy systems, allowing you to have a more accurate determination of which would be most cost-effective for your needs. For more detailed information on determining these first, see renewableenergybug.com.
There is actually a company called citizens energy that will allow you to setup a plan with them where they will put a solar system up for you and lease it from you. I'm not quite sure how the system works but they put up the system and pay for it or atleast a large portion of it. Just something to look into maybe.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.