Time value of money. For example, a 5 yr zero coupon bond can be redeemed for a set value say $1,000 in 5 years so why does it have a value now, why isn't that value $1,000? Learn about economics and you'll see where the costs are.
Something like solar or wind, require huge start up costs. It's true the energy they generate are free after this, but they also need to be maintained. All these costs are factored into the price of the energy you get.
Also like a car, the longer they run the more they need maintaining, so maintainence is the main cost. However as the technology increases, they are becoming more efficient and cheaper, so should only get cheaper in the future.
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.