What was the reason (if any)? Just out of curiosity.
its a thing that has to do with ballance between the different green generators. solars pro is convenient setup its con is how expensive it is, waters pro is its cheap and has manned mode its con is its less convenient to set up(but that is debatable if you just use tin cable and a existing body of water to submerge it instead of building a tower), for the pro's and cons of wind ask spwnx he is our resident wind-nut.
now for a crash course in cables. you don't experience % powerloss with every block. you experience as a set amount of loss after a set amount of blocks with copper you lose 1eu per packet on the fifth block so if there is always a batbox or transformer as the fifth block then you experience no loss. tin is made for green generators because you experience no loss until block 40 but tin can only handle up to 5eu packets so after 40 blocks you have to connect to a batbox or transformer and use copper