How big a windmill would I need to put on my roof to power say, half my demand at home? And this is DC power, right? And I would need an inverter to make it AC power, and I could also cover my roof with solar panels, below the windmill mast! And maybe even put up 5-6 windmills on the beach, and one at the end of the dock, to kill off those pesky birds that are always crapping on my boat and dock! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />