pv's
photovoltaic solar cells are black. really black. blacker than anything i've ever seen. so i was thinking. the earth usually immediately reflects some 30% of the sun's radiation back into space. ie its albedo. not to be confused with its libido. anywho, if we cover the earth with black cells that reflection wouldn't happen. the extra radiation would be absorbed and used and released as heat. in other words... [wait for it]... solar cells cause global warming.