The Heliotrope solar-powered home created by German architect Rolf Disch rotates to follow the sun's rays.  The design generates enough energy to fully power the home and feeds surplus energy to the grid, making it the world's first energy positive solar home capable of producing five times the energy it uses.

The cylindrical-shaped Heliotrope has a series of balconies covered with vacuum-solar thermal collectors and features one large 6.6 kW roof solar panel called the Sun Sail that pivots (in addition to the house's rotation) to match the angle of the sun.  The pivoting motion allows the Sun Sail to produce about 30 to 40 percent more energy than a static solar panel.

The roof houses a hand railing system that doubles as solar thermal tubing for water heating.  The house also features triple-paneled thermal-insulated glass on the side of the house facing the sun so that the light streaming into the home is maximized throughout the day.

The design also includes rain-water collectors and a waste water purification system.  Currently, three Heliotrope homes have been built.

via Good Clean Tech