Eking out more power from solar cells is an ongoing challenge for scientists, and now architect André Broessel has developed a spherical glass energy generator that's said to improve efficiency by 35 percent. Acting as a lens, the rig's large water-filled orb concentrates diffused daylight or moonlight onto a solar cell with the help of optical tracking to harvest electricity. In certain configurations, the apparatus can be used for solar thermal energy generation and even water heating. In addition to the oversized globe, Broessel has cooked up a mobile version of the contraption for domestic use and an array of much smaller ball lenses with dual-axis tracking that offers 40 percent efficiency. These devices aren't the first venture into concentrated photovoltaics, but they are likely among the most visually impressive. If the Barcelona-based architect's vision of the future comes true, you'll be seeing these marbles incorporated into buildings and serving as standalone units. Hit the source links below for the picture spread of prototypes and renders.