In the hunt for ever more reliable and efficient green energy production, the Australian National University (ANU) has developed a solar dish with an incredibly high sunlight-to-steam conversion rate. That's right, steam. Instead of photovolatic solar panels, which convert the sun's rays directly into electricity, the so-called "Big Dish" reflects them back at a receiver, suspended in mid-air, which converts water into steam. The gas can then be used to power a motor, or stored for long periods as molten salts. The latest breakthrough? A new receiver that's 97 percent efficient.