The fridge is one of your home’s biggest energy hogs. Better insulation can make refrigerators much more efficient. And a panel encasing a vacuum is one of the best insulators known. But vacuum-insulated panels are too pricy for widespread use.

Enter some University of Michigan students. They took something called rice husk ash: the leftover husks from processing rice is burned for energy, and the ash remains. It’s high in silica and carbon. So they tinkered with the ash and developed a new core material for vacuum insulated panels. It’s about 50 percent cheaper than what’s currently available. And the resulting panels are such good insulators that swapping them into refrigerators could lead to about a 50 percent energy savings. They’re space efficient too: a one-inch-thick ash panel equals today’s four-inch-thick polystyrene panels.

Then Michigan business students partnered with the scientists to create a company called Husk Insulation. They entered the invention in the M.I.T. Clean Energy Prize competition. And on May 13th, Husk Insulation won the competition’s first prize—a cool $200,000. Which will be invested in further research and development.

—Cynthia Graber