President Obama called clean energy "our generation's Sputnik" moment during his State of the Union address. One of the technologies he mentioned was solar shingles, a lesser-known photovoltaic energy source that looks like regular roofing shingles but could power homes more cheaply than common solar panels.

"Already, we are seeing the promise of renewable energy," said the president. "Robert and Gary Allen are brothers who run a small Michigan roofing company" called Allen Brothers, Inc. "After September 11th, they volunteered their best roofers to help repair the Pentagon. But half of their factory went unused, and the recession hit them hard.

"Today, with the help of a government loan, that empty space is being used to manufacture solar shingles that are being sold all across the country." According to a report by International Business Times, the brothers received $500,000 through the Recovery Act to retool their plant.

The president called for efforts to "spur on more success stories like the Allen Brothers."

The Allen brothers formed a new company for their solar shingles called LUMA Resources. According to the LUMA website, "The LUMA Resources Solar Rooftop System is simply put; the cleanest, easiest, and complete solar product available today." The solar shingles look almost exactly like traditional asphalt roofing shingles while costing less than regular solar panels. LUMA offers systems that can produce between 2,400 and 8,640 watts of electricity.

Another company involved in solar shingles is Dow Chemical, which a year ago received a $17.8 million tax credit to market-test their product, according to Technology Review. Dow says its PowerHouse solar shingles will be available in some U.S. markets in mid-2011.

This Old House magazine took a look at solar shingles back in 2008, writing "These systems — called 'building-integrated photovoltaics,' or BIPVs — combine solar cells with slate, metal, fiber-cement, even asphalt roofing. Electricity is generated when the sun strikes a semiconductor layer, typically crystalline silicon, laminated to the shingle's surface. One shingle by itself doesn't produce a whole lot of power ... but harness hundreds of square feet of them together, and you can generate enough electricity to power a whole house."

Solar shingles aren't cheap, and they are definitely more costly than asphalt tiles, but they are one of the technologies that could help fuel a cleaner tomorrow.