Despite great leaps in solar panel technology, the biggest obstacle hindering their widespread use is quite pedestrian: stubbornly high installation costs. While the cost of panels has dropped by half since 2007, total installation costs, which include panels, labor and additional equipment, declined just 20% over the same period.

Charlie Korman, manager of Solar Energy programs at GE's Global Research Center, in Niskayuna, New York, says that for the market to take off "we need to get to the point where people can buy the system without relying on subsidies."

Korman is working hard to get there. He and his team of GE engineers have developed a system that aims to bring installation costs from the current $6.50 per watt to just $3. At that price, the savings provided by the panels would more than offset the expense of mounting them on the roof.

Korman's solution is elegantly simple. "Right now, solar panel arrays are essentially high-voltage systems," he says. In such a system, the panels are linked in a row like rail cars and feed 600 volts or more into a single high-voltage cable.

To handle all this voltage, home owners must hire specially trained installation workers, buy equipment switching the direct electrical current generated by the panels to the 120-volt alternating current used by most home appliances, and install special wiring.

But GE's engineers have found a solution to get around this problem and do it cheaply. They've built solar panels that can be linked in such a way that the output is socket-ready alternating current.

They've also designed a standard installation kit so that the array can be assembled by an ordinary roofing contractor in half a day, as opposed to the two days it takes at the present. Korman says that the system has 60% fewer components than the current high-voltage kits. His goal is to slash installation costs by half and cut energy waste. "It's is going to be good for 25 years," he says.

GE has built a working prototype of the system and Korman's engineers are exploring next commercial steps with other GE businesses.

GE is one of the largest investors in renewable energy. Last week the company announced plans to build a new plant near Denver, Colorado, producing high-efficiency thin film solar panels. The $300 million investment will create 355 high-tech manufacturing jobs. The company will also hire 100 new researchers at the Niskayuna research center.

The U.S. solar energy market stood at $4 billion in 2010. U.S. installed solar capacity is expected to nearly triple to 4.5 gigawatt in 2015.