Though the Unites States comes only the fourth place as a solar energy market, behind Germany, Italy and Japan, its solar energy technology is farther advanced than any other country in the world, Rhone Resch, president and CEO of the U.S. Solar Energy Industries Association, said.

Germany is a larger market than the United States and Japan has bent to the photovoltaic industry for decades. But it is the United States which holds the cutting edge, he said.

"When you look at the innovation that's coming out of our universities and our research laboratories as well as so many of the companies, I would actually argue that with respect to the actual technology, the efficiencies, the applications that solar is used and automatically the scale on which solar is applied, the U.S. is significantly farther advanced than either Germany or Japan with respect to technology development," Resch told Xinhua.

Photovoltaics was invented in the United States' Bell Labs; the lowest cost panels are manufactured by a U.S. company, First Solar; the highest efficient panels in the world are manufactured by a U.S. company, Sun Power, Resch noted.

According to the expert, the future development of solar energy industry depends on breakthroughs or innovations in regard to the cost, efficiency and the appearances of solar panels.

Regarding cost, he explained that since a solar panel is a commodity product, every company out there is trying to drive their cost down. "If you can lower your cost and assure that you have high quality, then automatically you are going to win the race."

According to Resch, the wholesale price of photovoltaic panels has come down by nearly 50 percent in the last two years. Currently in the United States as an incentive to promote this industry, all homeowners and businesses get a 30 percent tax credit from the federal government and state governments.

There has been a big push around the world to improve the efficiency of solar energy, Resch said, citing some Chinese companies which he said have made great strides.

"There are tremendous new companies, new products that will be available in the next 12 to 18 months that will both lower the cost as well as increase the efficiency of solar," he said.

In regard to the appearance of solar panels, Resch says the future trend is to merge the panels with the buildings they are installed into so they are not so protruding as now. "Specialists will come in and look how to integrate solar into the skin of the building, into the roof materials of a building, into the shingles of a building," he said.

Dow Chemical is making a product that looks just like a roof shingle that were previously used in the United States with solar integrated into it. That kind of building-integrated solar panel is something that consumers want, Resch said.

"You are starting to see it more and more commercially available. And I think it's really going to change the image of solar energy and automatically the application of solar in the United States."

Resch says the biggest competition in the industry will occur between crystalline silicon and thin film.

"Crystalline silicon still represents the vast majority of the solar manufacturing today. But thin film products are coming on in a significant way," Resch said.