In this age of green energy, the high cost of solar power has continued to be a big concern for energy providers. Researchers in Golden, however, think they have the solution.A technological breakthrough may make what's called concentrated solar more affordable. The concept behind concentrated solar was to use large panels of curved glass to focus the sun's energy on a tube filled with oil. The heated oil is then used to make steam which powers a turbine and eventually creates electricity.Senior scientist Gary Jorgensen from the National Renewable Energy Laboratory said using glass just isn't practical."They have problems with their weight and their cost. That's been the problem with renewables all along over the years is the cost hasn't been able to compete with the fossil fuels," said Jorgensen.He said a new metal reflector he helped create with a silver polymer will make the technology much lighter and cheaper."That translates into, in terms of installed field cost, of a reduction of about 25 percent, which is an amazing reduction," he said.NREL said the cheaper cost will make the solar technology more attractive to energy producers. Last week, Xcel Energy broke ground on a new project near Grand Junction that will integrate concentrated solar with an existing coal power plant."This is the first test of this kind in the country," said Xcel Energy spokesman Joe Fuentes.Xcel will test the technology for a year and hopes to expand it to other plants around the country."Our experts have looked at this. It looks pretty good, it looks pretty promising. I mean we're investing $4.5 million into the project so we think it will work," Fuentes said.Xcel said the solar project near Grand Junction will be completed by the end of 2009. The project will use glass reflectors because the new metal ones are still being commercially produced. Xcel said it will try to incorporate the new metal reflector technology as it becomes available.NREL said each concentrated solar trough is capable of producing enough electricity for 50 homes.