LAS VEGAS —

With more than 20,000 panels, the largest rooftop solar array in the U.S. (second largest in the world behind a 7.52-MW installation in Punjab, India) is about to be commissioned on top of the Mandalay Bay Convention center in Las Vegas, Nevada. A 6.4-MW solar array, which uses SMA inverters and panels from Hanwha Q CELLS and JA Solar, covers the 20 acres of roofs on the convention center and its neighboring buildings.

NRG developed the project and sells the power back to Mandalay for a cost that is “about the same” as the cost that the resort was already paying for electricity, according to Cindy Ortega, MGM Resorts chief sustainability officer. Ortega was among several guests, including U.S. Secretary of Energy Ernest Moniz, who visited the array on Wednesday, the day before the ribbon cutting for the new project.  Ortega said that the solar panels will generate enough energy to meet about 20 percent of the electricity needs of the resort and indicated that there are plans to expand it in the future. In addition to meeting the energy needs of the resort, it will also serve as a shining example to guest who visit Mandalay Bay and can look out their windows and see the solar on the convention center roof.

U.S. Secretary of Energy Ernest Moniz was in town to give a speech at the Wednesday General Session at Solar Power International. He stopped by the rooftop array on his way out of town and spoke to journalists from the roof.  “The more we get solar out there, the more the costs get driven lower and lower,” he said. He touted the first five large utility solar projects that the U.S. Department of Energy helped kickstart as examples of the success of its loan program.  “We don’t have to help anymore,” he explained, “there are 17 projects now with complete private financing,” he said. 

CSP plants are not as far along as PV projects, said Moniz, adding that the DOE has helped fund some larger projects that are just coming online, such as Ivanpah, or are still under development, such as The 110-MW Crescent Dunes CSP project near Tonepah.  “We are supporting the first ones getting out there and we hope that after that experience, costs [will] come down and the private sector will advance those both in the United States and in places like North Africa, which has very good conditions for solar thermal,” he said.