• President Barack Obama, accompanied by Commander of the 89th Airlift Wing Colonel John C. Millard, walks towards Air Force One at Andrews Air Force Base in Md., Monday, Aug. 24, 2015, en route to Las Vegas, Nev.  where the the President will speak at the National Clean Energy Summit. (AP Photo/Jose Luis Magana)

    Rooftop solar key topic at clean energy summit in Las Vegas

    LAS VEGAS (AP) — President Barack Obama brought presidential star power to tout the benefits of solar electricity in Western states during an annual green power conference Monday in Las Vegas hosted by U.S. Sen. Harry Reid.