Photo: Theo Kingma

 Larry Hagman is back in a new Dallas TV series as J.R., the Ewing family’s greedy and scheming oil baron. 
  But in real life he couldn’t be more different. A longtime renewable-energy advocate who installed one of the country’s largest residential solar systems at his eco-estate in Ojai, he is an outspoken spokesman for solar energy. He’s served on the board of SELF, a nonprofit that brings sun-powered projects to developing countries and is also the face of a new ad campaign for Solar World,  the German company that is the largest manufacturers of solar panels in America.
   The company has supplied him with a 1984 Airstream trailer in which he travels the U.S promoting solar power.
  “There are solar panels on the top so the whole thing is solar and green and gorgeous,” he told me during a break from filming on the Dallas set. “It’s fun to go around in. I want to go to the Ozarks. I’ve never been there before.”
 He paused, a twinkle in his blue eyes. “Where the hell are they?”