Elon Musk showcased his ambitions to make Tesla Motors Inc. a clean-energy behemoth on Friday, unveiling a new solar roof product at Universal Studios in Los Angeles.

As the sun set, Musk told hundreds of guests gathered in an outside courtyard on the "Desperate Housewives" set that Tesla and SolarCity Corp., the company that he chairs and which he aims to acquire, will make solar roofs that look better than normal roofs. He then showcased several houses with solar tiles gracefully embedded. Because the tiles are fully integrated into the roofs, many guests in attendance could not tell that they were solar.

"How do we have a solar roof that is better than a normal roof, looks better, last longer?" said Musk. "You want to pull your neighbors over and say, 'Check out this sweet roof.' "