The sustainable energy project turned into Tesla Motors, and that seems to be going well after years of struggles and naysayers. "If I had a dollar for every time someone brought up DeLorean or Tucker I wouldn't need to IPO," Musk said in conversation with Walt Mossberg and Kara Swisher at the D: All Things Digital conference here.
Tesla's stock price has soared after the company had a quarterly profit, and its market cap is more than $10 billion. Tesla also repaid the entire balance of its $465 million loan from the Department of Energy, nine years before than the contract required.
He announced during the interview that Telsa Supercharger network, which speeds up the battery charging for longer distance travel, is expanding the number of locations.
"We had to make something quick to charge," Musk said, "and we are going to have dramatic acceleration of the Supercharger network, and will triple the coverage area. By the end of this year will cover most of the major areas of the U.S. and southern Canada, so you could drive from Los Angeles to New York with the Supercharger stations."
Musk also hinted at another Tesla announcement coming on June 20.
Musk said that Telsa would have a third-generation $30,000 car in three to five years, and that it would likely be 20 percent smaller than the Model S and at higher scale production than the current $60,000 Model S, which is expected to sell 21,000 units this year.
By the end of this year, Tesla is expecting 25 percent gross margins absent of credits, Musk said. The margin includes consumer tax credits, but not subsidies.
Musk also talked about his other passion -- colonization on Mars. He noted that it is a dangerous and challenging undertaking but worthwhile.
"Either we spread earth to other planets, or we risk going extinct," Musk said. "An extinction event is inevitable, and we're increasingly doing ourselves in. We want to have a future where humanity is exploring the stars, and where what you see in the movies comes true."
In his Spockian way, Musk doesn't view travel to Mars as illogical. "We're not violating any laws of physics. It's difficult but achievable," he said. "If you look at various planets, Mercury's too close to the sun, Venus is still pretty hot, and then Mars is on the other side and colder than Earth, but it actually gets above room temperature on Earth on a hot day in the summer. So we could export our greenhouse gases," Musk said as the audience laughed. Mossberg suggested bringing all the GM cars to Mars to warm up the planet.
"Mars is a fixer-upper of a planet, but we could make it work," he concluded.
Musk was asked about his "hyperloop" concept, which he described as a cross between a Concorde supersonic jet, a rail gun and an air hockey table, for speeding up travel between Los Angeles and San Francisco more cheaply and faster than a bullet train. "Even if I am wrong about the economic assumptions, it would be a fun ride," Musk said.