Tesla CEO sees self-driving cars taking over, in 20 years

Tesla Motors CEO Elon Musk sees the transition to self-driving cars as inevitable, though he notes that change should take decades.

Speaking at Nvidia's annual GPU Technology Conference in San Jose, Calif., Musk said it could take up to 20 years to replace the fleet of 2 billion cars on the road today at the current rate of 100 million new cars a year.

"It's not going to all transition immediately," he told Nvidia CEO Jen-Hsen Huang during an on-stage interview Tuesday. "It's going to take awhile."

Musk's comments come just before his company plans to announce a major software update Thursday to its high-end Model S electric cars, which is expected to improve the range of the vehicles before they need a recharge.

Autonomous cars have captured the fascination of the car industry, with many automotive companies such as Nissan and Audi and tech firms including Google and Nvidia working on the idea. The concept has the potential to save lives, but for now automakers are only taking small steps to add more automation into vehicles, such as parallel parking, computer-initiated emergency braking and warnings about shifting lanes. These companies are developing more sophisticated prototypes, but mass-market self-driving cars are not yet a reality.

Musk thinks that could change quickly. "We'll take autonomous cars for granted in a short period of time," he said.

For now, Musk said, a computer can control a car with relative ease at 5 miles per hour to 10 mph, since a vehicle can be stopped within the range of ultrasonic sensors. Above 50 mph on the highway is also fairly simple, since a freeway road isn't all that complicated. However, between 10 mph and 50 mph, things are much tougher, with cars needing to deal with urban environments, starting and stopping, pedestrians and other objects, he said.

"But we know exactly what to do and we'll get there in a few years," Musk said.

Earlier this month, Carlos Ghosn, the CEO of the Nissan-Renault Alliance, posited that the autonomous-driving revolution will come in three waves. He said the first wave of self-driving cars will emerge next year, then cars that can drive on a highway and change lanes will come by 2018. In 2020, cars that can handle city driving will become available.

A steering wheel and brakes may not be the only things at threat of becoming obsolete. Autonomous cars may become so much safer than people, Musk said, that it's possible human drivers could one day be outlawed, too.