The much-talked about driverless Google cars will be available to customers in three-five years, the head of Google's autonomous driving project said. However, the regulators and insurance industry are not sure if this will happen that quickly.

"I can't tell you you'll be able to have a Google car in your garage next year. We expect to release the technology in the next five years. In what form it gets released is still to be determined." Anthony Levandowski, product manager for Google's self-driving car technology, told a Society of Automotive Engineers (SAE) meeting in Washington last week. Levandowski said that the improvements are such that the software giant can make cars that can drive safer than human beings, The Washington Post reported.

However, getting the Google car on the road is a challenge for regulators and insurance industry as states have to figure out a way to license the machines rather than people, and insurance companies have to reassess how to assign fault after accidents.

Dan Smith, senior associate director for vehicle safety at the National Highway Transportation Safety Administration (NHTSA), did bring out the challenges of materializing the Google project. He said it would be a key challenge to figure out a performance standard that is "objective and testable for different scenarios where failure in autonomous driving systems could occur." Speaking at the SAE panel, Smith said a major part of the underlying challenge is to determine if the government should be looking at underlying electronics.

The safety benefits that come with driverless cars can be a major gain for auto-safety regulators as this technology can take human error out of driving. Nearly 33,000 people die annually in road accidents in the U.S.

Though Google gives an ambitious three-five year timeframe for self-driving cars to reach the customers, analysts give a longer timeframe to get the project approved by federal government. It is said that 2020 would be a reasonable year to hope for a completely self-driving vehicle.