Interconnected fleets of driverless cars that "talk" to each other should some day make traffic lights redundant, says a guest an international transport conference in Auckland.

Scott Belcher, president of the Intelligent Transportation Society of America, says various levels of automation are already being introduced to the world's roads to make driving safer, cheaper and less environmentally harmful.

Although the ultimate goal is driverless cars - early versions of which are being tested by companies such as Google and Tesla - Mr Belcher believes privacy and liability issues will be harder to resolve than technical challenges.

"The issues we have with autonomous vehicles are social more than technological challenges," he said yesterday, outside a conference of more than 300 intelligent transport experts from the Asia-Pacific region.


"Privacy, liability and security are the three significant issues - once we resolve those, we will be moving into an environment of cars that don't crash."

Mr Belcher, a lawyer from an environmental protection background, says that will allow cars to be lighter and therefore less greedy for energy.

"Right now we build cars to survive crashes - that's why they are as heavy as they are," he said.

"So if you don't crash ... they can be much lighter, and can drive much closer to each other.

"You might be able to reduce the size of lanes if they are not drifting, and then you might not even have to have traffic lights."

Meanwhile, the US was about to set a cracking legislative pace, planning to introduce a rule in 2016 requiring car companies to make vehicles which communicated with each other to prevent collisions.

New cars would from a date yet to be announced be required to give out signals which would be received by other vehicles, and the information passed to their drivers to allow them to stop or take evasive action in time.

That could either be from technology embedded in vehicles or from plug-in smartphones, at a relatively modest cost of no more than about $200.


Although such a requirement will eventually filter down to New Zealand's car fleet, Motor Trade Association spokesman Ian Stronach said a need to create a global technical standard meant that was unlikely before the 2020s.

Mr Belcher believed older and disabled people had much to gain from greater levels of driving autonomy, to allow for their longer reaction times and reduced agility.