...AND CHEAPER...:

Researchers from the Lawrence Berkeley National Lab in California say another advantage exists -- an environmental one. If a fleet of autonomous electric taxis were to replace everyone's gas-powered, personal cars, we could see more than a 90 percent decrease in greenhouse gas emissions and almost 100 percent decrease in oil consumption from cars, all while saving money in the long run. Right now that may seem like a long shot, but a study earlier this year said that 44 percent of Americans would consider buying a driverless car in the next 10 years, even if it would cost $5,000 more.

Now this may seem obvious: if you started to only build electric cars, emissions and oil consumption will fall. But what surprised Berkeley researchers was how most efficient such a system would actually be, even with the relatively high cost of electric vehicles today.

"You don't often find that, where the cheapest is also the greenest," said Jeff Greenblatt, co-author of the study.

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