Electric bikes catching on in the U.S.

(WPRI/FOX Providence) - They're a cross between a bicycle and a scooter. Long popular in Asia, electric bikes are now catching on in the U.S. Pete Mangione shows us the latest way to go green while saving some green.

Peter Robles isn't using the family's minivan much these days instead, he's going electric.

Peter Robles, electric bike user: "I commute everyday to and from work, 8.9 miles. and on the weekends I'm on it."

With just a touch of a button, Peter can switch from pedal power to electric - allowing the motor on the front axel to propel the bike up to 30 miles per hour.

Bike store owner Bert Cebuler sells several types of electric bikes, all powered by removable lithium batteries that weigh around 7 pounds.

Bert Cebuler, NYCE Wheels owner: "Just like a laptop, it comes with a charger, you plug it in. It takes a few cents to charge up, same as a light bulb basically, and it stays on for about 4 hours."

A fully charged battery can last you 20 to 30 miles. The bikes have become extremely popular in Europe and Asia. … with 120 million being used in China alone.

It's estimated about 2-hundred thousand were sold in the US last year but experts expect that number to grow. Even though the bikes are widely available at stores including Best Buy and Walmart - laws for riding them vary from state to state.

There are some disadvantages to an electric bike.

Bert Cebuler, NYCE Wheels owner: "They cost a little bit more than regular bikes because you are paying for the electric system, and they usually weigh about 20lbs. more."

Prices range from 400 to 5000 dollars, but Peter says the bike pays for itself. By taking his nearly 20 mile commute on two wheels, he saves about 16-hundred dollars a year in gas.

We've checked with local bike shops, who said they do in fact carry electric bikes, called "Power Assist Bicycles". These bikes have an electric motor that will help you pedal, but won't actually work on it's own.