Charleston rolled out a new way to pay for parking today that's aimed at making parking meters more convenient.

Starting Friday morning the city will sell SmartCards, which are essentially debit cards that work in parking meters equipped to accept them. Columbia already has such a system, as do some large cities like Philadelphia.

The plastic cards with microchips will cost $5, plus the cost of parking meter time. The first 100 people to acquire them Friday at the city's Department of Revenue, 180 Lockwood Blvd., will get the cards at no charge.

For motorists, the benefits of the SmartCard include not needing coins for parking meters, and being able to pay for only the amount of time used. Unused meter time can be refunded onto the cards.

Say a person parks at a meter, uses a SmartCard to buy an hour of time, and then finds out the store he planned to visit is closed. He could put the SmartCard back in the meter and get a refund for the remaining time.

Charleston's parking meters charge 25 cents for 20 minutes. The cards can not be used in parking garages.

City Department of Transportation Director Hernan Pena said about half the city's meters have been upgraded to accept the cards, and the rest will be upgraded by the end of the next year. The initiative will cost an estimated $130,000.

"We were at a time where we were going to replace old meters," Pena said. "For a little added funds, we were able to buy the latest technology."