Ten free electric vehicle charging stations are now open to the public at Denver International Airport's east and west parking garages.
The stations, which opened Monday and use standard outlets, will fit with most electric and plug-in hybrid vehicles, such as the Chevy Volt, Nissan Leaf and the plug-in version of the Toyota Prius.
DIA officials solicited competitive bids for the charging units, and Illinois-based Telefonix Inc. won with a hard-to-beat offer: free stations that cost less to operate.
Most commercial charging stations are classified as Level 2, which take more electricity to operate, but Telefonix provided DIA with Level 1 stations, which conserve more energy.
Level 1 needs only a 12-volt line, compared with the next tier, Level 2, and its 240-volt requirements. It has been referred to as a "trickle charge."
The trade-off, though, is the longer charge time. But airport officials say that it takes about eight hours on average to fully charge a car while the average DIA customer parks for nearly a day and a half, providing enough time to fill up.
There are five stations in both garages on level 1 between rows E and F. They are available on a first-come-first-served basis.