ANN ARBOR – The Downtown Development Authority, after installing 18 electric vehicle charging stations in downtown Ann Arbor 18 months ago, is now looking at adding more.

Dave Konkle, the DDA?s energy programs director, told Ann Arbor.Com that the stations are getting roughly 80 percent use each day. Because the 18 charging stations were funded by a federal grant, the DDA has to submit quarterly reports to the U.S. Department of Energy on their usage.

The earliest report at the end of June 2012, right after the first chargers were installed, showed 669 kWh of electricity used at 10 charging stations at the Maynard, Ann/Ashley, Forest, and Fourth/William parking garages.

Eight other stations were installed ? six at the Library Lane underground garage and two at the surface parking lot at Fourth and Catherine in Kerrytown ? and electricity usage quadrupled to 2,742 kWh for the third quarter of 2012.

With more and more drivers learning about the stations and plugging in, usage nearly tripled to 7,888 kWh for the fourth quarter of 2012. That went up again to 9,954 kWh for the quarter that ended in June.

At roughly 13 cents per kWh, the DDA paid more than $3,800 for the 29,241 kWh of electricity used at the charging stations through June. Konkle said the DDA isn’t charging additional parking fees for the electricity usage because officials want to encourage more EV owners to come downtown.

City Administrator Steve Powers noted the DDA has included in its five-year project plan the installation of about 15-16 more EV charging units throughout the public parking system, including lots and structures, with an estimated cost of $100,000.

Representatives of the city, DDA, U-M, Clean Energy Coalition and DTE Energy were expected to meet on Friday to discuss further electric car charger development in Ann Arbor. Konkle described it as the beginning of a process.

Konkle said the cost to install the first 18 charging stations last year was about $5,000 per charger. He said they could be installed for less, but about $1,200 of the cost per charger was for usage monitoring capabilities.

Mark Rabinsky, project manager at the CEC, said Ann Arbor is definitely in the top range in Michigan when it comes to installing charging stations. His organization expects to see more and more EVs hitting the road in the years ahead.

Within the Detroit metro area, Pike Research predicts by 2017 there will be 33,400 personal electric vehicles on the road.

The charging stations installed at the Fourth and Catherine surface lot in Kerrytown were purposefully located in the far northwest corner to maximize sun exposure. That’s because the

Konkle said three more EV charging stations are going in the new First and Washington parking garage, which is expected to open this fall. A new 720-space parking garage U-M is building on Wall Street also is expected to include charging stations.