The University of Michigan is set to get two additional hybrid cars later this month through the auto-sharing program Zipcar.

The cars will be Honda Insight Hybrids and will be set up in reserved spots at the Glen Avenue Parking Structure near Catherine Street.

The cars are expected to be operational by Aug. 19, bringing the size of the downtown and campus fleets to 18 vehicles, said Grant Winston, associate director of U-M parking and transportation services.

Zipcar is an auto-share company with programs across the country allowing participants to pay a fee to use the cars on an hourly or daily basis. Most of the Ann Arbor cars are now available for about $8 an hour or about $60 a day.

The program provides cars, with gas and insurance included, in central locations with free parking.

University of Michigan got its first Zipcars in 2006. It had more than 1,324 registered members at the end of July and was reaching a usage rate that was too high near the end of spring semester, Winston said. The optimal use of the cars is about 45 percent to ensure users can find the car they want most of the time, he said.

When Zipcar representatives were in town in March, Winston said some residents made it clear to the company there was a strong interest in getting Zipcar vehicles made by automakers based in Michigan. U-M also requested a better balance for the fleet, Winston said.

Of U-M's 13 Zipcars, three are Ford Escapes, said John Williams, a spokesman for Zipcar.

The company chooses its cars on a variety of factors, he said, including what users of the system are requesting. It also includes cars that produce fewer carbon emissions and hold their value.

Its fleet changes with what is new in the auto industry and the company would continue to consider future models of vehicles from Michigan-based automakers with the planned production of hybrid models in the future, Williams said.