DENVER, Colorado — Enterprise Rent-A-Car has announced it will put 100 hybrid cars into its fleet at Denver International Airport. The company has launched a push to put 5,000 more gas-electric hybrid vehicles into its national rental fleet, which already has 2,000 hybrids available.Customers will be able to reserve Toyota Camry and and Ford Escape hybrid vehicles online or by phone starting at $59.99 per day, about $10 more than a standard internal-combustion renter, the company said.Enterprise has a total of 26 rental branches that offer hybrid vehicles for rent. The car rental company has also designated eight branches that are E85/FlexFuel sites where up to 30 percent of the vehicles for rent can run on the gasoline-ethanol blend.For 'customers who really want to be green,' Enterprise and its affiliated companies National and Alamo are offering the opportunity to kick in $1.25 per rental as a 'carbon-dioxide greenhouse gas emissions' offset contribution. The money will go to clean-energy programs run by the San Francisco-based company TerraPass, and Enterprise's charitable foundation will match customers' contributions dollar for dollar up to $1 million total.Inside Line says: Making the company logo green was a good call. — Laura Sky Brown, Correspondent