(left to right) Frank Miller, regional distribution manager for Toyota Motor Sales, and Scott Griffith, chairman and CEO of Zipcar, stand in front of one of the new Toyota Prius PHVs to enter the Zipcar fleet in Cambridge, Mass.

They don't go up for sale until 2012, but Zipcar has managed to snag eight Toyota Prius Plug-in Hybrid Vehicles (PHV) for its members to rent as part of a testing program with Toyota for the prototype vehicles.

Zipcar locations in Boston and Cambridge, Mass., San Francisco, and Portland, Ore., will receive the plug-in Prius cars, which have an electric range of up to 13 miles on a full battery and can be charged from a standard 110-volt outlet in up to 3 hours. For longer distances, the plug-in Prius achieves an average of 50 mpg, according to Toyota.

As with most hybrids in Zipcar's fleet, the Prius PHVs will rent for $7 an hour, including insurance, gas, and charging. Members in Massachusetts can find the plug-in hybrids at the Albany Street Garage on the campus of MIT, the Prudential Center, and 33 Arch Street in downtown Boston. In San Francisco, the prototype Prius PHVs are located at City Hall, Union Square, and Fisherman's Wharf. Portland gets two of the new plug-ins, and they can be found at the Portland State University Parking Garage and at Shaver Green. These cities and locations were selected because they already had existing charging infrastructure. An aftermarket converted plug-in Prius is already in the San Francisco fleet.

Working with private companies, universities, and organizations to fleet-test vehicle prototypes is common practice for manufacturers. Fleet tests deliver valuable feedback and data to the carmaker, which can lead to improvements and changes before the cars become available for sale to the public. But Zipcar is the first car-sharing arrangement to let any of its members take part in the process.

"Zipcar is an ideal test bed for early consumer acceptance of EVs," Scott Griffith, chairman and CEO of Zipcar, said in a news statement. "This project will allow companies to receive direct feedback from thousands of consumers in three cities and help evaluate how EVs fit into a large-scale car-sharing model."

Based on feedback from a large sample of users, many booked trips of fewer than 13 miles round trip, says Zipcar. Drivers of these short errand runs will take advantage of the plug-in Prius' all-electric range. But back-to-back rentals may mean that several drivers won't ever get to experience the uninterrupted all-electric drive. In that case, the Prius PHVs won't seem much different than the hundreds of conventional Priuses in Zipcar's nationwide fleet.

Zipcar added 8 Toyota Prius Plug-in Vehicle prototypes to a few of its Boston, San Fancisco, and Portland locations that members can rent by the hour as part of a test program with Toyota.