'Plug-In Ecosystem' Available at Indiana Mall Electric car owners who visit the Clay Terrace mall in the Indianapolis suburb of Carmel can connect to a charging station that taps into energy from the sun. On Jan. 30, the mall cut the ribbon on a "Plug-In Ecosystem" that combines solar power, a large storage battery and both Level II and Level III chargers. For the time being, the electricity is free. There should be no shortage of electric vehicles to charge at the station, which is close to Whole Foods and Starbucks outlets. Paul Mitchell is president and chief executive of Energy Systems Network, a nonprofit industry consortium that includes Project Plug-IN, which started in 2009 and has worked to increase the number of electric vehicles on state roads. Mr. Mitchell said in a telephone interview that there were probably more than 1,000 plug-in cars in Indiana, including 150 Think battery cars that were briefly assembled in the state and provided to local residents at substantial discounts. He also said there were about 100 public charging stations in the Indianapolis area. In December, Mayor Greg Ballard of Indianapolis signed an executive order requiring that any new purchases for its nonpolice car fleet of about 500 vehicles be battery electric or plug-in hybrid. The city wants to electrify its entire fleet by 2025 and is exploring the concept of a plug-in hybrid police vehicle, the mayor's office said in a news release. Partners in the Carmel charger include the mall owner Simon Property Group, Duke Energy, Toshiba, the Itochu Corporation and Energy Systems Network. Mr. Mitchell said the pilot system was designed in part to reduce the major impact that 480-volt fast charging could have on the electric grid. Cars using the Level III Eaton fast charger will get the power from the grid, he said, but the 10-kilowatt solar panels would generate electricity to be stored in the 42-kilowatt-hour Toshiba battery. That battery power can be withdrawn by Duke Energy to offset the charger's load. The system also includes two 240-volt Level II Siemens chargers that don't draw as much energy. The Carmel system has the potential to eliminate the need for a larger and costlier utility transformer, Mr. Mitchell said. "Indianapolis is a sandbox for technology companies from around the world," he said. Toyota, Energy Systems Network and Duke Energy are also working on a 12-month pilot project in central Indiana to test a new grid communications system. The system, installed on five Prius Plug-in Hybrids driven by Duke Energy customers, can interact with the utility provider and charge the car only during off-peak lower price periods. George Caraghiaur, senior vice president of sustainability at Indianapolis-based Simon Property Group, was unavailable for comment, but he said in a statement, "The majority of our shopping malls across the state are now equipped with electric vehicle charging stations, and we're seeking to upgrade this infrastructure just like we work to enhance every aspect of our customers' shopping experience."