Skip navigation to main content.
NREL - National Renewable Energy Laboratory
About NRELEnergy AnalysisScience and TechnologyTechnology TransferTechnology DeploymentEnergy Systems Integration

Indianapolis Public Transportation/Knoxville Area Transit

Photo of IndyGo hybrid bus.

Knoxville Area Transit transports passengers in one of four 22-foot hybrid electric trolleys manufactured by Ebus and equipped with propane Capstone MicroTurbine auxiliary power units.

In 2004, the Fleet Test and Evaluation team worked with Indianapolis Public Transportation (IndyGo) and Knoxville Area Transit to study hybrid electric buses manufactured by Ebus and equipped with Capstone MicroTurbine auxiliary power units.

The 6- to 12-month evaluation focused on the performance of five diesel hybrid buses at IndyGo and four propane hybrid trolleys at Knoxville Area Transit. IndyGo operates 230 buses and paratransit vehicles in Indianapolis, Indiana, and transports more than 8.7 million passengers each year. Knoxville Area Transit runs 80 buses, paratransit vehicles, and trolleys in Knoxville, Tennessee, and transports 3.2 million passengers each year.

The results of this study are featured in Case Study: Ebus Hybrid Electric Buses and Trolleys.

Additional information on Ebus/Capstone is available on the Hybrid Electric Drive Systems Publications page.