Foreword
This evaluation would not have been possible without the support and guidance from staff at
Washington Metropolitan Area Transit Authority, including the following:
" Jack Requa
" Phillip Wallace
" Robert Golden
" Sebastian Silvani (contractor from Booz Allen Hamilton)
" Barry Goldman
" John Smith.
The authors wish to acknowledge the leadership and input from Dennis Smith at the U.S.
Department of Energy, and the contributions to this evaluation from New Flyer, Cummins
Westport, Inc., John Deere, and Hanover.
This report is available from the National Renewable Energy Laboratory in PDF at
www.nrel.gov/docs/fy06osti/37626.pdf.
Kevin Chandler and Erin Eberts              Margo Melendez
Battelle                                    National Renewable Energy Laboratory

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