%0 Conference Paper %A Kristen Ardani %A Galen L Barbose %A Robert Margolis %A David Feldman %B 2012 38th IEEE Photovoltaic Specialists Conference %C Austin, TX, USA %D 2012 %I IEEE %P 001762 - 001767 %R 10.1109/PVSC.2012.6317935 %T Quantifying non-hardware balance of system costs for photovoltaic installations in the United States using a combined annual expenditure-labor hour productivity approach %8 06/2012 %@ 978-1-4673-0064-3