Material and energy costs associated with open-source optics component fabrication compared to commercial prices and percent savings.

Notes:
aThe price of 3 mm ABS filament is $0.038/gram [3D Printer Stuff. Available: http://www.3dprinterstuff.com/shop/page/4?shop_param=Accessed 2012 Oct 19.].
bThe national average cost of electricity is 11.53cents/kWh [US Energy Information Administration. Available: http://www.eia.gov/beta/enerdat/#/topic/7?agg=0,1&geo=g&endsec=vg&freq=A&start=2008&end=2011&charted=1 Accessed 2012 Oct 19.] and the electricity cost was derived from multimeter is 0.006925 kWh/gram (using 3 mm ABS) assuming a Prusa RepRap 3-D printer.
cCommercial prices were derived from website data from various vendors including: Edmund Optics, Thorlabs, McMaster-Carr, AutoMate Scientific, and Pasco.