... system [1- 5 ,11 ,13 ,24,34, 51, 54]. A value of 1 is International Journal of Energy and Environment (IJEE), Volume 2, Issue 1, 2 011 , pp .1- 38 ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2 011 International ... production of hydrogen. 1. Net energy consumption: Energy requirement of the element to bring it to the point of use and energy required for operation of processes [20,24,30, 31, 36,39, 51, 54,60,68,76,82]. ... Hydrogen Energy 2008;33:6804-6839. International Journal of Energy and Environment (IJEE), Volume 2, Issue 1, 2 011 , pp .1- 38 ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2 011 International Energy...