> These costs and power requirements are not obvious At the time of payment they are irrelevant. > Any comparison between cash and non-cash needs to be sure t

> These costs and power requirements are not obvious At the time of payment they are irrelevant. > Any comparison between cash and non-cash needs to be sure to count the complete lifecycle of and payment processing and not just the bits that the end-user sees. Where is it convenient for you to draw the line? Do you include the production of card readers, the creation and maintenance of power and communication lines?