Production is only relevant if you divide by the number of transactions a bill or coin can be used in. Bitcoin miners must compute at least one new block befor

Production is only relevant if you divide by the number of transactions a bill or coin can be used in. Bitcoin miners must compute at least one new block before a group of transactions can be committed to the block chain. For physical money the energy spent per transaction is relatively low, basically the energy spent opening a cash register drawer or for a large transaction the energy spent by a counting machine. I suspect that paper money is far more efficient than Bitcoin, just given the amount of power Bitcoin consumes and the tiny number of transactions processed in a given time period by the Bitcoin system (tiny compared to the number paper money/coin that occur in a given day and basically irrelevant compared to the number of electronic payments made every day).