It can take up to 81 minutes, as I write this, to complete a single bitcoin transaction. (globalcoinreport.com)
With the help of these numbers, it is possible to compare both networks and show that Bitcoin is extremely more energy intensive per transaction than VISA (note that the chart below compares a single Bitcoin transaction to 100,000 VISA transactions). (digiconomist.net)
A single bitcoin transaction can take up to 10 days to process, and the value of a single bitcoin varies depending on which exchange a user conducts their transaction through, according to the report. (links2exchange.net)