The fundamental flaw in the argument in comparison to Visa or MasterCard is the fact they don’t take into account the energy consumption of the entire organization.

Visa/MasterCard employ tens of thousands of employees (maybe more). Each of those employees have to drive to work everyday, consuming energy. Then sit in brightly lit office buildings, each running a computer sucking down power.

Those buildings have to be built, using time energy and resources.

Without taking into account all of the energy overhead required for these organizations to function the argument is meaningless.

If cryptotocurrencies continue down this path, it’s quite likely these types of organizations could cease to exist. Resulting in a huge energy savings.

It’s also extremely likely crypto currencies will reduce energy consumption by moving to more efficient transaction validation methods like Proof of Stake