If Visa had a similar energy efficiency to bitcoin, the energy use of Visa alone would be larger than the current global energy use.
This rules out unaccounted dependencies hiding a larger energy use than reported for the financial sector that would put bitcoin on a more even footing, even when you count things like "the US military" or "extracting oil to fuel cars" as an energy cost solely existing for the financial sector.
Is it 1/200 of global financial activity?
Coindesk indicates that bitcoin had 25 million transactions versus Visa having 50 billion transactions. So that is 1/2000 [https://www.coindesk.com/what-bloomberg-gets-wrong-about-bit...]
If Visa had a similar energy efficiency to bitcoin, the energy use of Visa alone would be larger than the current global energy use.
This rules out unaccounted dependencies hiding a larger energy use than reported for the financial sector that would put bitcoin on a more even footing, even when you count things like "the US military" or "extracting oil to fuel cars" as an energy cost solely existing for the financial sector.