A simpler way to see the issue is through bullet points of both the optimistic side as well as pessimistic side.
A few months ago the Token Economy email newsletter did just this and provided this awesome list of pessimistic/optimistic takes on Bitcoin's energy use. I'll share then with you here:
Pessimistic view:
- Bitcoin uses as much energy as 520,000 Canadians every day
- Bitcoin uses as much energy as the Democratic Republic of Congo
- Bitcoin uses more energy than 116 countries each
Optimistic view:
- The energy that Bitcoin consumes in a year would only last the U.S. for 19 hours.
- Bitcoin uses only 20% of the energy from a single coal power plant in Taiwan
- The Three Gorges Damn in China produces three times as much electricity as Bitcoin consumes
- The U.S. produces more electricity from a single Geothermal plant than Bitcoin requires
- 17 NSA Data centers together consume more electricity than Bitcoin
- Google used about double as much electricity in 2015 than Bitcoin does today
- Bitcoin miners will consume an estimated 8.27 terawatt-hours per year, but that's less than the estimated 11 terawatt-hours per year to produce the global cash and coin supply, while gold mining burns the equivalent of 132 terawatt-hours - and that doesn’t include armored trucks, bank vaults, security systems and such.
