[logancg]

A thought experiment: how much energy should Bitcoin use?

Bitcoin's mkt cap is ~$140B [0]. The world's GDP is ~$127T [1]. If we assume: 1) BTC market cap is representative of its economic output in accounting terms, or is at least an upper limit 2) Energy use by product should be proportional to its output

Then at 0.11% of world output, Bitcoin is at least ~5x more energy intensive per unit of value than the average product.

(This is obviously not wholly accurate. For one, market cap != annual value. If accounted for, that might make Bitcoin several orders of magnitude less efficient. And assumption 2 is probably a linear approximation to a highly nonlinear relationship. But I propose this as a fun thought experiment that questions the energy-value relationship.)

[0] https://coinmarketcap.com/currencies/bitcoin/ [1] https://www.cia.gov/library/publications/the-world-factbook/...

[ThrustVectoring]

Market cap has completely different units than GDP - dollars versus dollars per year. Your analysis is pretty much nonsense.

[logancg]

Totally agreed. For the thought experiment, make the super liberal assumption that most value was produced and realized in the past year (or a single year), and it becomes comparable. Otherwise, the inefficiency is a hard lower limit. So in the extreme case, the lower bound is 5x inefficiency. If we assumed a value equivalent to 1-5% of market cap is realized every year, it becomes 100x to 500x inefficient.

[AgentME]

>A thought experiment: how much energy should Bitcoin use?

If it used proof-of-stake, then it should be a negligible amount compared to what it uses now.

(Disclaimer: proof-of-stake is still being researched. Many altcoins presently claiming to be proof-of-stake rely on centralization (peercoin), likely have issues, and/or are underverified. I'm cautiously optimistic about the Ethereum community's thorough research into proof-of-stake.)