This is an excellent analysis, but I would end it with the statement: "Bitcoin will constantly and provably use more energy until it doesn't." The mining infrastructure has been supported by seniorage, or the printing and distribution of new bitcoins to miners at a very high double-digit inflationary rate. Bitcoin adherents talk about the currency as if it has already entered the "paradise" state of zero money growth. It hasn't, and as it approaches that state and miners stop earning enough to pay for their electricity, the hashrate will either fall precipitously or transaction fees will have to be dramatically increased.