[hkt]

True, but the author is highlighting bitcoin as being a massive net contributor to CO2 emissions on a significant growth trend. It gets reported as "Bitcoin now uses more energy than $country" every once in a while now:

https://www.theguardian.com/technology/2017/nov/27/bitcoin-m... https://www.bbc.com/news/technology-56012952

That differentiates it from air travel, cement, etc. It is a worrying trend, even more so than the prosaic stuff.

Again, I don't disagree with the point you are making, but it seems remiss not to highlight the worst offenders.

[Ulrich2]

Fully agree. Interesting enough, global CO2 certificates would not affect Bitcoin at all (unlike air travel and cement). In the case of Bitcoin they would simply mean that the price per hash rate goes up for everyone, and therefore the difficulty is reduced.

So... if Bitcoin can push politics to make better, more air(!)-tight rules for CO2 certificates faster, then it would be clearly have a net benefit for the world.