The carbon dioxide pollution caused by BTC mining is almost negligible compared with the traditional industrial carbon dioxide production!
Compared to the exploitation of oil, gold mining, BTC mining is very environmentally friendly!
I think electricity is not really a problem in Bitcoin mining because there are so many invention today that can really help our mother earth and in terms of electricty we can now use solar panels to generate electriciy and you don't need to burned trees or use gasoline that creates smokes.
Therefore, a technology that has the nature of interdependence, a technology can not stand alone without the existence of other technologies that can support it, as well as bitcoin mining, if this technology is combined with new technologies, especially in terms of alternative power supplies, the blockchain will become one of the most up-to-date technologies to use as the safest data storage and unmanageable by anyone except by its users.