Bitcoin’s energy efficiency has been a concern over the years as mining activities consumed rather massive amounts of electricity. 
Part of this resulted from the machines miners use, which have a high energy consumption.
According to a new report by Coinmetrics, three Bitcoin mining rig models account for 76% of the Bitcoin network’s computing power. 
The report also revealed that Bitcoin’s energy efficiency has improved drastically in the past five years. …
Read More: New Research: Bitmain’s S19 Miners Hold Majority of Bitcoin Network Hashrate