The POS switch has been in the works for several years (Ethereum co-founder Vitalik Buterin wrote about the idea as early as 2013), but only recently received a hard date earlier this year. That date, though still somewhat tentative, is Sept. 19.


If all goes according to plan and Ethereum’s success switches to POS on that date, the environmental issues surrounding cryptocurrency won’t suddenly dissolve away. Bitcoin, the leading cryptocurrency, still relies on POW, something that’s not likely to change, and countless other smaller proof-of-work coins also exist. That said, Ethereum’s the second largest blockchain so an energy consumption reduction that comes even close to what POS advocates would mark an important, consequential shift.