I've noticed this too, and it's not just small blogs or comments either, in recent weeks I've noticed a few articles about the energy requirements of Bitcoin mining cropping up in the New Scientist, The Guardian, and the BBC.

https://www.newscientist.com/article/mg23631504-500-bitcoin-mining-uses-more-energy-than-ecuador-but-theres-a-fix/

https://www.newscientist.com/article/mg23631503-300-bitcoin-what-a-waste-of-resources/

https://www.theguardian.com/commentisfree/2017/nov/26/trouble-with-bitcoin-big-data-huge-energy-bill

https://www.theguardian.com/technology/2017/nov/27/bitcoin-mining-consumes-electricity-ireland

http://www.bbc.co.uk/news/technology-42265728