Bitcoin Energy Consumption Index - Digiconomist. Provides the latest estimate of the total energy consumption of the Bitcoin network.
A Proof of Stake Design Philosophy - Vitalik Buterin, critique by Tuur Demeester and follow up article. On Proof of Stake as an alternative to the energy-intensive Proof of Work in blockchain technology.
Nothing is Cheaper than Proof of Work - Paul Sztorc. On how alternatives to Proof of Work may not be more energy-efficient than proof of work.