I agree with some of the sentiment of the article, bitcoin's energy consumption is something to keep an eye on and if we can seamlessly move to an algorithm that's greener then so be it but you have to realize the tremendous amount of good that bitcoin is doing for the world and will likely continue to do as it becomes scarcer and scarcer, don't knock a technology that can single handedly lift a continent like Africa out of poverty.
*edit: Nothing like defending bitcoin on Hacker News and getting downvoted to oblivion, hey rather than downvote why don't you point out exactly what you disagree with so we can have a discussion