[betterunix2]

Yes. Energy spent on Bitcoin is energy not spent on something else, even in a world where everything is powered by renewable energy. We do not live in a world where everything is renewable, and renewable energy spent on Bitcoin means whatever non-renewable power is being used elsewhere instead of being eliminated. It is also a myth that renewables have no negative environmental impact: metals have to be mined/smelted/etc., chemicals of various kinds are used, and there is waste from the manufacturing processes. Ideally we would be working towards more efficient technologies that use less energy to accomplish whatever task (and for the most part we have been doing that).