I feel like screaming With this statement I have downgraded my understanding of BTC to 1%I hope in future we'll figure out an algorithm that avoids the intense work.
I thought the proof-of-work was completely flexible, the difficulty level is adjustable. If an easier algorithm was used we would need to adjust its difficulty level to get the same result. I thought the object was to target that it would need 10 mins on average for the whole mining power to add the next block. It is the combination of the 10 min requirement and the current mining power that determines the electricity usage. This is independent of the algorithm that got that result, I thought.