I 'll also notice what the whole experiment proved: That money can perverse moral incentives. The electricity/wasted energy issue you mention is just one of them. The amount of time spent on building and specializing the hardware is another. All this was in the hope of the abstract goal of creating money, not wealth. People weren't so zealous in building specialized hardware for, say, protein folding. Bitcoin advocates usually put forward "the good of humanity" argument, yet the product by design puts individual interests above all other interests.