Doing some back of the envelope calculations..<p>Hash rate is about 1,200 PH now. The most efficient ASIC miner today is the AntMiner S7 [1], which does 4.86 TH at 1.21 KW. This gives us a power consumption of the entire Bitcoin network of at least 300 MW. Actual power will easily be double that, given that not everybody is using the latest miner. So let's say total power consumption is about 600 MW. This is the output of a small power plant.<p>[1] <a href="https://www.bitcoinmining.com/bitcoin-mining-hardware/" rel="nofollow">https://www.bitcoinmining.com/bitcoin-mining-hardware/</a>