This gives us an energy consumption minimum for the Tezos network of about 10.5MWh per year, and a possible (though difficult to measure) likely maximum in the range of 350MWh/year. We presume the real answer lies somewhere between; a geometric mean of these numbers is about 60MWh/year. However, this is so much less energy than is consumed by popular Proof of Work-based cryptocurrencies that the distinction between these numbers, though large, matters relatively little. Whichever is selected, the difference in energy used is stark. Furthermore, as we note elsewhere, the Tezos network is unlikely to require substantially more energy as it grows, evolves, and gains value. Indeed, thanks to technical improvements, it may require significantly less energy over time.