Estimates cost for mining 1 bitcoin on a recent hardware

estimate-1-btc-mining-cost.py

#!/usr/bin/python
el_cost_usd = 0.035
# network difficulty
ndiff = 15958652328578.91
block_reward = 6.25
# S9 with AB enabled consumes ~13% less energy (assuming 4-midstates enabled for AB)
# Below is a favorite overclocked configuration (15.6 Th/s , 1331 W)
efficiency_w_per_ths = 85.3
# S9: heavily downclocked
# efficiency_w_per_ths = 71

efficiency_kw_per_hs = efficiency_w_per_ths * 1e-3 * 1e-12
cost = el_cost_usd * efficiency_kw_per_hs * ndiff  * (1<<32) / (block_reward * 3600)
print('Cost for mining 1BTC is %.2f (electricity rate USD %.2f/kWh)' % (cost, el_cost_usd))

estimate-total-network-power.py

# 14 TH/s (e.g. S9)
single_hashrate = 14e12
# average power consumption with S9 and AB enabled
power_kw = 1.372 * 0.87
# network difficulty
ndiff = 5646403851534.72
total_hashrate = ndiff * (1<<32) / 600
total_power_gw = power_kw * 1e-6 * total_hashrate / single_hashrate
print('Rough estimate of network power %.3f GW' % total_power_gw)