The global hash rate (in terahashes), block reward, and blocks per hour.
Global Hash Rate: 169.29 TH/s
Block Reward: 3 ETH
Blocks/hour: 240
The best consumer mining rig's hash rate and energy consumption.
Device Name: GTX1070 (6)
Hash Rate: 0.000192 TH/s
Energy Consumption: 1.10 kW/h
The average industrial cost per kilowatt hour of electricity.
Energy Cost: $0.07 kW/h
ĥ = global hash rate (TH/s)
ĥm = individual miner's hash rate (TH/s)
em = individual miner's energy consumption (kWh)
c = energy cost (kWh USD)
β = blocks per hour
r = block reward (btc)
m = total number of simulated miners
cmb = energy cost per miner per block (USD)
v = ethereum intrinsic value (USD)
First, find the total number of simulated miners m in the best case scenario (all using best combination of hash rate and energy consumption).
Second, find the energy cost per miner per block cmb in kilowatts-per-hour by dividing the energy consumption of an individual miner in kWh by the number of blocks found in an hour, and then multiplying the result by the constant cost of each kilowatt hour.
$$m = {ĥ \over ĥ_m}, c_{mb} = c{e_m \over β}$$
Finally, the lower bound on the intrinsic value of a coin's generation is the total system energy cost per block divided by the number of coins generated per block.
$$v = {m \times c_{mb} \over r}$$
With 881,725 miners and an individual energy cost of $0.000 kW/h the system energy cost per block is $279. Since the current block reward is 3 ETH then the energy cost per coin is $93.08.
A more detailed description is available in this blog post: A Bitcoin Valuation Experiment.
The energy cost to create a Bitcoin is akin to the cost of digging up and processing ore as if it were it a piece of metal.
We can see how much of Ethereum's price might be speculation.
Market Value
Intrinsic Value
Extrinsic Value
Speculation