This model was proposed by @paulewaulpaul as an attempt to model the cost of BTC production using Difficulty (input) and Issuance (output) as the key parameters. The following is paraphrased from the original research piece:

Difficulty D is taken as the estimated number of hashes required to mine a block (denoted in raw hashes). This is proportional to the energy consumption and the energy efficiency and reflects the demand. We use difficulty to estimate production costs. As mining becomes more efficient over time, hash rate becomes cheaper. Therefore we add a damping coefficient k and a scaling factor a (the cost per unit of adjusted difficulty). To get the value per coin, we divide by the issuance I. We get the values for a and k by fitting the function to price. For this we use the lows of the last two halving cycles, deep in the bear market when only the most efficient mining was profitable.

The PoW Floor Model is thus calculated as follows: PoW Floor Pricing Model = 2/3 * (sma(D,180)^0.41 / sum(I,180))

The damping coefficient is k = 0.41 and scaling factor a = 2/3. Statistically, this means that doubling the difficulty increases the estimated production cost by ~33%. We use a moving average for the difficulty and look at a 180 day period. For the upper bands we use the 1.41 and 2 multiples where the factor of 2 estimates the cost of production after the next halving event (assuming constant difficulty).

Coined By

kuntah in Bitcoin: Difficulty per Issuance - A PoW Pricing Model, Oct 2022