Bitcoin miners in combination pay for electrical energy to course of blocks of transactions, and the variety of blocks is predictable (one each 10 minutes or so). The calculable metric is consumption (of electrical energy or water) per block. Every block can include one or hundreds of transactions, relying on demand and measurement (by way of reminiscence consumption). At present, there are round 3-4,000 transactions per block, however earlier this yr, the quantity was extra like 1,000.