Start with two compatible observations
To calculate J/TH, divide power in watts by hashrate in TH/s. The time units cancel because a watt is a joule per second. A fictional 200 TH/s device drawing 4,000 W therefore has an illustrative ratio of 20 J/TH.
The arithmetic is straightforward; the measurement boundary is where care matters. Confirm whether power is measured at the device, rack, or site, and pair it with hashing work over a compatible interval.
Do not average device ratios blindly
Consider a fictional 100 TH/s device drawing 2,000 W and a 200 TH/s device drawing 5,000 W. Their combined ratio is 7,000 ÷ 300, or about 23.33 J/TH. A simple average of their individual ratios would give a different, misleading fleet result.
The complete J/TH guide explains this example, stopped workers, missing observations, and reproducible test records.
Keep “undefined” visible
When hashrate is zero, the individual power-to-hashrate ratio is not a finite usable efficiency value. Display an explicit unavailable state. Missing telemetry also must not silently become zero.
For whole-fleet energy accounting, consumption by stopped equipment still matters if it is inside the defined boundary. A calculation that excludes troubled equipment can create an attractive but incomplete result.
Design a controlled comparison
Use supported configurations, comparable conditions, and a documented observation interval. Record the baseline and preserve a recovery path. Change only what the test is intended to compare, and keep unsuccessful or inconclusive runs.
A lower ratio does not automatically justify purchasing equipment or changing an operating profile. Include useful work, stability, installation constraints, and the scope of the actual decision.
Follow the energy into the bill
Energy efficiency is one input to a broader cost model, not a profitability guarantee. The electricity guide converts power and time into energy-only examples with explicit assumptions. The cost-planning page separates installation, recurring expenses, and uncertain scenarios.
For a practical next step, open the monitoring demo and reproduce its displayed efficiency ratio directly from the bundled fleet and worker files.