2 March 2026
The Power Math Behind Keeping Older Flagships Online
A straightforward break-even framework for deciding whether your 0.05 TH/s-and-above legacy miners still earn their electricity bill.
Operators ask us the same question every quarter: should I keep running these machines? The answer is arithmetic, not sentiment. Here is the framework we use in every power efficiency audit.
The Basic Formula
Daily revenue = (Your hash rate in TH/s ÷ Network hash rate in TH/s) × Block reward × Blocks per day × Coin price
Daily cost = (Power draw in kW) × 24 hours × Electricity rate in ₩/kWh
When daily revenue exceeds daily cost, the machine earns its place. When it does not, tuning may close the gap — or it may be time to unplug.
Why Tuning Changes the Equation
A stock Antminer S9 at 14 TH/s and 1,372W costs ₩2,959 per day at ₩90/kWh. Tuned to 12 TH/s and 1,000W, that drops to ₩2,160 — a 27% savings. If your tuned hash rate still participates meaningfully in pool revenue, the lower power draw extends viability by months.
The critical variable is how much hash rate you sacrifice. A 15% power reduction paired with a 14% hash-rate loss is nearly break-even on electricity alone. You need power savings to outpace hash-rate decline.
Difficulty Trends
Network difficulty rises over time, reducing your share of block rewards even if your hash rate stays constant. Our 90-day outlook memos model three scenarios: flat difficulty, historical average increase, and aggressive increase. Conservative operators plan for the middle scenario.
The 0.05 TH/s Floor
We focus on machines at 0.05 TH/s and above because below that threshold, even aggressive tuning rarely produces enough revenue to justify rack space, cooling, and maintenance attention. Units like the Antminer S7 (4.73 TH/s) belong in a museum, not a production rack — unless your electricity is essentially free.
Getting Your Numbers
You need three measurements: actual watt draw at the PDU (not nameplate), pool-reported 24-hour average hash rate, and your all-in electricity rate including demand charges. Contact us for a power efficiency audit if you want these calculated across your entire fleet with break-even projections included.