Bitmain · 2024
Antminer S21 Hydro
Water-cooled density for facilities, not garages.
Hashrate335 TH/s
Efficiency16 J/TH
Wall power5,360 W
Coolinghydro
Noisen/a (liquid)
Released2024
Energy $/day @ $0.10/kWh$12.86
The longer story
The S21 Hydro trades plug-and-play for density: water cooling lets it pack more hashrate per unit and run quieter, but it presupposes a facility with hydro loops, dry coolers and the plumbing expertise to run them. This is infrastructure, not an appliance.
It suits industrial deployments already built (or building) for liquid cooling — where the density and heat-reuse economics genuinely change the math. For anyone without that infrastructure, the air-cooled S21s deliver the same silicon without the plumbing.
Quick answers
- How efficient is the Antminer S21 Hydro?
- The Antminer S21 Hydro runs at 16 J/TH — joules per terahash is the number that decides mining profitability. Water-cooled density for facilities, not garages.
- How much power does the Antminer S21 Hydro use?
- Typical wall draw is 5,360 W, which at a reference $0.10/kWh costs about $12.86 per day in electricity. Scale linearly to your own rate — the electricity price is the whole business.
- Is the Antminer S21 Hydro suitable for home mining?
- No — it is hydro-cooled and assumes facility infrastructure (liquid loops, dry coolers).
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