Bitmain Antminer S21 Immersion (301Th)

Taux de hachage 301.0 TH/s Puissance 5,569 W Efficiency 18.5 J/TH

Bitdeer SealMiner A3 Hydro

Taux de hachage 500.0 TH/s Puissance 6,750 W Efficiency 13.5 J/TH

Bitmain Antminer S21 Immersion (301Th) vs Bitdeer SealMiner A3 Hydro

Side-by-side specs, profitability, and home mining comparison.

Specifications Comparison

Bitmain Antminer S21 Immersion (301Th)	Specification	Bitdeer SealMiner A3 Hydro
301.0 TH/s	Taux de hachage	500.0 TH/s
5,569 W	Consommation électrique	6,750 W
18.5 J/TH	Efficiency	13.5 J/TH
50 dB	Niveau de bruit	50 dB
17.2 kg	Weight	20.5 kg
19,001 BTU/hr	BTU Output	23,031 BTU/hr
44/100	Home Mining Score	44/100
—	Release Year	—
SHA-256	Algorithme	SHA-256
Bitmain	Manufacturer	Bitdeer

Profitability Comparison

Electricity Rate:

$/kWh

Bitmain Antminer S21 Immersion (301Th)

Daily Revenue 0.00013852 BTC $10.83

Daily Electricity -$13.37

Daily Profit -$2.54

Monthly -$76.08

Yearly -$925.67

Bitdeer SealMiner A3 Hydro

Daily Revenue 0.00023009 BTC $17.99

Daily Electricity -$16.20

Daily Profit $1.79

Monthly $53.68

Yearly $653.08

Based on BTC price of $78,183 and current network difficulty as of May 16, 2026. Actual results vary.

Verdict

Weighing six performance factors, the Bitdeer SealMiner A3 Hydro comes out ahead — it takes 2 of 4 (efficacité, hashrate). The standout gap is 66% more hashrate (301 vs 500 TH/s) in the Bitdeer SealMiner A3 Hydro's favour. That said, the Bitmain Antminer S21 Immersion (301Th) isn't beaten everywhere — it still wins consommation électrique and rapport qualité-prix. Review the detailed specs and profitability calculations above to determine which miner best fits your specific setup.

Winner: Bitdeer SealMiner A3 Hydro — l'emporte sur 2 des 4 facteurs

Spec Deltas

Stripped to the numbers, this is how far apart the Bitmain Antminer S21 Immersion (301Th) and Bitdeer SealMiner A3 Hydro sit on each measurable spec:

Bitdeer SealMiner A3 Hydro 66% more hashrate (301 vs 500 TH/s)
Bitmain Antminer S21 Immersion (301Th) 17% better power draw (5,569 vs 6,750 W)
Bitdeer SealMiner A3 Hydro 27% better efficacité (18.5 vs 13.5 J/TH)
Bitmain Antminer S21 Immersion (301Th) 16% better weight (17.2 vs 20.5 kg)
Bitdeer SealMiner A3 Hydro 21% more heat output (19,001 vs 23,031 BTU/hr)

Cost & ROI Over Time

A miner pays for itself in profit, not specs. These projections track upfront cost against one, two and three years of net earnings at $0.10/kWh.

Bitmain Antminer S21 Immersion (301Th)	Metric	Bitdeer SealMiner A3 Hydro
$3,333	Upfront cost (MSRP)	$6,650
-$2.54	Daily net profit	$1.79
-$4,258	Net after 1 year	-$5,997
-$5,184	Net after 2 years	-$5,344
-$6,109	Net after 3 years	-$4,691
Does not pay back at current rates (negative daily profit)	Payback period	Takes ~10.2 years to pay back at current rates

Projections assume continuous operation, a flat $0.10/kWh rate, and no hardware degradation, pool fees, or BTC price change. Real-world ROI varies.

Best For...

Best for Profitability

Bitdeer SealMiner A3 Hydro

$4.33/day higher profit at current rates.

Best for Home Mining

Tie

Both miners are equally suitable for home use.

Best for Efficiency

Bitdeer SealMiner A3 Hydro

13.5 J/TH — lower electricity cost per terahash.

Frequently Asked Questions

Is the Bitmain Antminer S21 Immersion (301Th) or Bitdeer SealMiner A3 Hydro more profitable?

At the current BTC price and a $0.10/kWh electricity rate, the Bitdeer SealMiner A3 Hydro is more profitable at $1.79/day compared to $-2.54/day for the Bitmain Antminer S21 Immersion (301Th). Profitability depends heavily on your electricity rate — use the selector above to calculate with your actual costs.

Which is quieter, the Bitmain Antminer S21 Immersion (301Th) or Bitdeer SealMiner A3 Hydro?

Both miners have similar noise levels. Check the specs table above for exact decibel readings.

Bitmain Antminer S21 Immersion (301Th) vs Bitdeer SealMiner A3 Hydro: which fits a residential setup better?

Both miners score similarly on our Home Mining Score. Consider your specific constraints (noise tolerance, available power, heat needs) to decide.

What is the efficiency difference between Bitmain Antminer S21 Immersion (301Th) and Bitdeer SealMiner A3 Hydro?

The Bitmain Antminer S21 Immersion (301Th) runs at 18.5 J/TH while the Bitdeer SealMiner A3 Hydro runs at 13.5 J/TH — a difference of 5.0 J/TH. Lower efficiency means less electricity per terahash of mining power, directly reducing operating costs. In relative terms that is 27% better efficacité (18.5 vs 13.5 J/TH).

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