Product Overview

The Bitmain Antminer S21+ 225Th is a high-efficiency SHA-256 Bitcoin (BTC) ASIC miner from Bitmain’s next-generation S21+ series. Delivering 225 TH/s at approximately 3,375W, the S21+ 225Th achieves approximately 15 J/TH power efficiency — competitive with the best air-cooled Bitcoin miners available. The “+” designation indicates this is Bitmain’s refined S21 platform with improved performance characteristics over the base S21 series.

The S21+ 225Th sits as the entry-level variant in the S21+ lineup, with the S21+ 235Th offering higher hashrate at similar efficiency. For South African Bitcoin mining operators, the S21+ 225Th represents a practical choice in the 225+ TH/s class — combining meaningful Bitcoin hashrate with Bitmain’s proven manufacturing quality, established firmware ecosystem, and compatibility with standard SHA-256 mining infrastructure.

At 3,375W, the S21+ 225Th requires dedicated 32A electrical infrastructure — placing it firmly in the commercial Bitcoin mining category. For operators running existing S21 Pro, S21 XP, or older S19-series hardware, the S21+ 225Th represents a compatible platform upgrade with strong efficiency characteristics.

Key Features

• 225 TH/s SHA-256 Hashrate (±3%): High-tier Bitcoin mining contribution per unit. At 225 TH/s, the S21+ 225Th delivers substantial pool contribution for commercial mining operations.
• ~15 J/TH Power Efficiency: Competitive air-cooled Bitcoin mining efficiency from Bitmain’s latest S21+ platform architecture.
• 3,375W Power Consumption: Industrial-grade power draw requiring dedicated 32A circuits and appropriate electrical infrastructure.
• Air-Cooled Industrial Design: Dual high-speed axial fans in a front-to-back airflow configuration for rack deployment in ventilated mining facilities.
• Noise Level ≤75 dB: Industrial noise levels requiring dedicated mining space.
• Bitmain Ecosystem Compatibility: Compatible with standard Bitmain mining management infrastructure, BTCTOOLS, and major SHA-256 mining pools.
• Standard Ethernet Management: RJ45 with web-based interface for pool configuration, monitoring, and firmware updates.

Technical Specifications

• Algorithm: SHA-256
• Supported Coins: Bitcoin (BTC), Bitcoin Cash (BCH), and other SHA-256 cryptocurrencies
• Hashrate: 225 TH/s (±3%)
• Power Consumption: ~3,375W (±5%)
• Power Efficiency: ~15 J/TH
• Cooling: Air-cooled, dual high-speed fans
• Noise Level: ≤75 dB
• Input Voltage: 200–240V AC, 50/60 Hz
• Networking: 1× RJ45 Ethernet
• Operating Temperature: 0°C to 40°C
• Power Supply: Confirm inclusion at time of purchase

Power & Installation Notes

The Antminer S21+ 225Th draws approximately 3,375W continuously. South African installations must comply with SANS 10142 with all circuits certified by a registered electrician. A dedicated 32A single-phase circuit is required. South Africa’s 230V / 50Hz supply is within the unit’s 200–240V input specification.

Load shedding at 3,375W is not manageable with residential inverter systems. Plan for downtime during load-shedding stages or invest in commercial generator capacity for uninterrupted operation.

Industrial ventilation is required — active extraction must maintain ambient temperatures below 40°C. The S21+ exhausts significant heat from its rear fans and requires directional airflow management.

Electricity Cost Context — South Africa

At R2.80/kWh reference tariff, the estimated monthly electricity cost is:

(3,375 ÷ 1,000) × 24 × 30 × 2.80 = R6,804 per month

This is an operating cost estimate only. Actual tariffs vary by municipality and supply type. At ~15 J/TH, the S21+ 225Th achieves approximately the same electricity cost per TH/s as the S21 Pro series, making it competitive in its efficiency tier.

Ideal Use Cases

• Commercial Bitcoin mining operations: The S21+ 225Th is designed for professional mining farms with industrial power supply and purpose-built facilities.
• Fleet upgrades from older S21 or S19 hardware: Operators upgrading S21 or S19-series hardware will find the S21+ platform offers competitive efficiency at higher hashrate.
• Capacity expansion in existing S21+ fleets: The S21+ 225Th uses the same S21+ platform as the 235Th variant, making it directly compatible with existing S21+ infrastructure.
• Commercial operations with renewable energy: South African mining operations with PPA or wheeling arrangements can leverage the S21+ 225Th’s efficiency to improve their mining economics.

Frequently Asked Questions

Does the Antminer S21+ 225Th work on South African power?
Yes. South Africa’s 230V / 50Hz supply is within the unit’s 200–240V input range. A dedicated 32A circuit certified by a registered electrician is required.

What is the difference between the S21+ 225Th and S21+ 235Th?
The S21+ 235Th offers 10 TH/s more hashrate at proportionally higher power. Both share the S21+ platform architecture and similar efficiency. Choose the 235Th for maximum hashrate; choose the 225Th if the 10 TH/s difference and slightly lower power matter for your operation.

What mining pool should I use?
Major SHA-256 pools include Foundry USA, AntPool, ViaBTC, F2Pool, and Binance Pool. Configure via the S21+’s web interface over your local network.

Can it handle load shedding?
Not on residential inverter systems. Commercial generator backup or planned downtime is required at ~3,375W.

Is the PSU included?
Confirm PSU inclusion at time of purchase.

What’s Included

• 1× Bitmain Antminer S21+ 225Th mining unit
• Power supply (confirm inclusion at time of purchase)
• Power cables
• Quick-start documentation