Bitmain Antminer S21 XP Immersion (300Th)

Two modes. NEM (Normal Efficiency Mode): 300 TH/s at 4,050W and 13.5 J/TH. HEM (High Efficiency Mode): 380 TH/s at 5,700W and 15 J/TH. ±3 percent hashrate and ±5 percent power tolerance. MM's product page lists only NEM specifications; HEM is entirely missing. Operator selects mode via firmware configuration based on desired output versus efficiency trade off.

No. MM's product page lists 100-240V universal single phase, but this is incorrect. The actual voltage is 220-277V single phase per Viperatech, Maxi Miners, and Bitcoin Merch, or 380-415V three phase per BT-Miners and CryptoMinerBros. At 4,050W on 120V the unit would draw 33.75 amps, exceeding any standard residential circuit. MM's claim of "rare single phase immersion capability" is built on a voltage specification that does not exist in Bitmain's official documentation. Verify actual voltage with MillionMiner before planning electrical infrastructure.

No. MM's body copy claims "No fans, no moving parts, no air filtration" and lists 50 dB noise. Actual specifications per Viperatech, Maxi Miners, Bitcoin Merch, and Asic Marketplace: four onboard cooling fans and approximately 76 dB noise. The fans continue operating submerged in dielectric fluid, agitating fluid around hashboards to improve heat transfer. The "zero fans, zero moving parts" narrative MM uses is counter to Bitmain's documented design.

Immersion cooling submerges the entire miner (boards, chips, PSU) into dielectric (non conductive) fluid inside a sealed tank. Dielectric fluids include Engineered Fluids BitCool, 3M Novec 7100/7500, Shell S5 X, Castrol ON, and mineral oil. The fluid absorbs heat from all component surfaces simultaneously and circulates to external heat exchangers or cooling towers. Unlike hydro cooling (closed loop water through a cold plate on the hashboard), immersion cooling exposes the entire hardware to the coolant for maximum heat transfer area.

Dielectric fluid tank ($2,000 to $10,000+ depending on capacity), dielectric fluid ($1,000 to $5,000+ per tank depending on volume and fluid type), circulation pumps ($500 to $2,000), external heat exchanger or cooling tower ($3,000 to $20,000 for industrial scale), plumbing and monitoring ($2,000 to $5,000). Total immersion infrastructure for a new single tank deployment: approximately $10,000 to $50,000. For operators without existing immersion infrastructure, this is substantial additional CapEx above the miner itself.

Yes (NEM mode). MillionMiner calculator at $0.08 per kWh in NEM mode: +$3.47 daily ($11.24 revenue minus $7.78 electricity). Monthly: +$104.10. HEM mode at +$3.29 daily produces more total Bitcoin at slightly lower margin. Immersion infrastructure costs must be amortized separately over your fleet deployment. For existing immersion facilities adding capacity, economics are straightforward miner-level calculations. For new immersion deployments, the full infrastructure amortization applies.

NEM (Normal Efficiency Mode): 300 TH/s at 4,050W producing 13.5 J/TH. More efficient per terahash. Default operating mode. HEM (High Efficiency Mode): 380 TH/s at 5,700W producing 15 J/TH. 27 percent more hashrate at 41 percent more power. Trade off: HEM produces more total Bitcoin per unit at worse efficiency. Operator selects based on electrical and cooling capacity, and electricity rate. At cheap electricity, HEM's extra hashrate captures more revenue. At expensive electricity, NEM's efficiency wins.

S21 XP Hydro at 473 TH/s, 5,676W, 12 J/TH, $6,899 (hydro cooled, closed water loop). S21 XP Immersion at 300 TH/s NEM / 380 TH/s HEM, immersion cooled (this product). The Hydro delivers more hashrate at dramatically better efficiency. The Immersion requires a different infrastructure (tank and fluid versus pumped water loop). For operators with existing hydro infrastructure, the S21 XP Hydro is generally the more efficient choice. For operators committed to immersion infrastructure, the S21 XP Immersion is the S21 generation immersion option.

S23 Immersion at 442 TH/s (newer generation, more hashrate, typically better efficiency, requires 380V+ three phase). S21 XP Immersion at 300 TH/s NEM / 380 TH/s HEM. The S23 Immersion is the next generation immersion product. For operators upgrading immersion facilities or adding new capacity, the S23 Immersion produces more Bitcoin per unit. The S21 XP Immersion is the older generation at potentially lower CapEx and with more flexibility in electrical infrastructure requirements.

No. Immersion deployment is mandatory. The hardware does NOT operate in open air. Bitmain designed the S21 XP Immersion specifically for dielectric fluid submersion, and the cooling configuration assumes fluid as the primary heat transfer medium. Attempting open air operation will cause rapid thermal failure. For air cooled Bitcoin mining, use the standard S21 XP (270 TH/s air cooled, $4,051) or S23 (318 TH/s air cooled, $8,103).

Standard data center and mining immersion fluids including Engineered Fluids BitCool, 3M Novec 7100/7500, Shell S5 X, Castrol ON, and mineral oil. Cost ranges from approximately $10 per gallon (mineral oil) to $200+ per gallon (engineered synthetic fluids). Choice depends on budget, thermal performance requirements, and warranty compatibility (some Bitmain warranty terms may specify approved fluids). Consult Bitmain warranty documentation for fluid compatibility specifications.

Approximately 76 dB from four onboard cooling fans. MM's claimed 50 dB is incorrect. Plus additional noise from external tank pumps (typically 50-60 dB) and heat exchangers. Total facility noise with immersion infrastructure is generally quieter than air cooled miner facilities at the same aggregate hashrate because the onboard fans run at lower RPM in fluid than in air, but the individual miner is not silent.

0 to 45 degrees Celsius inlet oil temperature per Viperatech, Maxi Miners, and Asic Marketplace. MM lists 5 to 45 degrees Celsius. Ambient air temperature is largely irrelevant because the dielectric fluid isolates the chips from ambient conditions. The relevant temperature is inlet fluid temperature, which should stay within this range for optimal operation.

Immersion cooling captures thermal energy far more effectively than air cooled exhaust. Heated dielectric fluid (typically 40-60 degrees Celsius outlet temperature) can be routed through heat exchangers to heat secondary systems: building HVAC, greenhouse cultivation, swimming pool heating, aquaculture facilities, or industrial process heating. The 4,050W NEM or 5,700W HEM heat output becomes a meaningful secondary energy resource rather than a pure cooling expense.

All SHA-256 proof of work cryptocurrencies. Bitcoin (BTC) primary. Bitcoin Cash (BCH), Bitcoin SV (BSV), eCash (XEC), Fractal Bitcoin (FB), and other SHA-256 chains. AuxPoW merged mining through compatible pools. Same coin compatibility as every S21 family miner.

BraiinsOS+ supports S21 series Antminer hardware including immersion variants. BraiinsOS+ autotuning can optimize efficiency further than stock firmware, potentially reducing the NEM mode from 13.5 J/TH toward 13.0 to 13.2 J/TH. Verify current BraiinsOS+ S21 XP Immersion compatibility on Braiins documentation. Vnish firmware is another third party option for Bitmain hardware.

Immersion deployment requires dielectric fluid tank, fluid, pumps, and heat exchangers already in place. Submerge the miner in the tank. Connect power cable to 220-277V or 380-415V service (verify your actual voltage requirement). Connect Ethernet cable. Start fluid circulation and verify flow. Find miner IP through Bitmain IP reporter, router DHCP, or network scanning. Configure SHA-256 pool and BTC wallet via Antminer web interface. Select NEM or HEM mode. Verify hashrate stabilizes at 300 TH/s (NEM) or 380 TH/s (HEM). Professional installation recommended for first time immersion deployments.

365 day Bitmain manufacturer warranty per BT-Miners and CryptoMinerBros. Among the longest warranties in the ASIC mining industry. Covers manufacturing defects and hardware failures under normal operating conditions. Warranty may be voided by use of non approved dielectric fluids, operation outside specified temperature range, or voltage errors. Consult Bitmain warranty documentation for specific fluid compatibility and operating condition requirements.

The S21 XP Immersion is a specific use case product for operators with immersion infrastructure. Buy if: you already have dielectric fluid tank and cooling infrastructure, you want Bitmain S21 family hardware at 300-380 TH/s in immersion form factor, you value the NEM/HEM dual mode flexibility for balancing efficiency versus absolute hashrate, or you need single phase immersion capability (verify 220-277V single phase support with MillionMiner, NOT 100-240V as MM lists). Do not buy if: you do not have or will not build immersion infrastructure (the miner does not operate in open air), you need the more efficient S21 XP Hydro (473 TH/s at 12 J/TH, $6,899) instead, you were sold on the 100-240V claim (false) or the 50 dB silent operation (false, actually 76 dB with four fans).

Within Bitmain immersion/hydro alternatives: S21 XP Hydro (473 TH/s, 12 J/TH, $6,899), S21 XP+ Hyd (500 TH/s, 11 J/TH, $9,500), S23 Immersion (442 TH/s newer gen), S23 Hyd (580 TH/s, 9.5 J/TH, $14,299). Air cooled alternatives: S21 XP (270 TH/s, $4,051), S21 PRO (234 TH/s, $3,083), S23 (318 TH/s, $8,103). For immersion infrastructure: MillionMiner stocks hydro radiators, racks, and mining containers adaptable for immersion facility builds. Canaan and Bitdeer alternatives: Bitdeer A3 Pro Hydro (660 TH/s, 12.5 J/TH, $10,449), Canaan A16XP (300 TH/s air cooled).