Bitmain Antminer S9
- Hashrate
- 13.5 TH/s
- Power
- 1,350 W
- Efficiency
- 100 J/TH
- Noise
- 76 dB
Industrial Space heater Unknown
A loud, workshop-style 'industrial' bitcoin heater from 21energy: 1.1–2 kW of heat for spaces up to 80 m² with up to 24 TH/s of older, less efficient mining hardware. Plug-and-play on a 16 A, 230 V socket. Currently sold out at half price.
Best price $694
$28.92 per TH · New · Out of stock at 21energy · excl. tax
50% off (was EUR 1,247.50 excl. VAT)
| Store | Trustpilot | Condition | Availability | Listed price | In your currency | Per TH | Checked | Link |
|---|---|---|---|---|---|---|---|---|
| 21energy Ships from Austria · Maker's own shop 50% off (was EUR 1,247.50 excl. VAT) | TrustScore 4.8 out of 5, 1,194 reviews | New | Out of stock | €624 excl. tax | $694 | $28.92 | 4 Nov 2026 | Visit |
Prices as listed on each store's page on the date shown, without shipping. Prices marked excl. tax leave out VAT or sales tax, and others may too. Per TH uses the hashrate of the unit each store sells. Converted at ECB rates of 11 Nov 2026. Trustpilot scores are for the store, not the device. Each store's name opens its page, with everything it sells and its reviews.
The maker gives no hashrate for this mode, so we can't work out its mining income.
*What a pool would pay on average at today's difficulty, block reward and bitcoin price, before pool fees. Solo miners usually earn nothing, and very rarely a whole block. A plain electric heater turns the same electricity into the same heat, so the mining income is what makes the difference.
Payback is how long the bitcoin a device earns takes to add up to its price. It leaves out electricity, which buys the heat: compare earnings per kWh with your electricity price to see whether mining alone covers it. It uses the average of the last 3 months, to 12 Nov 2026: bitcoin at $79,558, 969 EH/s on the network and 3.15 BTC a block, less a 2% pool fee, for the hours you set. It cuts the block subsidy in half at each halving, the next around Apr 2028, and otherwise assumes those carry on unchanged, which they won't. Income at today's difficulty and price is about 17% below that average. Hashrate usually rises, though miners that stop paying after a halving may switch off, which leaves more for the rest. How we work it out.
| Brand | 21energy |
|---|---|
| Model | Shield |
| SKU | H-21-SHD-XXXXXXX-N-X |
| Type | Space heater · Industrial |
| Form factor | — |
| Cooling | Air |
| Production status | Unknown * |
| Launch date | — |
| Hashrate | 24 TH/s |
| Power consumption (stock) | 2,000 W |
| Mining efficiency | 83 J/TH * |
| ASIC chip | Not known yet |
| Heat output | 6,824 BTU/h |
| Input voltage | 230 V, 16 A |
| Frequency | — |
| Net dimensions (W × D × H) | — |
| Net weight | — |
| Noise | 50–70 dB |
| Operating temperature | — |
| Area heated | 80 m² (maker's claim) |
| Colours | — |
| Company based in | Austria |
| Made in | Austria |
* Not confirmed by the maker's own documents yet.
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Not yet confirmed from the maker's own documents: form factor; dimensions; weight; operating temperature; production status; launch date; efficiency (computed: 2,000 W / 24 TH/s; the page's 'up to 75 J/TH' is a best-case claim).
Spotted a mistake? Let us know.