21energy Ofen 3 Base XL
- Hashrate
- 80 TH/s
- Power
- 2,000 W
- Efficiency
- 25 J/TH
- Noise
- 40 dB
Space heater Floor standing Pre-order
The top Ofen 3: a 2.2 kW heater for rooms up to 110 m² with up to 120 TH/s at a quoted 17.5 J/TH, the most hashrate in 21energy's home range. Large 63 x 83 cm housing, about 40 dB, app control. Deliveries announced from November 2026; the shop shows January 2027.
Best price $3,700
$30.83 per TH · New · Pre-order at 21energy · excl. tax
delivery window shown Jan 4-19
| Store | Trustpilot | Condition | Availability | Listed price | In your currency | Per TH | Checked | Link |
|---|---|---|---|---|---|---|---|---|
| 21energy Ships from Austria · Maker's own shop delivery window shown Jan 4-19 | TrustScore 4.8 out of 5, 1,194 reviews | New | Pre-order | €3,325 excl. tax | $3,700 | $30.83 | 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 | Ofen 3 Pro XL |
| SKU | H-21-O3X-XXXW120-N-X (white) / H-21-O3X-XXXB120-N-X (black) |
| Type | Space heater · Home |
| Form factor | Floor standing |
| Cooling | Air |
| Production status | Pre-order |
| Launch date | — |
| Hashrate | 120 TH/s |
| Power consumption (stock) | 2,200 W |
| Mining efficiency | 17.5 J/TH |
| ASIC chip | Not known yet |
| Heat output | 7,507 BTU/h |
| Input voltage | — |
| Frequency | — |
| Net dimensions (W × D × H) | 630 × 160 × 830 mm (24.8 × 6.3 × 32.7 in) * |
| Net weight | — |
| Noise | 40 dB * |
| Operating temperature | — |
| Area heated | 110 m² (maker's claim) |
| Colours | White, Black |
| Company based in | Austria |
| Made in | Austria |
* Not confirmed by the maker's own documents yet.
WhiteBlack
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Not yet confirmed from the maker's own documents: weight; input voltage; frequency; operating temperature; heat modes; dimensions orientation; minimum noise; launch date (deliveries announced from Nov 2026; not yet confirmed shipped).
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