Bitcoin heater: warm a room with a home miner

That is what a Bitcoin heater or mining heater is: a miner used as a small space heater that runs around the clock. It brings warmth to a desk, a study or a bedroom, but it does not replace the heating of a whole home. For scale, a common fan heater draws 1,000 to 2,000 W; the miners on this page draw 70 to 220 W and give off that heat steadily, day and night. Below you will find how much heat and noise each of them makes, what a month of warmth costs, which miner suits which room, where to put it and what to do with it in summer.

How much heat each miner gives off

For heat, one number counts: the power draw. A miner gives off all the electricity it takes from the socket as warmth, whether it finds a block or not, so its power draw is its heat output. The table lists that value together with noise, hashrate and cooling as our catalogue gives them, sorted by heat output. Where the catalogue has no value, the table says so; we do not estimate.

Efficiency does not change the heat. The Avalon Nano 3s and the NerdQX both give off 140 W; the NerdQX turns them into 8 TH/s, the Avalon into 6 TH/s. Efficiency decides how much hashrate you get for the same warmth, not how warm the room gets.

Two of these models carry a measured noise level: the Avalon Nano 3s with 33 dB in quiet mode and 38 dB in normal mode, and the NerdQX with 38 dB. The two Hydro models carry the heat of their chips through a closed water loop to a radiator, where a large fan pushes it out slowly; their data sheets give no dB figure, and neither does the one of the NerdQAxe++.

What a month of warmth costs

The only running cost is electricity. Watts times 720 hours a month, divided by 1,000, gives the kilowatt hours; multiply them by your tariff. The table uses 0.30 EUR per kWh as an example; your own price is on your electricity bill.

Per kilowatt hour, the warmth of a miner costs the same as the warmth of an electric heater on the same tariff, because both turn all of their electricity into heat. The difference is what else you get: the heater gives you warmth, the miner gives you the same warmth and computes Bitcoin hashes with it. If you heat with something that costs you less per kilowatt hour of warmth, the warmth of the miner is the more expensive one.

Which miner for which room

• Bedroom or living room, where quiet counts: the Avalon Nano 3s. Its quiet mode at 33 dB is the lowest measured value on this page, and its closed housing has no exposed board and nothing to assemble; you set it up with the manufacturer app on your phone. It gives off 140 W of heat, as much as the NerdQX, with 6 TH/s instead of 8 TH/s.
• Study or home office: the NerdQX. The same 140 W of heat as the Avalon, but 8 TH/s from four BM1370 chips under a tower heatsink with a 120 mm fan at the front and a 90 mm fan at the back. At 38 dB you will hear it in a silent bedroom but not in an office, and its colour display shows hashrate, temperature and power at a glance.
• A warm corner at your desk: the NerdQAxe++. With 70 W it gives off half the heat of the Avalon or the NerdQX and still reaches 4.8 TH/s from four BM1370 chips; at about 15 J/TH it is the most efficient miner on this page. It is an air-cooled board, so give it a spot where air can move around it.
• More heat without a small, fast fan: the Hydro models. The NerdQAxe++ Hydro (100 W, 6 TH/s) and the NerdOctaxe Hydro (220 W, 14 TH/s) carry the heat through a closed water loop to a radiator, where a large fan moves it into the room slowly. The NerdOctaxe Hydro is the biggest heat source on this page; in a small room you will notice it.

Current prices and availability are on the product cards below.

Where to put it

• Free air around it. Stand the miner on a desk, a shelf or the floor where air can reach it. Do not cover it and do not put it in a closed cupboard or a drawer: the heat stays inside instead of warming the room, and the NerdQX, for example, reduces its clock when it gets too warm.
• The warm side towards the room. The NerdQX draws air in at the front and blows it out at the back; the Hydro models push the warm air out through their radiator. Keep that side clear and let it face the room, not a wall or a curtain.
• The power supply from the box. The Avalon Nano 3s comes with its USB-C power supply (28 V / 5 A), the NerdQX with its power supply, the NerdQAxe++ Hydro with a 12 V / 10 A unit and the NerdOctaxe Hydro with a 12 V / 20 A unit. Use that one, plugged into an ordinary wall socket.
• Within reach of your Wi-Fi. All five connect to a 2.4 GHz Wi-Fi network, the Avalon through the Wi-Fi module in its box. Setup takes minutes: the Avalon in the app, the others in AxeOS in your browser, with every step in the NerdQAxe++ setup guide.

In summer

A miner does not know the seasons: 140 W are 140 W of heat in July as well. When the warmth is no longer welcome, you have these options:

• Quiet mode on the Avalon Nano 3s. It trades output for quiet: 33 dB instead of 38 dB in normal mode.
• A lower frequency on the AxeOS miners. On the NerdQX, the NerdQAxe++ and both Hydro models, frequency is a field in AxeOS in your browser. A lower operating point means less hashrate and less power, and so less heat: the NerdQAxe++ runs its four BM1370 chips at 70 W, the NerdQX runs the same four chips at a higher operating point and draws 140 W.
• A smaller miner or none. Let a smaller miner take over in the warm months, or switch the miner off and back on when it gets cold. While it is off, it neither heats nor mines.

Your chance at a block

While it heats, a miner computes real Bitcoin hashes. Pointed at a solo pool, each of them is a ticket for a full block reward, currently 3.125 BTC plus the transaction fees of that block, paid to a Bitcoin address that belongs to you, minus the fee of the pool if it charges one; more hashrate means more tickets per round. For a single home miner the odds are small, and they change with the hashrate of the whole network every day, so we do not print a number here. How to work out your own chance is in the solo Bitcoin mining guide, and our page on Bitcoin lottery miners compares the lottery and solo miners we stock by hashrate and power draw.