Hashrate Heating: Running a Bitaxe Through an Aussie Winter

Every winter, every Aussie in a pre-war weatherboard in Melbourne or a brick-veneer walk-up in Canberra runs a 2 kW panel heater for 14 hours a day and watches the power bill walk past AU$400.

The marginal cost of that heat is currently 35 cents per kilowatt-hour. You’re paying 70 cents an hour to warm one room.

What if those same watts also mined sats?

This is the “hashrate heating” pitch. It’s been a cult corner of the bitcoin mining world since ~2019. In 2026, with Bitaxe and NerdQaxe hardware at hobby-friendly prices and Australian electricity tariffs where they are, the maths has shifted from “nice meme” to “actually worth considering.”

How hashrate heating works

All electric resistive heating is 100% efficient at the power-to-heat conversion: every watt you put in becomes roughly one watt of heat. Panel heater, oil column, fan heater — they’re all the same physics, differing only in form factor.

A bitcoin ASIC is also, from the thermodynamic perspective, a 100%-efficient electric heater. The only difference is that while converting the electricity to heat, it also performs useful computation that has a market value denominated in satoshis.

So a Bitaxe on your desk is:

• A 17 W space heater (negligible for heating, but fine for warming your hands)
• A sats generator producing ~AU$24/year at current difficulty and AU$100k BTC

A rack of 20 NerdQaxe++ units is:

• A 1500 W space heater (equivalent to a small panel heater)
• A sats generator producing ~AU$2000/year

The second scenario is real and has been deployed by Aussie bitcoiners in Victoria and Tasmania. A single NerdQaxe++ is loud in a bedroom but perfectly acceptable in a garage, shed, or dedicated utility room.

The honest cost comparison

Let’s say you currently heat your living room with a 2000 W panel heater 4 hours per day in winter (Melbourne June–August, ~90 days):

Panel heater scenario:

• Power: 2000 W × 4 h × 90 d = 720 kWh
• Cost at $0.32/kWh peak: AU$230
• Heat delivered: ~720 kWh
• Sats earned: $0

Hashrate heater scenario (26 NerdQaxe++):

• Power: 1950 W × 4 h × 90 d = 702 kWh
• Cost at $0.32/kWh peak: AU$225
• Heat delivered: ~702 kWh (same)
• Mining revenue at current difficulty: ~AU$190 over the 90-day window
• Net cost: AU$35

You paid AU$35 to heat your house for three months. The panel heater cost AU$230 for the same warmth.

That’s the pitch.

The elephant: heat pumps

The above comparison is rigged because it assumes resistive heating. An air-sourced heat pump (reverse-cycle AC) is 3–4× more thermally efficient than resistive because it moves heat rather than generating it.

Heat pump scenario:

• Power: 600 W × 4 h × 90 d = 216 kWh (COP of ~3.3)
• Cost at $0.32/kWh peak: AU$69
• Heat delivered: ~720 kWh (equivalent)
• Sats earned: $0

If you already have reverse-cycle AC (which most modern Aussie homes do), hashrate heating loses the comparison on cost efficiency unless you’re mining on very cheap power.

So the clean version of the argument:

• If you currently use resistive electric heating: hashrate heating is an unambiguous win. Replace the panel heater with a mining rack. You save money and stack sats.
• If you currently use gas or reverse-cycle AC: hashrate heating is a political choice, not an economic one. You’re choosing to spend more on heating in exchange for sats.
• If you have rooftop solar: the calculation flips again — see our mining economics article for the solar maths.

The Tasmanian sweet spot

Tasmania is the best place in Australia to do this. Three reasons:

1. Cold climate: you genuinely need 5–6 months of heating per year.
2. Cheap hydro: Tasmanian off-peak controlled-load tariffs hit AU$0.14/kWh, and the standing tariff is around $0.28 — well below mainland peak.
3. Low grid carbon intensity: Tasmanian hydro is ~95% renewable, so your mining/heating is also low-emission.

An Aussie bitcoiner in Launceston running 20 NerdQaxe++ units in a utility room from April through October would offset most of their heating bill with mining revenue AND reduce their carbon footprint vs gas.

The practical setup

If this sounds like you, the practical setup looks like:

1. Utility room, garage, or cupboard with passive or exhausted airflow into the living space.
2. Dedicated circuit — a 10A standard socket can run 4–5 NerdQaxes or 20+ Bitaxes. A 15A circuit doubles that.
3. Smart plug or PDU for remote control — you want to turn the rack off if the pool goes down or the room overheats.
4. Ducting to push the hot air where you want it — flexible HVAC ducting from a hardware store is fine.
5. Acoustic treatment if near living areas — fan noise is the biggest complaint.
6. Smoke detector nearby — mandatory, not optional.

The philosophical version

There’s a broader idea called “Heatpunks” — the notion that miners are a load-balancing mechanism for the grid. They soak up excess solar in summer and excess hydro in winter, turning bitcoin into a physical battery for otherwise-curtailed electricity.

You don’t have to buy the philosophy. But if you’re in Hobart or Ballarat in July and you’re already paying AU$0.32 to warm your lounge room, the economic case is clearer than people realise.

Stack sats. Heat the house. Same watts.

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Numbers assume current network difficulty and AU$100k BTC. Your mileage will vary. Power prices change; difficulty adjusts; BTC price does what BTC price does. Follow the RSS for quarterly updates.

Frequently Asked Questions

How much heat does a Bitaxe actually produce? +

A Bitaxe Gamma dissipates ~17 W as heat. A NerdQaxe++ dissipates ~75 W. For context, a small standing electric heater is 1500–2400 W. A single Bitaxe won't warm a room, but 20 of them will — and 20 Bitaxes dissipating 340 W mine ~0.0013 BTC/year, roughly AU$135.

Is this cheaper than a regular heater? +

No. It's the same cost in watts. The trick is that the watts ALSO produce sats. So a mining heater is an electric heater you get paid to run. The question is whether the sats you earn exceed the efficiency gap between a resistive heater and an air-sourced heat pump (which move 3x the heat per watt).

What's the downside? +

Noise, mostly. A Bitaxe Gamma's fan is 25–35 dB — fine. A NerdQaxe++ is ~50 dB, which is noticeable in a bedroom. A rack of 20 Bitaxes is tolerable under a desk, uncomfortable in a living room. Cooling airflow matters.