Calculating electricity costs for Bitcoin mining – simple formula & examples

Before you run a Bitcoin miner continuously, it is worth looking at the electricity bill – because power consumption is by far the largest ongoing cost of home mining. The good news: the calculation is very simple, and for a small Bitaxe we are talking about a few euros per month.

The formula

You only need two values: your device’s power draw in watts and your electricity price per kilowatt-hour (kWh). For 24/7 operation that is around 730 hours per month.

Monthly cost ≈ (watts ÷ 1000) × 730 × electricity price per kWh

Example: a Bitaxe at 15 watts and 30 ct/kWh → (15 ÷ 1000) × 730 × €0.30 ≈ €3.29 per month. Over a year, around €39.

Example values (at 30 ct/kWh)

• Bitaxe Gamma (~15 W): ~0.36 kWh/day → around €3.30 per month.
• Nerdaxe Gamma (~15 W): practically identical, around €3.30 per month.
• NerdQaxe ++ (~80 W): ~1.9 kWh/day → around €17.50 per month.
• NerdOctaxe (~200 W): ~4.8 kWh/day → around €44 per month.

If your electricity price is higher or lower, costs scale linearly: at 40 ct/kWh simply use the factor 40/30, at 25 ct/kWh use 25/30.

Don’t forget: the waste heat

A miner converts almost all the electricity it uses into heat. In winter it therefore heats along and replaces some heating output – this share you save again elsewhere. In summer the waste heat is more of a disadvantage, especially with the larger devices.

How to lower electricity costs

• Your own solar power: if you have a surplus during the day, you mine practically for free.
• Night or dynamic tariffs: use cheap time windows, pause during expensive ones.
• Efficiency tuning: with lower J/TH you get the same hashrate from fewer watts – see AxeOS tuning.
• Good cooling: cooler ASICs run more efficiently and stably.

Putting electricity costs in perspective

The electricity costs alone say nothing about whether mining “is worth it”. For that you have to weigh them against the expected return – and honestly, that is low with home mining. How to realistically add up both is shown in Calculating mining profitability realistically.

Bottom line: a small Bitaxe is a cheap hobby for the price of a coffee or two per month. With larger devices like the NerdOctaxe it is worth a close look at your electricity price – and the next logical step is our big guide to Bitcoin mining at home.