Calculate Bitcoin Mining ROI: A Guide
"Is Bitcoin mining still worthwhile?" – I hear this question daily. The honest answer: it depends. Not on the Bitcoin price, but on your individual situation. Here's how to calculate it yourself.
The Four Factors of Profitability
1. Electricity Costs (most important factor)
Electricity makes up 80-90% of operating costs. The difference between €0.05/kWh and €0.30/kWh determines profit or loss.
2. Hardware Efficiency
Measured in joules per terahash (J/TH). Current top miners are at 20-25 J/TH. Older models at 30-50 J/TH. More efficient = lower electricity costs per mined bitcoin.
3. Heat Utilization
The game-changer for small operators. If you use the waste heat (heating, hot water), count these savings against electricity costs.
4. Bitcoin Price & Network Difficulty
Both fluctuate, but both increase long-term. For calculations, use conservative assumptions.
The Basic Formula
(Hashrate in TH/s × 86,400 seconds × Block Reward) / Network Difficulty
Simplified: Use a mining calculator like whattomine.com
Example Calculation: Antminer S19 Pro
Assumptions:
- Hashrate: 110 TH/s
- Consumption: 3,250 W
- Electricity price: €0.10/kWh
- Bitcoin price: €80,000
Calculation:
- Daily electricity consumption: 3.25 kW × 24h = 78 kWh
- Daily electricity cost: 78 × €0.10 = €7.80
- Daily mining revenue: ~0.00012 BTC = €9.60
- Daily profit: €9.60 - €7.80 = €1.80
- Monthly profit: ~€54
With Heat Utilization
The same miner produces ~3 kW of heat. If you use it for heating:
- Heating cost savings: ~3 kW × 24h × €0.10 = €7.20/day
- Effective profit: €1.80 + €7.20 = €9.00/day
- Monthly profit: ~€270
Heat utilization increases profit fivefold!
When Is It Worthwhile?
• Under €0.05/kWh → Highly profitable (e.g., surplus electricity)
• €0.05-0.10/kWh → Profitable, better with heat utilization
• €0.10-0.15/kWh → Borderline, only with heat utilization
• Over €0.15/kWh → Only worthwhile with free electricity
Hardware Break-Even
A new miner costs €2,000-4,000. At €54/month profit, it takes 3-6 years to break even. With heat utilization (€270/month) only 8-15 months.
This is why heat utilization is so important: It dramatically shortens the amortization period.
Free Electricity = Maximum Profit
Those with surplus electricity (PV curtailment, biogas surplus) effectively pay €0/kWh. Then mining is extremely profitable:
- No electricity cost deduction
- Full mining revenue as profit
- Plus heat utilization as bonus
Conclusion
Bitcoin mining profitability isn't a yes/no question. It depends on your electricity costs and heat utilization. The right question isn't "is mining worthwhile" but "how cheap is my electricity and can I use the heat?"
Individual Profitability Analysis?
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