Mine bitcoin or buy it?
The question everyone asks when they see the power price: is a home miner worth it, or is it better to just buy bitcoin? At Brazilian retail rates, buying almost always wins. The math compares the cost of mining vs buying — at your tariff, rig, and scale.
Verdict
Buy. Home mining does not pay here.
At R$ 0,85/kWh, with 1× Antminer S21 Pro, producing bitcoin loses to simply buying. The best alternative to buying (Rent hashrate (HaaS)) would return −US$ 380/year vs DCA — and still require a power bill of R$ 2.148/month, 13× a typical home.
Where you mine
residential B1, all-in with taxes (ANEEL)
Which rig
234 TH/s · 3.51 kW · 15.0 J/TH · ~US$4.000 (new · air)
capex ~US$4.000 · 1 rig (home minimum)
Cost to produce 1 BTC
US$ 145.808
R$ 787k · energy + capex
2,3× the market price
Buy on the market
US$ 63.374
R$ 342k · just buy it
HashrateIndex, average of Jun/2026
Energy break-even
R$ 0,24
24.0 R$-cents (≈4.5 US¢)/kWh
mining only wins below this
Power bill / month
R$ 2.148
2.527 kWh · breaker ~20 A
13× a typical home (~200 kWh)
Buy vs mine vs rent — year-1 result, same money (capex of 1× Antminer S21 Pro = ~US$4.000)
| Strategy | Sats in year 1 | Net in year 1 | |
|---|---|---|---|
| Buy (DCA)spread+fees −1,0% once | 6.248.619 | −US$ 40−R$ 216 | |
| Self-mine1× rig · does NOT run at this tariff (only loses idle capex) | 0 | −US$ 1.333−R$ 7.200 | |
| Rent hashrate (HaaS)premium +10,6% + buy friction | 5.649.746 | −US$ 420−R$ 2.265 |
Mining only beats buying below R$ 0,24/kWh for the Antminer S21 Pro (24.0 R$-cents (≈4.5 US¢)) · renting (HaaS) at +10,6%: never beats buying. Rational operation: at a fixed tariff the rig runs all year or stays off (loss limited to idle capex).
Why buying almost always wins
The bill mining videos hide is electricity. At Brazilian residential retail (~R$ 0,85/kWh, all-in with taxes — ANEEL), the energy to produce 1 bitcoin costs more than twice buying one ready-made. The "naive" miner running 24/7 on the home tariff loses money — the same finding as the mwhash benchmark: the naive heat-miner loses. Grid fees are the moat between hobby and industry.
Mining only beats buying below the energy break-even shown above — curtailed, stranded, or behind-the-meter territory, where the kWh costs cents. Renting hashrate (HaaS) never beats buying: the marketplace premium is the seller's margin — measured at +10,6% on the NiceHash order book (2026-07-04). And BTC appreciation does not change the verdict: it benefits mining and buying equally, because both strategies end holding bitcoin.
Full method, data and versioned assumptions at methodology and sources — frontier.py, break-even, HaaS premium. Argue with the parameters, not vibes. Not financial advice.
Frequently asked questions
- At what electricity rate is home bitcoin mining profitable?
- Mining beats buying below R$ 0.24/kWh in the default scenario. This break-even is computed for an Antminer S21 Pro, a bitcoin price of US$ 63,374, and a 933 EH/s network.
- Is it cheaper to mine bitcoin or buy it directly in Brazil?
- Buying directly is cheaper at the default residential rate of R$ 0.85/kWh. Producing 1 BTC with the Antminer S21 Pro costs US$ 145,808 all-in, or 2.3× the US$ 63,374 bitcoin price used in the calculation.
- How much does one bitcoin miner add to a monthly electricity bill?
- One Antminer S21 Pro adds about R$ 2,148 per month at the default residential rate of R$ 0.85/kWh. The machine consumes 2,527 kWh per month when running around the clock.
- Is renting hashrate cheaper than buying bitcoin?
- No: rented hashrate costs 10.6% more in the measured scenario, before buy friction. The premium comes from the NiceHash order book and feeds the same calculation comparing HaaS, self-mining, and a direct purchase.