Twice in the past few days, individual small miners have managed to validate a block by themselves and collect the 6.25 BTC reward.
How Bitcoin mining works
Currently, the total current computing power allocated to Bitcoin mining worldwide is just under 200 Ehash/s.
Typically the percentage of blocks mined by any single miner is the percentage it holds of the total hashrate, so for a single miner to secure say 10% of the mined blocks it needs to have around 20 Ehash/s.
Since it is impossible for a single small miner to reach these figures, there are usually only two possibilities:
- share your small computing power with other miners by participating in a pool,
- invest huge sums to build a mega mining farm.
The miner validating a Bitcoin block on his own
A few days ago, however, a single miner with only 126 Thash/s, or 0.000126 Ehash/s, managed to single-handedly mine a block and collect the 6.25 BTC prize.
This was revealed by Con Kolivas, administrator of the solo.ckpool.org pool, by linking to the 718.124 block tab on an explorer that shows Solo CK as the block miner.
— Dr. Con Kolivas (@ckpooldev) January 11, 2022
Previously it appears that the same thing had happened on December 2, 2021 with block 712.217.
What is really very surprising is that 126 Thash/s is only 0.000073% of the total Bitcoin hashrate, so statistically that single miner should have been able to mine one in every 1.3 million blocks. Instead he succeeded even though the total number of blocks mined on Bitcoin over 13 years is only slightly more than half that.
Furthermore, only just over 52,000 blocks are typically mined on the Bitcoin blockchain in a single year, so the odds of succeeding with 0.000073% of the hashrate are slim.
The miner will now have to pay the pool a 2% fee, but will be able to keep the remaining 6.125 BTC, which is about $260,000.
It is not known how much he spent on electricity, or how much he had to invest in order to get 126 Thash/s, but a state-of-the-art 140 Thash/s ASIC costs about $11,000. So it seems quite likely that the miner made a lot of money from this operation.