A solo miner successfully mined a Bitcoin block on Sunday, collecting a 3.137 BTC payout, worth about $371,000 at the time.

The miner operated through the Solo CK pool, a service for solo miners. They mined block 910,440 and collected the standard 3.125 BTC and about 0.012 BTC in transaction fees. The block included 4,913 transactions, and the fees totalled $1,455. 

With Bitcoin’s hashrate being dominated by massive industrial-scale mining operations, the chances of a solo miner hitting a block are slim. Yet, with efficient hardware, even smaller players can claim the same block rewards in rare instances. 

This year, several solo miners with smaller setups have claimed block rewards on their own. One successfully mined a block in February, while another netted $350,000 on July 4. On July 27, another solo miner was able to score a block alone, bagging $373,000 in rewards. 

Solo Bitcoin mining is still mostly a “lottery” 

Samuel Li, the chief technology officer of mining equipment company ASICKey, previously told Cointelegraph that solo Bitcoin miners are winning not because of luck but because of “powerful, efficient hardware.” 

Li said modern mining equipment is built to deliver serious hashrates without the power draw of traditional miners. However, this doesn’t mean the odds of solo miners winning have changed. 

“Solo mining is still mostly a lottery, unless you control tens of PH/s, which is realistically the bare minimum for having a measurable statistical shot at success within a reasonable time frame,” Li told Cointelegraph.

Li said that a miner with one petahash (PH/s) of hashpower has a 1 in 650,000 chance of solving a block every 10 minutes. 

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Rising network difficulty squeezes professional mining companies

Even established Bitcoin mining companies have felt the increasing network difficulty and hashrate, along with a reduced block subsidy due to Bitcoin halving. 

CryptoQuant data shows that at the time of writing, the difficulty of the Bitcoin network was at 129 trillion and was floating near all-time highs. The data also showed that network difficulty has only trended upward over time. 

Large mining companies have diversified into artificial intelligence and high-performance computing (HPC) to make up for the increased competition and shortfalls in the mining business. 

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