Miner

What miners do

A typical Bitcoin miner:

1. Receives pending transactions from the mempool.
2. Bundles them into a candidate block.
3. Computes hashes repeatedly, adjusting a nonce each time, trying to find a hash below the difficulty target.
4. If they find a valid hash before others, they broadcast the block.
5. Other nodes verify and accept the block.
6. The miner receives the block reward (newly issued BTC plus transaction fees).

This is the proof-of-work mining loop.

Hardware evolution

Bitcoin mining hardware has evolved dramatically:

• 2009-2010 — CPU mining. Anyone with a computer could mine.
• 2010-2012 — GPU mining became dominant; specialized graphics cards.
• 2013- — ASICs (Application-Specific Integrated Circuits) — purpose-built mining hardware that dominates SHA-256 mining.
• Modern ASICs (2024-2025) — produce 200+ TH/s at very low power-per-hash.

Each generation has obsoleted prior hardware. Competing today requires the latest ASICs and cheap electricity.

Mining economics

A few drivers:

• Bitcoin price. Higher price = higher revenue per block.
• Hash rate. Higher network hash rate = lower share of rewards per unit of computing power.
• Electricity cost. Operating expense; varies enormously by location.
• Hardware efficiency. Newer hardware uses less electricity per hash.
• Mining difficulty. Adjusts to keep block time near 10 minutes regardless of network hash rate.

The combination determines profitability. Marginal miners shut down when prices fall; new miners enter when prices rise.

Mining at scale

Industrial-scale miners dominate Bitcoin mining today:

• Major operators — Marathon Digital, Riot Platforms, Core Scientific, CleanSpark, Hut 8, others. Public companies operating large facilities.
• Locations — North America (largest share), Russia, Kazakhstan, smaller pockets globally. Geographic distribution shifted after China's mining ban in 2021.
• Operations — large data centers; specialized cooling; substantial electricity contracts.

Individual home miners largely can't compete on Bitcoin; the economics favor large-scale operators.

Mining pools

Most miners join mining pools rather than mining solo:

• Pool combines hash power from many miners.
• Pool finds blocks more frequently than individual members would.
• Rewards are distributed proportionally to contributed hash power.
• Smooths income for individual miners who could rarely find blocks solo.

Major pools (Foundry USA, AntPool, F2Pool, ViaBTC, Binance Pool) collectively control most Bitcoin hash rate.

Halvings and miner stress

Halvings cut block rewards in half every ~4 years:

• Immediate effect: miner revenue drops by half overnight.
• Less-efficient miners become unprofitable and shut down.
• Industry consolidation accelerates.
• Hash rate sometimes drops temporarily before difficulty adjustment compensates.

Each halving has produced significant industry restructuring. The 2024 halving was followed by the usual stress and consolidation patterns, against the backdrop of Bitcoin ETF inflows providing some price support.

Beyond Bitcoin

Other proof-of-work chains have miners:

• Litecoin — Scrypt mining; less ASIC-dominated than Bitcoin.
• Bitcoin Cash, Bitcoin SV — share Bitcoin's SHA-256 mining ecosystem.
• Dogecoin — merge-mined with Litecoin.
• Various small PoW chains — vulnerable to attacks because of low hash rate.

Most major chains have moved away from proof-of-work to proof-of-stake, but Bitcoin and a few others remain PoW.

Ethereum's transition away from mining

Ethereum mining ended in September 2022 with the Merge, which moved Ethereum to proof-of-stake. The transition:

• Ended Ethereum mining overnight.
• Many miners migrated to Bitcoin (where they could) or to small alternative PoW chains.
• GPU mining largely ended as a category, since Ethereum was the dominant GPU-mineable chain.

The transition was a major event in mining industry history. Subsequent attempts to maintain Ethereum proof-of-work (EthereumPoW) have minimal economic activity.

Environmental concerns

Bitcoin mining's energy use is contentious:

• Total electricity consumption at the level of a small country.
• Estimates of clean-energy share vary widely (industry estimates higher; critics lower).
• Specific use cases — flared gas, stranded renewables, grid balancing — represent positive environmental contributions for some operators.
• Critics argue any energy used on Bitcoin is "wasted" given alternative uses.

The honest assessment: Bitcoin mining uses meaningful energy; the appropriate question is whether the security guarantee is worth the cost. Reasonable people disagree about whether the answer is yes.

Public-company mining

Several public companies are dedicated Bitcoin miners:

• Marathon Digital, Riot Platforms, Core Scientific, CleanSpark, Hut 8.
• Stocks sometimes track Bitcoin price but with leverage (mining economics amplify).
• Operating cycles — periods of profitability followed by stress as price falls or halvings cut rewards.
• Different strategies — some hold Bitcoin treasuries; some sell production to fund operations.

These companies provide indirect Bitcoin exposure with significant operational and financial complexity.

What individuals should know

For most retail crypto holders:

• Solo Bitcoin mining is impractical. Industrial economics dominate.
• Mining stocks provide leveraged exposure but with operational and financial complexity.
• Home mining can make sense for small alternative PoW chains, hobbyist purposes, or where electricity is essentially free.

For investors:

• Mining stocks behave like leveraged Bitcoin exposure plus operational specifics.
• Halving cycles matter for industry economics.
• Hash price (revenue per unit of hash) is the standard miner-economics metric.

The mining industry is a central piece of Bitcoin's infrastructure. Its evolution from individual hobbyists to industrial-scale operations reflects Bitcoin's growth from experiment to global asset.