US Bitcoin Mining Explained: Who Mines, What Power Costs and Why Texas Pays Miners to Switch Off

1. Bitcoin mining

What is mining?

To put it simply, thousands of computers on the Bitcoin network race to add the next block to the blockchain, the shared public record of all Bitcoin transactions. The winner gets newly issued bitcoin plus the transaction fees. It works like a lottery where more guesses mean more tickets: the first computer to find the right answer to a cryptographic puzzle wins. A new block arrives about every 10 minutes, and the difficulty of the puzzle adjusts every two weeks to hold that pace. The reward for each block is currently 3.125 BTC.

Figure 1: From electricity to bitcoin reward.

Why is mining so energy intensive?

The guessing is done by special-purpose machines called ASICs (Application-Specific Integrated Circuits), built for this one task only. Each guess costs energy, and the whole security of Bitcoin rests on the fact that guessing is expensive. This is why miners set up shop where electricity is cheapest, and why power cost decides who survives when prices fall.

2. The United States in the global picture

China banned crypto mining in 2021. Before the ban, the country hosted most of the Bitcoin network. After it, miners moved abroad, and the United States became the largest host.

Figure 2: US share of global hashrate, three estimates.

Table 1: Estimates of US share of global hashrate.

Cambridge surveyed 49 firms (48% of the network) and warned that its US figure is probably overstated. A share of a third to two-fifths of global hashrate is a fair estimate. Texas is the centre of US mining because its ERCOT power market is deregulated (see Section 7), while Kentucky, Georgia, New York and Wyoming also host significant capacity.

3. The main US mining companies

Periods differ by company, so read Table 2 as a snapshot and not a ranking.

Table 2: Company snapshot. Market caps from Yahoo Finance, 22–28 September 2026.

4. How much do they mine?

Figure 3: Average BTC produced per day. Periods differ.

Figure 4: Company hashrate (energized, operational or deployed).

The whole network issues about 450 BTC a day, so MARA’s 26.6 BTC a day is roughly 6% of all new bitcoin. That lines up with MARA Pool’s 5.27% share of blocks on Hashrate Index.

An interesting pattern is that some miners sell more BTC than they produce. Riot sold 3,778 BTC against 1,473 produced. Core Scientific sold more than 2,000 BTC across the first half of the year. In contrast, MARA bought none in Q2 but kept most of its stack, and CleanSpark has held much of its output.

5. Power: where it comes from and what it costs

Where does the electricity come from?

Most US miners buy power from the grid or sign long-term contracts with power producers. They don’t usually build their own power plants, although MARA’s wind farm and its Long Ridge deal are moves toward owning supply. Three patterns stand out.

•             Cheap grid power in Texas. ERCOT wholesale prices let miners buy power at about 4 to 6 cents per kWh, and Texas offers tax abatements.

•             Selling flexibility. Riot earned $21 million in power credits in Q1 2026, up 171% from a year earlier, mostly for switching off during grid stress. Those credits pulled its all-in power cost down 21% to 3.0 cents.

•             Wind, solar and stranded gas. Miners use surplus renewable power and natural gas that would otherwise be flared off. Texas has some of the cheapest utility-scale solar in the country, at about 2.8 cents per kWh.

Globally, the Cambridge survey puts mining’s sustainable energy share at 52.4% (April 2025). US miners vary widely, from ERCOT (grid power, part wind and solar) to Kentucky (grid power, heavily coal-based). A US-specific number is worth checking against primary data before this report is used in a formal submission.

What does it cost?

Figure 5: Power cost per kWh. Riot’s is net of credits.

As difficulty climbed, MARA’s energy cost per bitcoin rose to $38,690, while CleanSpark improved to 5.2 cents per kWh from 5.6. One estimate puts the industry’s cost at about $74,300 per bitcoin (January 2026).

A worked example: one machine, one day

An Antminer S23 XP Hyd (600 TH/s, 5,340 watts) earns $23.84 a day. Each cent of power price is worth about $1.28 a day per machine, or nearly $47 million a year across 100,000 machines.

Figure 6: One machine’s daily economics at three power prices. Author’s calculation.

6. Public miners: production and treasury

A capital.com ranking puts the three pure-play miners on one footing (Table 3).

Table 3: Production and treasury. Source: capital.com ranking.

Together they mine about 57.4 BTC a day, roughly 12.8% of the 450 BTC issued daily, and hold 64,960 BTC. MARA’s treasury is more than the other two combined and equals about 4.4 years of its output, against 2.6 years for Riot and 2.0 years for CleanSpark. Output per EH/s is 0.31 BTC a day for MARA, 0.38 for CleanSpark and 0.39 for Riot, though fleet size and output cover different dates.

These figures differ from Table 2 because of reporting dates (MARA 2,422 BTC, CleanSpark 614 BTC and a 13,924 BTC treasury there). Company filings take priority.

Where the Texas capacity sits

Riot and Bitdeer share the former Alcoa aluminum plant site at Rockdale. Together, the four operators below span six Texas locations.

Table 4: Major Texas operations. Source: capital.com.

7. The Texas model: miners as flexible load

ERCOT, the Texas grid market, is the main test bed for miners as flexible load.

Table 5: Texas flexible-load figures.

Texas mining demand is projected to grow about 24% by 2027. If it sits inside the 9,500 MW category (not confirmed), it makes up about 45% of it. Running 4,288 MW all year would use roughly 37.6 billion kWh, but that is a ceiling, since miners switch off when the grid is tightest.

How demand response works

Miners contract with grid operators or join ancillary-services markets. When prices spike during extreme heat or cold, they cut or halt operations. They earn by selling their contracted power back at spot prices and from demand response payments. In surplus periods, they ramp up and absorb power that might otherwise be wasted.

Riot Platforms as a case study

Riot’s Q3 2025 credits of $30.6 million, up 147%, imply about $12.4 million a year earlier and work out to roughly $333,000 a day. November’s $2.3 million, 57% of it from demand response, averaged about $77,000 a day; summer price peaks probably explain the gap. If all the Q3 credits came from Rockdale, that is about $43,700 per MW, an upper bound since Riot also runs Corsicana.

Who benefits

Renewable generators gain a buyer of last resort, grid operators gain load they can switch off, and miners get cheaper power in exchange for interruptible supply. Cambridge CCAF found this benefit strongest in markets with high renewable penetration.

Why this matters: Texas miners earn income from the grid as well as from bitcoin. Caution: the credit data covers Riot only, income swings with price spikes, and the 9,500 MW figure includes AI data centres.

8. Mining pools and Foundry USA

What is a mining pool?

A pool combines many miners’ computing power and shares each reward according to how much each one contributed. Members get steady small payments instead of rare large ones. Under the FPPS payout method, a pool pays the expected block reward plus fees whether or not it finds a block. A pool does not own the mining machines, and a pool’s share of hashrate does not tell you where the miners are located.

What is Foundry USA?

The world’s largest mining pool is run by Foundry, which was formed in 2019 as a subsidiary of Digital Currency Group. Foundry is based in Rochester, New York, and is led by CEO Mike Colyer, formerly of Core Scientific.

Figure 7: Foundry USA timeline. The Fortitude Mining date is approximate.

Why Foundry matters

•             An American institution. It was built to bring legitimacy and North American capital to a sector dominated by China.

•             Serves institutions. Listed miners need auditable payouts.

•             Brought machines to the US. Bitmain credits Foundry’s activity for its shipments into the US.

•             Concentrates influence. Controlling a quarter or more of blocks is a risk, though members can switch pools and the share is far below 51%.

Figure 8: Pool share of network hashrate. US-based pools in orange. Source: Hashrate Index.

Table 6: Top pools on Hashrate Index.

Foundry, MARA Pool, and Luxor together hold about 33% of network hashrate, similar to estimates of the US share of mining, though the two measures differ.

Sources: Hashrate Index, Yahoo Finance, MARA, Riot and CleanSpark 2026 filings, Core Scientific Q2 coverage, Foundry, Fortune, The Block, Spark.money, Cambridge CCAF (Q1 2026), capital.com, Cointelegraph, CoinGeek, and Forklog.