Utilities like Rayburn have to provide service to miners if it’s technically feasible to do so,

Besides threatening to boost power bills, the dozens of Bitcoin mines proposed are also a risk to the state’s shaky power grid after a deep freeze last year left hundreds dead and pushed up prices so much that utilities were left with massive debts or bankrupted.

Industry advocates argue that as Bitcoin mining booms in the state, someone will come along to build more power plants. One year after the deadly winter storm, a record amount of solar capacity is planned for Texas. Plus, miners say their ability to quickly throttle back operations when the grid needs power will actually make the system more stable.

Bitcoin mines shouldn't cost consumers much because they seek out more sparsely populated areas with electricity to spare, said Lee Bratcher, president of the Texas Blockchain Council, a lobbying group.

But Rayburn's experience shows that's not always the case. Miners are looking at remote sites, which in some cases will require millions of dollars in grid upgrades, Naylor said.

Austin Energy, which powers the state capital, says investors want to build five mines just outside Austin that would need a total of 1,000 megawatts of electricity, equal to about two-thirds of the city's current demand. That may require the utility to build more transmission lines,

Upgrades to the power system will be needed because the grid “can’t handle all of this new load,” said Evan Caron, a former power trader in Austin who invests in energy technology. New investments in the transmission system are typically shared among Ercot’s consumers and show up in their utility bills.

Given the crypto industry’s notorious volatility, there’s also the chance that miners will close up shop, leaving ratepayers to cover the costs of upgrades that may no longer be needed. To mitigate that risk, utilities can ask for a deposit, which would be refunded after the miner uses the power for a certain period of time.

The risks may pay off because crypto miners have pledged to shut down in times of crisis to conserve power, Naylor said. The biggest Bitcoin miner in Texas, Riot Blockchain, did so in February and last year, and others, such as Compute North LLC and Bitdeer Technologies Holding Co., have committed to shutting if needed.