Usually the gas is burned off at the well. Environmentalists say using it for mining incentivizes more drilling.

The city of Rockdale hopes cryptocurrency miners can make up for lost industrial jobs and tax revenue.

The miners have blown through one town’s allocation of cheap power, while another has put a moratorium on new mining operations.

Over the past decade, digital currencies (particularly bitcoin) have exploded in popularity.

Ingredients: Tens of thousands of powerful computers, enough energy to power all of Poland. Yield: More than $30 million in newly minted bitcoin every day.