But Bitcoin remains so hard to use that a major Bitcoin conference in January had to stop accepting Bitcoin. It is, in practice, a speculative investment, like gold. And Tyler Cowen, an economist at George Mason University, said mining gold was a better use of resources, because even if it lost value, it could be used to fill teeth.

“Once the Bitcoin power is burned, it is never coming back,” he said.

Colin L. Read, the mayor of Plattsburgh, N.Y., also sees it as a public nuisance. The city was guaranteed a fixed supply of cheap electricity as part of the construction of power-generating dams on the St. Lawrence in the 1950s. Bitcoin mining companies are plugging into that power supply like a swarm of hungry mosquitoes.

Mr. Read said that Bitcoin mining now consumes about 10 percent of the city’s power, and that is forcing Plattsburgh to buy a growing amount of extra electricity on the open market, at rates up to 100 times higher than its base cost.

Mr. Read, who is also an economics professor, said he would rather sell the city’s supply of cheap power to companies employing large numbers of people. Mold-Rite Plastics, which makes bottle caps, also uses about 10 percent of the city’s power, but it employs about 200 people. The mining companies? “They hire a security guard,” he said. “And a guy who comes when something breaks.”

David Bowman, who describes himself as Plattsburgh’s first Bitcoin miner — “I started a long time ago, around 2014,” he said — started with a handful of computers. Now he has 20 machines.