A once-dormant power plant buzzes with activity outside Pittsburgh as thousands of miners work around the clock.
The miners on this site are not people, but supercomputers running complex mathematical equations. The first to solve the equation is rewarded with the digital financial token known as bitcoin.
But the vast amount of energy needed to run these computers has reignited a debate in Pennsylvania and across the country about the potential climate consequences of cryptocurrency.
Bitcoin is a type of digital currency that is not regulated by any company or government. It can be exchanged online between people anywhere in the world without going through a bank. While coins like quarters or cents are physically minted, bitcoin is minted as a virtual token by computers, through a process called “mining”.
Some investors see bitcoin as the currency of the future. The value of one bitcoin has risen from around $10,000 two years ago to over $33,000 at the time of this publication.
Jeff Campbell, who oversees bitcoin mining operations at the Scrubgrass Power Plant in Kennerdell, Pennsylvania, said each of their computers generates an average of $30 a day mining bitcoins.
“These are computers that are only designed to do one thing. They are designed to work as fast as possible around the clock,” he told ABC News Live.
Computers at a bitcoin mining operation need a lot of power both to run and to run the fans that keep them from overheating. According to an estimate by the Cambridge Center for Alternative Finance, annual global bitcoin mining uses more electricity than the entire nation of the Netherlands.
Climate activists wonder if the growth of cryptocurrency mining operations could generate more carbon emissions and create a new market for fossil fuels at a time when the world tries to reduce energy consumption and reduce carbon emissions as quickly as possible.
Under fire for their emissions and reliance on fuels like coal and natural gas, some bitcoin mining companies in the United States are transitioning to more renewable types of energy like solar or wind energy.
Stronghold Digital Mining, owner of the Scrubgrass plant, found its source of energy in the form of coal waste, abundant in this 221-acre pit just outside Pittsburgh. Coal waste is a combination of rock, coal, and other materials that have been deemed unfit for combustion and left abandoned since the 1970s when coal mines in the area were closed.
There are 220 million cubic meters of coal pits like Russellton’s on 9,000 acres in Pennsylvania, according to testimony from Pennsylvania Department of Environmental Protection director Patrick McDonnell. The agency says the pits are causing environmental problems like acid leaching into nearby rivers and streams. There are also 40 ongoing fires in waste coal pits across the state that can release carbon dioxide and other pollutants when burned, according to a document from a waste coal industry group.
The entrepreneur behind Stronghold, Bill Spence, says that while burning coal waste isn’t the cheapest form of energy, the bitcoin operation keeps the plant viable thanks to its demand. electricity constant. This helps it achieve its goal of reducing toxic waste piles statewide, Spence said.
“What cryptocurrency and bitcoin have done for us is they have allowed us to continue the work that this powerhouse is doing as an environmental factory cleaning up the coal waste, the remnants of the mining industry here in the state of Pennsylvania,” he told ABC. .
The Pennsylvania Department of Environmental Protection says the state has benefited from coal-fired power plants because the state has limited funding to clean up piles and address environmental issues.
“Waste coal-fired units burn waste coal to generate electricity, reducing the size, number and impacts of these otherwise abandoned batteries allowed to mobilize and negatively impact the quality of the air and water in Pennsylvania,” press secretary Jamar Thrasher said in an emailed statement.
Pennsylvania provides up to $20 million a year in subsidies to coal-fired power plants, and Thrasher said the state is including their CO2 emissions in the state’s carbon budget to help them compete with forms of carbon. cheaper energy like natural gas.
Coal waste is burned in a different process than traditional coal, but still releases carbon dioxide which contributes to the warming of the atmosphere. The EPA says the type of coal waste found in Pennsylvania also releases more acid gas and sulfur dioxide than other types of coal.
Stronghold says they implemented technology to capture pollutants like sulfur dioxide or methane emissions from their plant, but according to publicly available data, they still released about 365,000 metric tons of sulfur dioxide. carbon in 2019, equivalent to around 80,000 cars on the road. for one year, according to an EPA emissions calculator. The facility also released more than 1,000 metric tons of methane, a potent greenhouse gas, and nitrogen oxides, or NOx, which contribute to air pollution.
Rob Altenburg, director of environmental nonprofit Penn Future, said bitcoin is “useless by design” and there are better alternatives to generating this energy than burning waste coal.
“They don’t eliminate pollution. They move pollution. They move pollution from the earth and they move it into the air,” Altenburg told ABC News.
And because waste coal contains less coal than would typically be used to generate energy, more must be burned to create the same amount of energy, which could generate more CO2 emissions. and air pollution.
“The dirtiest power source we have in the state should be your last choice to generate that electricity,” he said.
Altenburg said that instead of burning waste coal, the state and federal government should provide more funds to move the materials to lined landfills where they can no longer contaminate soil or water.
The federal infrastructure bill allocated $11 billion to clean up abandoned mines, some of which could be used to clean up coal waste in Pennsylvania.
Spence acknowledges that Stronghold’s operations generate carbon dioxide and that their operation is not perfect, but they are trying to improve further by testing technology to capture the carbon they emit. And he said the bitcoin operation helps him fund his efforts to use waste coal that would otherwise go nowhere on its own.
“I don’t think we should stop what we’re doing to get the perfect one,” Spence told ABC.
“Let’s evolve towards perfection.”
Seiji Yamashita of ABC News contributed to this report.
