FILE - In this Wednesday, Aug. 20, 2014 file photo, Jon Rumion, background left, talks with Michael Cargill at Central Texas Gun Works in Austin, Texas. Bitcoin has crossed the $40,000 mark, extending on a huge rally that started three months ago, Thursday, Jan. 7, 2021. (AP Photo/Eric Gay, File)

GRUNDY CENTER — About 8 miles west of here is a white Quonset hut that hums with the sound of industrial fans.

Unlike other rural outbuildings equipped with fans, this one doesn’t house hogs. It’s stacked with computers that spend all day and night working complex mathematical problems that create bitcoin, the most well-known cryptocurrency.

“I knew there was a place out there,” said Jill Krausman, owner of the Landmark Bistro in Grundy Center, who doesn’t know much about the site other than if an employee stops in for lunch. “I don’t have enough knowledge about it. It hasn’t affected me.”

The Cedar Rapids Gazette reports that this nondescript facility is one of the first — if not the first — large-scale cryptocurrency mining site in Iowa. But the company wants to expand with five more locations in Eastern Iowa, capitalizing on wide-open spaces, low property taxes and cheap electricity.

Cheap electricity is especially important because crypto mining uses a lot of juice. The Grundy County site uses more electricity than all the residential customers in Grundy Center, population 2,800, combined.

The industry’s massive energy use at a time when the world is trying to curb climate change should be a red flag to Iowa utilities and residents, said Kerri Johannsen, Energy Program director for the Iowa Environmental Council.

“There is a larger fundamental question about why we need to use energy in the first place to create cryptocurrency,” she said.

Bitcoin was created in the late 2000s, after the Great Recession, as a way for people to send money directly to each other without a bank or third party. Other cryptocurrencies, such as ethereum and litecoin, have followed.

Bitcoin transactions are verified and monitored by independent computers running a secure algorithm to solve blocks of numbers that represent groupings of transactions. These computers, or “miners,” race to solve each block with the payout being the next block of bitcoins, which is worth hundreds of thousands of dollars.

The Grundy County site is too small to solve blocks on its own, so miners there work as part of a mining pool that pays out a daily rate based on the amount of work, or “hashing” the computers do, explained J.P. Baric, founder and chief executive officer of the MiningStore, which owns the site.

“Bitcoin is important to me because it’s a monetary system that can’t be influenced by the government and it can’t be changed,” he said.

Baric, 24, dropped out of North Carolina State in 2017 to move to Texas — first Houston, then Austin, which he calls a “crypto mining heaven.” With his parents and grandparents, Baric invested $1 million to start the MiningStore, which owns and operates the Grundy County site as its flagship facility.

Right now, each of the site’s 1,900 computers mines $17 per day, but that amount fluctuates with the value of bitcoin. It’s been as high as $35 a day. But at current rates, the site makes about $32,000 a day. The power bill is over $5,000 a day, Baric said.

Baric found the Iowa site through a Colorado economic development group that identifies areas with low energy costs.

“It doesn’t surprise me they set up shop in Grundy County because they have really low- cost energy there,” said Jim Martin-Schramm, a Luther College emeritus professor who focuses on energy and climate policy.

At 4.05 cents per kilowatt-hour, the Grundy County REC has some of the cheapest industrial electricity in the state, according to filings with the Iowa Utilities Board. The MiningStore bought one acre of land in 2019 right next to an electrical substation.

Magnus Anderson, the MiningStore’s Grundy County site manager, explains how electricity moves through a 1,500-kilowatt transformer underground directly to the site. The company’s contract with the REC says six months of the year the MiningStore will agree to temporarily power down when there is peak electrical usage, such as on hot summer days.

“It’s a load vessel for the grid,” he said of the mining site. “We use it (electricity) until everybody else needs it.”

The site uses 6 megawatts of power during operation, which is 24/7 unless part of the system is undergoing repairs.

To put this in perspective, Luther College, with 1,800 students, in Decorah, uses about 2 megawatts during most of the year, rising to 2.8 megawatts in the summer, Martin-Schramm said.

An average Iowa home uses about 11,000 kilowatt-hours of electricity per year, Johannsen said. The MiningStore uses about 54 million kilowatt-hours a year, or the equivalent of 4,900 houses.

“All of Grundy County in the census has 5,146 households,” she said. “We’re talking about 95 percent of the households in Grundy County.”

So where does the power come from?

Grundy County REC is one of nine rural electric cooperatives and one municipal cooperative that own Corn Belt Power Cooperative, based in Humboldt and serving 41 northern Iowa counties. Corn Belt owns the nine substations within Grundy County REC, including the one that powers the MiningStore.

Corn Belt’s power mix in 2019 was about 50 percent coal, 18 percent purchased power, 15 percent renewables and smaller shares of natural gas, hydro and nuclear, according to the coop’s website.

A half-dozen wind turbines are visible from the MiningStore site, but those turbines are owned by MidAmerican Energy and do not power the crypto mining facility, said the REC’s General Manager Mike Curtis.

The cooperative’s electricity sales to large commercial and industrial customers more than doubled from 16.5 million kilowatt-hours in 2018 to 36.9 million kilowatt-hours in 2020, which Curtis said is largely due to the MiningStore.

For bitcoin to become a viable worldwide currency, some environmental groups say it must slash its energy use.

A group called Change the Code Not the Climate says changing the “proof of work” required to validate transactions to a “proof of stake” — meaning miners pledge coins to verify transactions — would cut energy use by 99 percent, according to a March article in the Guardian.

“Since cryptocurrencies are too volatile to be used as an actual currency, people treat it as a sort of investment scheme,” wrote Jon von Tetzchner, co-founder and CEO of Vivaldi Technologies, in a Jan. 13 blog post.

“The problem is that to extract actual money from the system you have to find someone willing to buy the tokens you are holding. And this is only likely to happen as long as they believe they will be able to sell them on to someone who’ll pay even more for them. And so on, and so on.”