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A bitcoin rush and purple maize

by Jessica Morrison
April 25, 2021 | A version of this story appeared in Volume 99, Issue 15


Bitcoin flickers and flares

A gold coin with bitcoin symbol surrounded by flames.
Credit: Shutterstock
Hot topics: Some in the oil and gas industry want to use flare gas to fuel cryptocurrency mining.

Last year’s decline in natural gas consumption has fired up some in the oil and gas industry to explore a different kind of resource extraction—one that uses computers to mine for digital currency. Quartz reports that since the pandemic began, a handful of gas companies in the western US have tapped excess flare gas—an environmentally contentious by-product of oil extraction that’s typically burned off—to power generators that supply cheap electricity to data centers that mine bitcoins, a cryptocurrency.

Cryptocurrency mining, which involves using computers to solve cryptographic equations, has been criticized for its outsize energy requirements. According to researchers at the Oak Ridge Institute for Science and Education, bitcoin mining consumes more than twice the energy required to mine an equivalent value of copper, gold, or platinum.

EZ Blockchain, a company that sells digital mining infrastructure to gas companies, says its model offers a way to monetize wasted energy and reduce natural gas flaring, and it’s not alone. Denver-based start-up Crusoe Energy Systems has raised more than $70 million in 2 years to expand its digital flare-mitigation technology and services.

Does the success of these companies forecast a shift to crypto mining for oil and gas drillers? Texas A&M University’s Gunnar Schade, an atmospheric biogeochemist, tells Newscripts, “My crystal ball is as good as yours with regard to whether the industry will pivot toward bitcoin.”

Schade doubts that bitcoin mining at flare sites will catch on enough to significantly reduce emissions of carbon dioxide, methane, and other pollutants. “I do not see this becoming a major mitigation measure,” he says, adding that there are thousands of flares and that it seems unlikely that as many data centers will sprout within the next few years to harvest energy.

But Bitcoin is certainly hot these days. The value of a single bitcoin soared above $60,000 in March, gaining momentum after Tesla, helmed by serial technopreneur Elon Musk, bought $1.5 billion worth of bitcoin. But some would say he’s got money to burn.


More from corn

Purple was once the most prized of pigments, painstakingly extracted from sea snails. But royal purple robes and pretty purple kitty litter might one day get their attractive violet hues from a more common natural ingredient: corn trash. According to a team of Italian researchers, waste from purple corn products could be recovered for use as natural dye and animal litter, reducing corn waste to virtually nothing.

Purple corn cobs, purple pet litter, and fabric dyed purple.
Credit: Patrizia De Nisi
Purple rain: Waste from purple corn cobs could be used as dyes and pet litter.

Did someone say purple maize? Scuse us while we geek out about plant-based dyes.

Purple corn contains anthocyanins, a group of plant pigments used as food additives to turn our favorite tasty treats brilliant shades of red, purple, and blue. The Newscripts gang is fond of anthocyanins and has written about their colorful additions to our butterfly pea cocktails and our black currant hair dyes.

Researchers at the University of Milan found that inedible purple corn husks and cobs are rich in anthocyanins, but they are usually discarded as waste. The group developed an extraction process that uses water and ethanol instead of acetone, which is costly and toxic (ACS Sustainable Chem. Eng. 2021, DOI: 10.1021/acssuschemeng.0c08717).

The team, led by Fabrizio Adani and Roberto Pilu, reported a multistep biorefinery process that produced a pigmented aqueous extract for fabric dyeing in step 1, a pigmented hydroalcoholic extract for antioxidant and anti-inflammatory nutraceuticals in step 2, and a final solid residue suitable for animal litter in step 3.

Although the Newscripts gang is tempted to make a corny joke, we’ll reach for a bag of colorful tortilla chips instead.

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