Companies in the U.S. natural gas industry have begun to scale up a program to sell methane that’s recycled from sources like hog-feeding farms and sewage plants as a replacement for natural gas drawn from wells.
It offers an opportunity to reduce a potent greenhouse gas while creating a source of revenue for the growing number of companies, cities and farmers becoming engaged in the budding process.
A “methane tracker” report released in January by the International Energy Agency calculated that the warming power of the invisible and hard-to-detect gas can be as high as 87 times more powerful than carbon dioxide during its first 20 years of life. The amount of methane circulating in the atmosphere is 2.5 times bigger than it was in the preindustrial age, the report said.
Because natural gas, which chemically can amount to roughly 98% methane, is likely to remain a major energy source internationally, reducing methane emissions is a “pivotal element” in whether the world can avoid more serious global warming, the IEA noted.
The report came with some ominous math: Human-caused methane emissions account for 60% of the gas circulating in the atmosphere. The largest source is agriculture, which is “closely followed” by the energy sector, where natural gas production and leaky pipelines are big contributors.
So what’s the main source of recycled methane that gas companies are beginning to cash in on? It boils down to manure, from humans and animals.
“Poop is gold today,” Randy Jordan, owner of a Massachusetts dairy farm, recently explained to a Boston television reporter.
The poop made by his 800 Holstein cows was mixed with food waste that was collected from supermarkets and dairies by Vanguard Renewables, a Wellesley, Mass., company. It loaded the mess into a fat, rubber-domed silo, called an anaerobic digester, that it built on Jordan’s farm. The waste was then mixed up and heated for a month.
“They function like a giant cow’s stomach,” said John Hanselman, chairman and CEO of Vanguard, which was started with a chain of methane-producing farms in New England.
The enzymes and methane from the manure helped break down the food. That released more methane. The result, after the gas was purified and concentrated to pipeline standards, was enough natural gas to power and heat 1,600 homes. It raised Jordan’s income by between 15% and 25% per cow, Vanguard estimates.
“To me, this is a no-brainer,” said Michael Bakas, summing up another variant of the growing methane recycling business.
He is executive vice president of Ameresco, a renewable energy and efficiency company in Framingham, Mass. One of its specialties is building plants to collect and purify methane from municipal sewage treatment plants, which deal with human manure.
For years, a sewage treatment plant in Phoenix had collected methane in a pipe and then flared it into the air.
The flame broke down the methane but sent a plume of CO2 into the sky. Last year, Ameresco built an adjoining facility that purified the methane, compressed it and then pumped it into a natural gas pipeline.
The system can produce 600,000 cubic feet of natural gas each year. It earns $1.2 million in annual revenue, to be split by Phoenix and the suburbs that own the plant, and is now the largest sewage recycler in the United States.
Kate Gallego, the mayor of Phoenix, noted that the result helped the area’s economy. It also nudged the city much faster toward its goal of reducing greenhouse gases.
That’s the selling point that makes this approach different, explained Bakas in an interview.
Phoenix made money from manure, but the alchemy was richer than that. Its recycling process, when measured in reduced emissions, amounts to taking 70,452 cars off the road.
For the growing number of countries, cities, states, companies and universities that are setting greenhouse gas goals, reducing methane emissions can be a much faster and more lucrative way to get there, Bakas said.
Methane leakers amount to a “great resource,” but he worries that more environmentally conscious Western states such as California and Oregon will make most of the deals.
“New England will be left out in the cold on this stuff,” Bakas said.
He was right about the tendency but wrong about the buyers.
The current champion of making deals around manure recycling is Dominion Energy Inc. of Richmond, Va., a utility that sells electricity or natural gas to 7.5 million customers in 18 states. It announced in February that its goal is to reach “net zero” greenhouse gas emissions by 2050.
Dominion, the fourth-largest natural gas supplier in the United States, began backing away from drilling for natural gas 10 years ago by buying more of it from other suppliers. It concentrated on fixing older pipes and replacing equipment such as valves, fittings and joints, and changing maintenance practices that were venting methane.
“It was part of the way things were designed,” recalled Aaron Ruby, manager of media relations for Dominion, who said the result so far of all these fixes was a reduction of methane emissions by 25%. He said the company plans to cut 65% of its 2010 emissions by 2030.
“When you add it up across 100,000 miles of pipeline, these small emissions add up to large values across the entire system,” Ruby said.
Minimizing losses was just a start. The next step was to begin putting a new product in the repaired pipelines, one that had been discussed in the U.S. industry for years.
Some companies called it biomethane because it was collected from outside sources of methane, such as manure. The industry gave it a more appealing name: renewable natural gas, or RNG.
Dominion’s next goal was getting manure. Its first big step came in November 2018. It formed Align, a joint venture with Smithfield Foods Inc., the world’s largest hog producer, located in Smithfield, Va., to explore the RNG possibilities in hog manure. Each company put up $250 million.
In August 2019, Dominion and Smithfield broke ground on a joint manure-to-gas processing project in North Carolina. Two months later, they agreed to pursue similar projects across the United States, hoping to produce enough RNG to power 70,000 homes and businesses. They raised their investments to $500 million each.
In December, Dominion plunged more deeply into manure by signing a deal with Vanguard, which had developed what it called a “strategic partnership” with Dairy Farmers of America Inc.
The ambition was to promote anaerobic digesters for cow manure among clusters of dairy farms across the United States. The deal was described in a press release as “the same as taking nearly 100,000 cars off the road or planting 7.5 million new trees each year.”
David Darr, senior vice president of Dairy Farmers, said in a press release that the clusters of multiple farms would each gather the manure from 20,000 to 30,000 dairy cows. “This is a win-win for the dairy farmers and for the environment.”
Just what will come out of these projects—forming in an era when the Trump administration turned its back on climate change solutions—remains to be seen. According to a report released by the American Gas Association, there were “less than a half dozen” projects injecting RNG into pipelines in 2010. Now there are 85.
What’s that smell?
The research predicts that two methods of converting manure and other wastes into RNG, plus a third process that converts hydrogen made from renewable energy into methane, will produce enough low- or no-emissions gas to cover most natural gas consumption by U.S. homes by as early as 2040.
The move to manure was inspired by the Cold War, said Hanselman of Vanguard. A businessman with an interest in environmental issues, he learned that the German government was exploring the idea of making RNG from manure 25 years ago, knowing that its total reliance on Russia for natural gas threatened its energy independence.
Hanselman, who visited manure-to-gas operations in Europe, said the Germans developed the process using large federal subsidies. That wouldn’t work in the United States, he knew, so he paid rent to farmers to put his anaerobic digesters on their land in exchange for their manure. They earned other fringe benefits, including a liquid fertilizer residue from the process that doesn’t smell.
No smell was a big selling point. Dairy farmers traditionally get rid of their manure by spreading it on their farmland. It helps crops grow, but in many suburban areas the smell produced “a lot of pressure on them to leave,” said Hanselman.
He says the joint venture with Dominion will focus on digesters that remove and then break down the manure obtained from the average farmer.
Hanselman’s company is working with another business sector: colleges and companies that value the prestige of “going green.” The list starts with Middlebury College in Vermont, which is 6 miles away from one of Vanguard’s digesters. Vanguard built a pipeline to the college.
Using ordinary renewable energy, like solar and wind power, Middlebury could only offset its own emissions. With its RNG pipeline, Middlebury will soon go “carbon negative” and begin to chip away at the climate impacts of other emitters.
“They’re leaders in higher education, and they want to be as green as they possibly can,” Hanselman said.
Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.