When Dominion Energy announced that it, along with Duke Energy, was killing the Atlantic Coast natural gas pipeline project, and the Richmond, Va., company was selling its midstream natural gas business to Berkshire Hathaway, Dominion also made a pitch that it would invest heavily in “renewable natural gas” (RNG) going forward.
Dominion CEO Tom Farrell said, “Over the next 15 years we plan to invest up to $55 billion in emissions reduction technologies including zero-carbon generation and energy storage, gas distribution line replacement, and renewable natural gas.” Dominion and other investor-owned utilities, including SoCalGas, have long been touting RNG as a claimed zero carbon approach to using methane to generate power and provide heat as they tentatively shy away from “fossil natural gas” as polluting. But they are going to continue to burn a lot of conventional gas to generate power and sell it to retail customers for heating and industrial processes.
The day after the announcement, Forbes magazine published a breathless article praising Dominion, with the headline, “How Buffet’s Pipeline Deal Is Doing Double Duty Helping Dominion Energy Turns Acres Of Manure Into Clean Power.” A year earlier, Yale University’s Yale Environment 360 website published an article asking, “Could Renewable Natural Gas Be the Next Big Thing in Green Energy?”
Just what is “renewable natural gas” and is it a way to replace gas drilled from under the earth to gas produced on the surface? And it is the case for it solid?
Renewable gas, AKA biogas or “synthetic natural gas,” is a product of turning animal and vegetative waste into methane, then upgrading it to pipeline quality, and burning it to make electricity. That is in use today. An alternative approach, not yet practical, is to use carbon dioxide captured from the air and hydrogen produced by electrolysis using power, probably nuclear-generated electricity, combining the two elements in a methanization reaction to produce methane.
For Virginia-based Dominion, RNG is a natural. The country’s largest pork producer, Smithfield, is located in the Old Dominion. As the Forbes article said, Smithfield will turn its pig manure lagoons into methane producers, capturing the resulting of the natural decomposition. The magazine said, “Dominion will siphon the pig gas out of these anaerobic digesters, inject it into interstate pipelines and sell it to green-minded customers looking to cut their carbon footprints. The end result is arguably the cleanest electricity in the nation, says Dominion Chief Operating Officer Diane Leopold.”
Not so fast, says the Sierra Club and the environmental movement’s in house law firm, Earth Justice. In an analysis released today, the greens say RNG, which they rename “fossil gas alternatives” or FGAs, is a “myth for building decarbonization.” Rather, they advocate moving away from gas entirely and toward electrification.
The analysis — Rhetoric vs. Reality: The Myth of “Renewable Natural Gas” for Building Decarbonization — raises four major objections to biogas:
* The potential supply of gas from farms and fields is tiny. “The gas industry’s own research found that after two decades of ramping up supply and production, FGAs could only replace 13% of the existing demand for fossil gas.”
* Cost is prohibitive. “High production costs mean FGAs range from 4 to 17 times more expensive than fossil gas.”
* A mixed environmental record. FGAs “can exacerbate air and water pollution impacts in nearby communities. When methane is intentionally produced, leakage throughout the distribution process can result in increased emission,” as methane is a potent greenhouse gas, although not as long-lived as carbon dioxide.
* Health impacts. Combustion-based fuels have inherent health issues, as they “produce toxins that harms the health of people living, working, or learning in these buildings and also contribute to local air pollution through continued emissions of NOx and other combustion byproducts.”
The green analysis argues that “zero-emission appliances powered by renewable energy can heat our buildings more efficiently and protect our health.” Earth Justice policy analyst Sasan Saadat said, “It would be foolish to stall the all-electric transition in favor of riskier and unscalable solutions like fossil gas alternatives just because they serve the gas industry’s interests.”
How will all this work out? That question will be decided by market forces, state regulation, and federal responses. The outcome is not clear.
But one veteran of the energy technology wars over the past 40 years, commented, “It sounds to me a lot like clean coal technology. How did that work out?”
— Kennedy Maize