โRenewable natural gas,โ or RNG,ย is an alternative gasย fuelย that comesย from landfills,ย manure, or synthetic processes. That’sย opposed to theย fossil gas that drillers traditionally pump outย of underground reserves in oil and gasย fields.
With โrenewableโ in the name, itย may sound like a promising alternative to the fossil-based โnaturalโย gas commonly used for heating and cooking in buildings. According to a new report from Earthjustice and Sierra Club, however, these fuels pitched as โrenewable โ andย environmentally friendly alternatives to fossil gas amount to a PR campaign meant to distract from efforts to convert the building sector to all electricย power.
The report, published July 14, argues that RNG is an example of fossil fuel industry greenwashing and is not a viable solution for simply replacing fossil gas in buildings. According to the report, RNG is touted by gas utilities for the purpose of countering building electrification policies that restrict the use of gas in buildings for uses like heating, hot water, and cooking. Converting buildings to all-electric usage is recognized as a key climate strategy to shift away from fossil fuels, because electricity can be generated from a variety of sources that do not produce globe-warmingย emissions.
In this report, Earthjustice and Sierra Club, groups that advocate for climate action including building electrification policies, examine the potential for what the gas industry promotes as โrenewableโ natural gas to actually decarbonizeย buildings. The environmental groupsโ report finds that RNG, or what they call โfossil gas alternativesโ (FGAs), are limited in supply, have generally high production costs, can exacerbate air and water pollution during production, and result in the same health impacts as any combustion-basedย fuel.
The gas industry acknowledges the shortcomings of these fuels, as internal documents reveal. But as the report explains, the industry is publicly promoting them as a clean alternative to the electrification of buildings in order to maintain their core gas business, which is threatened by building electrificationย broadly.
โWe find a pattern of talking points and lobbying efforts that leverage [fossil gas alternatives]ย as a means of maintaining a gas-based heating system and stalling the transition away from fossil fuels,โ the reportโs executive summary states.
โThis is not unfamiliar territory: The tactics come from the same energy industry playbooks that have dismissed and obfuscated the threat of climate change,โ the summary continues. โIn this case, the widespread adoption of a proven and cost-effective means of fighting climate change is being attacked and stalled in order to protect fossil fuel financial interests โฆ Policymakers must see beyond the gas industryโs rhetoric around FGAs and acknowledge the reality of their high costs, limited supply, and environmentalย risk.โ
What is ‘Renewable Natural Gas’ย and Is it Carbonย Negative?
The two types of fossil gas alternatives, or โrenewable natural gas,โ are biogas and syntheticย gas.
Biogas is derived from organic materials like crops or animal waste and generally produces methane โ a potent greenhouse gas โ from processes such as anaerobic digestion. Biogas also goes by โbiomethane.โ Synthetic gas, on the other hand, comes from electricity that is converted into gas. That process involves adding carbon dioxide to hydrogen molecules through a step calledย โmethanation.โ
In other words, a lot of renewable natural gas involves intentionally producing methane. A small amount of RNG captures methane that would otherwise escape into the atmosphereย (from landfills, for example). As a result,ย RNG promoters, such as the southern California gas utility SoCalGas, claim it is โcarbonย negative.โ
Emily Grubert, a researcher at Georgia Tech who is studying RNG from a methane standpoint, recently authored a study showing that scaling up RNG could actually result in more methane leaking into the atmosphere, rather than having the desiredย โcarbon negativeโย effect.
Arg 1:
At scale, most RNG is likely to come from intentionally produced methane (even if itโs produced from waste).
That means manufacturing a potent GHG. Thus: leakage = climate additional.
We know these systems willย leak.
โ Emily Grubert (@emilygrubert) May 14, 2020
โA very small amount of RNG could be carbon negative. I think the missing piece of the story is that there isn’t enough carbon negative RNG to meaningfully displace fossil natural gas, so for systems at sizes advocates are discussing, a lot of the renewable methane would need to be produced on purpose,โ Grubert told DeSmog byย email. โThat means you’re manufacturing a potent greenhouse gas. We know that gas systems leak, so putting intentionally produced methane into a leaky system will contribute to climate change. The overall climate intensity of the system ultimately depends on the balance of intentionally produced vs. waste methane inputs, but itโs pretty clear that we can’t replace the entire fossil natural gas system with carbon negative, or probably even carbon neutral, RNG.โ
The Earthjustice and Sierra Club report also points to thisย potential methane problem with renewable natural gas. โGenerating new sources of methane where none would ordinarily occur can lead to an overall increase in [greenhouse gas emissions],โ the reportย explains.
Other Limitations of RNG
Despite its โrenewableโ label, non-fossil gas is currently limited in its capacity to fullyย swap out conventional gas. According to the new report, โEven the gas industryโs own analysis finds there is an insufficient supply of carbon-free gas to meet anything more than a small portion of current gas demand. According to a study by the American Gas Foundation (‘AGF‘), even after fully ramping up the production of renewable gas, FGAs could supply between just 6 percent to 13 percentย of current gas demand, clearly falling short of the goal of net-zero emissions and requiring fossil gas to make up theย difference.โ
RNG is also relatively expensive to produce, according to the report. These types of non-fossil gases further โcontribute to local air pollution through continued emissions of NOx [nitrogen oxides] and other combustion byproducts,โ the reportย notes.
Earthjustice and Sierra Club argue that renewable natural gas is better suited for uses in harder-to-decarbonize sectors such as high-heat industrial production or heavy-duty transport like aviation andย shipping.
โUnder closer scrutiny, what we see is that fossil gas alternatives might be able to play a role in certain segments of our society to decarbonize them,โ Sasan Saadat, a research and policy analyst at Earthjustice and a co-author of the report, told DeSmog in an interview. โScaling them to heat all of our buildings in the way we use fossil gas now is not a viableย solution.โ
‘PR Campaign’ย to Protect Gas Industryย Profits
Internal documents reveal the gas industry acknowledges the shortcomings of RNG but is publicly promoting it anyway as part of a broad strategy to fight buildingย electrification.
An internal set of American Gas Association meeting notes from March 2018, obtained by watchdog group Climate Investigations Center (CIC), describes the gas industry trade associationโs interest in promoting RNG to environmental advocates who are opposed to gas expansion in order to โmitigate the oppositionโsย fervor.โ
Another internal document that CIC obtained reveals that a gas industry insider acknowledged in an email to other gas utility employees that he believes RNG โwill not sustain our industry at its presentย size.โ
According to the Earthjustice and Sierra Club report, the gas industry and gas utilities have pushed misleading claims about the promise of RNG while railing against the costs of electrifyingย buildings.
The southern California gas utility SoCalGas, for example, last year claimed in a press release: โUsing renewable natural gas in buildings can be two to three times less expensive than any all-electric strategy โฆโ The report explains that this claim may not be true, referencing California Energy Commission analyses finding that โelectrification is the cheapest and lowest-risk option to decarbonize the stateโsย buildings.โ
Februaryย 8, 2011,ย Southern California Gas Co. and the city of Escondido announced the official start-up of a renewable natural gas projectย using wastewater biogas. Credit:ย Genevieve Prentice,ย CC BY–SAย 2.0
Electrification of buildings, however, directly threatens the business model and profits of gas utilities, as the report points out. The risks are particularly existential for gas-only utilities, as opposed to utilities that service both gas and electric. โThe movement towards all-electric buildings โฆ poses a new long-term financial threat to the gas industry,โ the reportย argues.
The gas industry has mobilized against this perceived threat by initiating front groups, using a strategy known as โastroturfing,โ or creating fake grassroots support, in this case for gas use in buildings. Some of these front groups, as the report notes, have cropped up in California, the Pacific Northwest, Hawaii, andย Massachusetts.
Advocatingย for RNG use in buildings appears to be part of this broader strategy to counter the trend towards electrifying buildings, concludes the report. After all, if the building sector phases out gas usage for heating and cooking, the gas industry stands to loseย profits.
Dominion Energy and SoCalGas, gas utilities that both promote RNG, did not immediately respond to a request for comment on this characterization of gas utilitiesโย strategy.
โIn order to insist that we continue to rely on their business model, [gas companies] are going to tell us about things like renewable natural gas,โ Earthjusticeโs Sasan Saadat said. โWe need to take a close look at what these greenwashing tactics actually have toย offer.โ
As the Earthjustice and Sierra Club report concludes: โThe gas industryโs well-documented campaign of skewing facts, misleading consumers, and branding [fossil gas alternatives] as a renewable, sustainable energy source must be recognized for what it is: a PR campaign to protect the industryโs financial interests and preserve a business model that is incompatible with achieving a net-zero emissionย society.โ
Energy politics writerย David Roberts made the same argument in a Vox story published earlier this year. โRNG is not a viable alternative for decarbonizing buildings,โ Roberts wrote. โIt is a desperate bid by natural gas utilities to delay their inevitable decline. Policymakers would be foolish to fall forย it.โ
Main image:ย Februaryย 8, 2011,ย Southern California Gas Co. and the city of Escondido announced the official start-up of a renewable natural gas projectย using wastewater biogas. Credit: Crop of original byย Genevieve Prentice,ย CC BY–SAย 2.0
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