Natural gas has long been promoted as a “bridge fuel” — a cleaner alternative to coal and oil that can ease the transition to renewable energy. But how clean is it, really?
What is “Natural Gas”?
“Natural gas” consists of 70-90% methane (CH4), with a few other gases and some non-hydrocarbon elements mixed in. It’s processed to remove impurities before being used as a fuel.
“Natural gas” got its name to distinguish it from gas made from coal in the 1800s. It occurs naturally in underground deposits and is extracted via drilling and fracking. But there isn’t anything “natural” or nature-based about extracting it or burning it as a fuel.
As US Energy Secretary Chris Wright likes to point out, burning methane gas is much cleaner than burning wood, dung, old tires, agricultural waste, used motor oil and heating oil. Wright loves to talk about how much cleaner the air would be in developing countries (especially in Africa) if they switched from dirtier fuels to methane gas. And he’s correct in saying that.
What Wright doesn’t like to say is that because of its molecular structure, methane traps more heat in the atmosphere per molecule than CO2. Much more—methane is 80 times more potent as a greenhouse gas than CO2.
Nor does Wright like to talk about the by-products of fracking—the process by which much natural gas is extracted from the earth. Those by-products include vast underground waste ponds contaminated with toxic chemicals, and unstable ground where these waste ponds are located. The pollution caused by fracking is significant. I prefer to call natural gas “fracked gas” or “methane gas” because of the pollution it causes.
Gas at oil wells and refineries is often flared into the sky. This is a wasteful practice that causes emissions of CO2, methane and soot. There should be minimal methane emissions if a flare is designed, maintained and operated correctly, but that is not always the case.
The Really Bad News
Far worse than burning or flaring methane gas are leaks of raw, unburned methane. Methane is leaking from thousands of oil wells, fracking sites, pipelines and refineries around the world.
The problem with unburned methane is that it escapes into the atmosphere where it forms a thick, reflective layer which keeps heat from escaping. This layer then reflects that heat back towards earth, warming the air we breathe, warming the oceans, and creating the storms, droughts and wildfires we are experiencing.
In this way, raw unburned methane is a huge contributor to climate change. According to the International Energy Agency (IEA), methane is responsible for 30% of the rise in global temperature since the Industrial Revolution. The IEA estimates that annual global methane emissions from the energy sector are 130 million tons.
The Biden EPA recognized our methane problem and finalized a rule that aimed for an 80% reduction in methane emissions by 2038. In addition, the Inflation Reduction Act established fees on flaring and methane leaks. And it offered operators incentives to fix them.
Unfortunately, the Republican Congress overturned both the Biden methane rule and the IRA methane emissions program. Trump signed these changes into law.
Going further, the Trump EPA claims that greenhouse gases do not directly affect public health and therefore the agency has no authority to regulate them. You may have seen this referred to as the repeal of the “2009 Endangerment Finding.” That finding is the legal basis for regulating fuel emissions under the Clean Air Act. Courts will decide the case in the near future.
Finally, on August 1 the Department of Energy (DOE) released a report on greenhouse gas emissions. It doesn’t mention methane and says the connection between climate change and greenhouse gas emissions is unproven.
The Good News
Until recently, policymakers and regulators relied on companies and countries to self-report their methane gas emissions.
But now—and here’s where the good news begins—satellites and AI technology have combined to let us to “see” and measure methane emissions more accurately.
Satellites are especially good at detecting “super emitter” events, like one where 40,000 tons of methane were released by a Gulf of Mexico oil platform in 2021. Without satellites, events like this go undetected.
As the technology improves, satellites will allow us to pinpoint leaks and address them. It will also show whether climate policies are working. For example, Climate TRACE is a publicly available website that maps greenhouse gas emissions worldwide and in real time. This kind of satellite and AI technology are just now being incorporated into international policymaking. These technologies have the potential to put real teeth into future regulations.
And there’s more good news. Although raw methane is 80 times more potent than CO2 in its greenhouse gas effects, it breaks down much more quickly—in about 12 years, while CO2 can take thousands of years to fully break down or be absorbed.
Because CO2 takes so long to go away, scientists and environmentalists have focused most of their attention on reducing CO2 emissions. This is right and important.
As a result, methane emissions haven’t been given as much attention. But here’s a radical idea: why not tackle raw methane emissions now?
According to the UN, cutting human-caused methane leaks by 45 percent in the current decade would keep global warming beneath the 1.5 degrees threshold established by the Paris Agreement.
Eliminating methane leaks would cut greenhouse gas emissions and slow climate change very quickly. Doing so would buy us valuable time–time we need to transition from fossil fuels to renewables.
This is why numerous government and non-governmental organizations around the world are tackling methane emissions. 50 oil and gas companies have pledged to eliminate methane leaks by 2030. 159 countries and the EU have signed the Global Methane Pledge with a goal to reduce methane emissions by 30% from 2020 levels by 2030. Many other groups are actively working on the issue.
Even Secretary Wright is on board. In a recent address to oil and gas leaders, he declared that “eliminating venting, flaring and methane leaks should be a priority.”
So back to my original question—how clean is natural gas, really? It does burn cleaner than coal and oil. But if the methane life cycle from extraction to burning is considered, it’s not clean at all. Pollution from extraction and leaks makes it one of the deadliest greenhouse gases. Still, despite setbacks from the Trump EPA, the DOE and Congress, work to reduce the harm caused by this so-called “natural” gas is ongoing.
Teaser image credit: Ground-level flaring of gas in North Dakota. By Joshua Doubek – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27166619