That reduction goal, known as 30×30, is enshrined in the Global Methane Pledge, which the U.S. and 154 other countries have signed. Energy Vision’s new report, Meeting the Methane Challenge, offers the first clear roadmap of what the U.S. can do to reach 30×30.
Methane is 84-87 times as potent a greenhouse gas as carbon dioxide over a 20-year period, and it’s responsible for about a third of global warming since the start of the Industrial Revolution. Cutting methane soon is the biggest lever available to slow global warming. EV’s report provides unique insights into how much methane the U.S. can cut from two huge sources: the oil and gas sector and organic wastes.
Options to Cut Methane in the Oil and Gas Sector
Energy Vision calculated that the largest methane reduction option would be full compliance with EPA’s new emissions regulations (the “New Source Performance Standards” or NSPS) across virtually every aspect of oil and gas production; these took effect on May 7th. Full compliance with the NSPS by 2029 is by no means guaranteed in the face of intense opposition from the oil and gas industry, but it would take 17.5% off total U.S. methane at a cumulative capital cost (capex) at $20.7 billion.
If the NSPS are blocked or weakened by lawsuits, another option for major methane reduction is to plug all 700,000 low-producing “stripper wells.” These account for ~80% of wells by number but produce only 6% of the country’s oil and gas – and half the methane emissions from oil and gas production. Plugging them would take 10.7% off total U.S. methane at a capital cost of $28.1 billion.
If plugging all stripper wells is politically infeasible or logistically impractical, then we found that plugging just the leakiest 5% of stripper wells – some 35,000 – would have the most bang for the buck of any option. It would cost just $2.1 billion in capex to take 5.4% off total U.S. methane.
By contrast, we found that the smallest impact and highest cost would come from plugging all 2.1 million abandoned oil and gas wells. This is a daunting and important task, but even full completion would take just 1.1% off total U.S. methane, at an estimated capex of $130.7 billion.
Diverting Organic Wastes to Anaerobic Digesters
Even if the oil and gas sector fully complies with the NSPS, cutting U.S. methane by 17.5%, where would the rest of the gains come from?
The answer: tackling the massive methane emissions from decomposing organic wastes.
Energy Vision calculated the country’s achievable potential for processing organic wastes in airless tanks called anaerobic digesters (ADs). ADs turn organic wastes – food scraps, manure, and wastewater – from climate liabilities into assets. Instead of the wastes releasing methane into the atmosphere as they decompose, ADs capture this methane. It can then be used to generate electricity and heat buildings.
The methane can also be upgraded to renewable natural gas (RNG), a sustainable fuel which requires no drilling. RNG is a commercially viable strategy for displacing fossil fuels in “hard to decarbonize” sectors, namely heating some older buildings, powering heavy industries, and fueling heavy-duty buses and trucks.
The Top Targets for Cutting Methane from Organics: Food Waste and Manure
Energy Vision found that the single largest opportunity for organic waste, with the biggest bang for the buck nationwide, is to divert food waste from landfills to ADs. Half of all food that is currently discarded is edible and should be redistributed. Our analysis is thus only based on diverting the other, inedible half of food waste to ADs. We found that building ~680 ADs to process municipal and industrial food waste would cut 7.5% of total net U.S. methane per year at a total capex of ~$31.7 billion.
We found that the second-most impactful feedstock for ADs is manure. Energy Vision calculated that building ~4,000 additional ADs to process dairy and swine manure would cut total net U.S. methane ~6.1% annually at a total capex of $42.5 billion.
In short, building roughly 4,700 ADs to process food waste and manure would cost about $74.2 billion and would cut 13.6% of total U.S. methane per year. On average, each project would take roughly 2-6 years to build, so many could be operational by 2030.
The Bottom Line
Together, building the ~4,700 ADs plus various options to plug oil and gas wells approach 30×30, and the ADs plus full compliance with the NSPS regulations even reach a 31.1% methane reduction by 2030 (see chart below)! And even if oil and gas methane reduction efforts get delayed or weakened, AD development doesn’t face the same legal/regulatory challenges and could proceed regardless. It’s time that ADs receive the attention they deserve as a critical piece of meeting the methane challenge.
