Composting vs Methane Capture: A Climate Smackdown

San Francisco compost grows cover crops at the Chateau Montelena winery

Let our journalists help you make sense of the noise: Subscribe to the Mother Jones Daily newsletter and get a recap of news that matters.


Across the pungent world of waste, a climate debate has been raging. Which is better: turning yard clippings and food scraps into compost, or landfilling them and capturing the methane that they release to produce energy?

Last month, I happened across this question while riding in a muddy pickup across the top of Altamont Landfill, a 30-story hill of garbage run by Waste Management, the nation’s largest trash collection outfit. “To me, I think it’s good to have more organics in the garbage,” operations manager Neil Wise told me. Organic matter in landfills generates methane, a potent and flamable greenhouse gas; Altamont currently captures enough methane to power 8,500 homes.

On the other side of this debate is the City of San Francisco, which this week voted to make composting lawn clippings and food scraps mandatory for every city resident. The nutrient-rich product fertilizes more than 200 Bay Area vineyards. Composting advocates worry that outfitting more landfills with “methane wells,” possibly with the aid of carbon offsets created through a climate bill, will detract from those efforts. 

Here’s my take: While capturing methane from landfills is certainly worthwhile, evidence suggests that composting is far better. A nine-year study by the Rodale Institute, to be published in the next issue of Compost Science and Utilization, a peer-reviewed journal, found that applying compost to cropland sequestered a staggering 10,802 pounds more carbon dioxide per hectare each year than farming with conventional manure fertilizer. That’s more than the yearly emissions of a Chevy Impala. “That’s a pretty big deal,” says Rodale research director Paul Hepperly, the author of the study. “When you are composting, you are stablizing the carbon” in organic matter.

And though capturing methane at a landfill also reduces greenhouse gasses, it can’t match composting’s associated benefits. Compared to raw manure, Rodale also found that compost applied to farmland led to a 600 percent reduction in nitrate leaching, which can pollute steams and groundwater, and improved the soil’s retention of water by a factor of three. “This relates to looking at things wholistically,” Hepperly said, adding that the ultimate goal should be an “agricultural system that invests more in our environment and takes less out of our resources.”

 

DOES IT FEEL LIKE POLITICS IS AT A BREAKING POINT?

Headshot of Editor in Chief of Mother Jones, Clara Jeffery

It sure feels that way to me, and here at Mother Jones, we’ve been thinking a lot about what journalism needs to do differently, and how we can have the biggest impact.

We kept coming back to one word: corruption. Democracy and the rule of law being undermined by those with wealth and power for their own gain. So we're launching an ambitious Mother Jones Corruption Project to do deep, time-intensive reporting on systemic corruption, and asking the MoJo community to help crowdfund it.

We aim to hire, build a team, and give them the time and space needed to understand how we got here and how we might get out. We want to dig into the forces and decisions that have allowed massive conflicts of interest, influence peddling, and win-at-all-costs politics to flourish.

It's unlike anything we've done, and we have seed funding to get started, but we're looking to raise $500,000 from readers by July when we'll be making key budgeting decisions—and the more resources we have by then, the deeper we can dig. If our plan sounds good to you, please help kickstart it with a tax-deductible donation today.

Thanks for reading—whether or not you can pitch in today, or ever, I'm glad you're with us.

Signed by Clara Jeffery

Clara Jeffery, Editor-in-Chief

payment methods

We Recommend

Latest