Methane Digester Stocks

Why It Matters

Waste as opportunity

Agricultural, industrial, and human digestion processes inevitably and constantly create organic waste. From residues, excrement, to waste, the spoiling of these materials emits fugitive methane gas as they decompose. 

Humans have a choice: we can keep letting the methane gas escape into the atmosphere, where it creates a warming effect 34 times stronger than CO2 over a hundred-year period, or we can capture the methane as they arise and turn it into usable, clean energy.

Turning methane into energy

The way to turn methane into energy is through methane digesters. First, organic wastes are mixed in an air-tight, oxygen-less tank, where bacteria and other microbes break them down into their component parts. Over the course of days or weeks, biogas rises to the top, while solid digestate falls to the bottom, concentrating nutrients like nitrogen. Biogas is a blend of methane and CO2 that can be used raw or further purified into biomethane, akin to natural gas. 

Biogas can be used for cooking, lighting and heating when used at the household level, reducing demand for wood, charcoal, and dung as fuel sources. When used at an industrial scale, it can displace dirty fossil fuels for heating and electricity generation, and when cleaned of contaminants, it can even be used in vehicles that would otherwise rely on natural gas.

Right now, large methane digesters generate about 100 TWh of electricity around the world, or 0.3% of global electricity generation. Project Drawdown estimates that if methane digesters can be expanded to generate up to 761 TWh, they can help avoid 9.8 gigatons of greenhouse gas emissions by 2050. 

These companies are making it happen.

In the Climate Index, we take all of the companies that capture landfill methane to convert it into energy and exclude those that derive a greater share of revenue from fossil fuel-dependent business than from methane capture. We further exclude companies that only capture methane from less than 50% of the landfill sites they operate. And as always, we take out penny stocks whose share prices were lower than $0.50 in our last update. 

This means that the Climate Index includes all of the methane digester companies that are at the forefront of reducing methane emissions from waste.

If you are a Carbon Collective member, you own all of these companies through the Climate Index.