Charm collects biomass wastes and residues, such as leftover corn stalks, and heats them to high temperatures in a low-oxygen environment. The process, called pyrolysis, breaks down the biomass into three products: syngas, biochar, and carbon-rich bio-oil. The resulting syngas is used to power the pyrolyzers.

The biochar can be returned to fields to replace nutrients and improve soil health. The bio-oil, which retains much of the carbon present in the original biomass, is injected into EPA-regulated wells, where it sinks and solidifies in place, becoming permanent carbon removal.