How Renewable Natural Gas Achieves Carbon Neutrality Using CO2 as an Ingredient

When describing our process at Rebel Fuels—converting waste carbon dioxide into renewable natural gas—people often ask: "How can the end product be carbon neutral if you're using CO2 as an ingredient?" The answer lies in understanding the difference between biogenic carbon and fossil carbon.

The Biogenic Carbon Cycle: Nature's Circular Economy

The carbon in our renewable natural gas comes from biogenic sources—such as the carbon dioxide naturally produced during fermentation at an ethanol facility. This CO2 originates from corn plants that sequestered carbon in their tissues as they grow. When these plants are processed through fermentation, they release the same carbon they recently captured.

This natural cycling of carbon—from atmosphere to plants and back again—is fundamentally different from fossil fuels, which release carbon that has been locked underground for millions of years. Our process simply intercepts biogenic carbon that would be released anyway and gives it a second useful life before it returns to the atmosphere.

Carbon Accounting: No Net Increase

The carbon neutrality of our approach comes from this crucial distinction:

1. Biogenic carbon cycling: We use carbon that plants recently pulled from the atmosphere—carbon that is already part of the active, natural carbon cycle.

2. No new carbon introduction: Unlike fossil fuels, which add previously sequestered carbon to the atmosphere, our process doesn't increase the total amount of carbon in circulation.

3. Displacement effect: Every unit of our renewable natural gas used replaces fossil natural gas that would have added new carbon (as well as methane, a more potent greenhouse gas, that escapes during gathering and processing, but this is the subject for another post) to the atmosphere.

Beyond Just Carbon: Additional Environmental Benefits

Using waste CO2 from industrial processes like ethanol production creates environmental benefits beyond carbon neutrality. It prevents the need for additional natural gas extraction, reduces methane leakage from traditional gas infrastructure, and provides a sustainable solution for hard-to-decarbonize industrial heat and process applications.

Looking Forward: Scaling Climate Solutions

By harnessing the biogenic carbon cycle and giving waste carbon a second useful life, we're creating practical solutions that help industries reduce emissions while maintaining operational efficiency. By utilizing waste carbon streams that would otherwise enter the atmosphere, we're developing energy systems that are both environmentally sound and economically viable.