Biochar Was a Billion-Ton Dream, the Reality Is More Complicated

Picture turning yard waste, wood scraps, and farm leftovers into something that stores carbon underground for centuries and improves soil health. That’s the idea behind biochar. While this is true, it doesn’t tell the full story.

For over twenty years, researchers, entrepreneurs, and climate advocates have promoted biochar as a top way to remove carbon dioxide from the air. Early estimates said it could take out 3.4 to 6.3 billion tons of CO₂ each year, which is huge. This excitement led to many scientific papers...