Benefits for composting activities and agriculture

Biochar suppresses the emission of odors from compost, especially ammonia, and makes composting much more forgiving.
Biochar matures in the compost by adsorbing a functional coating from compost which give it much greater water holding capacity and nutrient exchange capacity, behaving like permanent compost, since biochar itself is extremely long-lived in the soil.
Biochar stimulates the production of plant exudates and fungal mycelia which increases the soil aggregate stability, making the soil more resilient, more water permeable, and resistant to compaction.
Biochar captures and retains a tremendous amount of water soluble nitrates which would otherwise be lost during composting, and stimulates plant growth by providing the plant access to abundant nitrogen.
Plants exhibit a stronger immune response against pathogens due to the support and soil services of the soil microbiome fostered by co-composted biochar.
The enhanced nutrient exchange capacity afforded by co-composted biochar reduces the loss of water soluble nutrients, reducing the pressure to use fertilizer. Any fertilizer that is applied ends up being used more efficiently.

Benefits for the environment

BECCS—Bioenergy with carbon capture and sequestration, and PyCCS—pyrolysis carbon capture and sequestration, are scientifically recognized methods for drawing down carbon dioxide from the atmosphere and storing it in the soil for the long term, leveraging plants to capture carbon dioxide, which is already happening worldwide.
Nitrous oxide and methane emissions can be reduced by up to 90% in the compost pile with the addition of biochar. (Nitrous oxide, N2O, is 300x more potent than CO2, and methane is about 80-100x worse than CO2 in the first 20 years after it is emitted.)
Biochar continues to abate nitrous oxide emissions from the soil.
Biochar binds and immobilizes many pollutants, including pesticides and heavy metals, making it a useful tool for remediating contaminated soils.r
The production of biochar in the course of gasification prevents particulate matter from being released into the atmosphere compared to open combustion.
The production of biochar in the course of gasification for power generation and heating offsets fossil fuel use.