Back to all projects


Turning Sargassum into biochar for soil applications

What started out as a native Atlantic seaweed has since manifested into a widespread Caribbean nuisance – overwhelming beaches and having to be cleared before ending up in landfills. By turning readily available Sargassum into biochar, we ensure carbon is permanently locked away, while preserving sensitive nearshore ecosystems and local community functioning in the Dominican Republic.

  • 4 generations carbon sink
  • Soil enhancing product applications
  • Coastal ecosystem health and marine biodiversity
  • Simultaneous methane avoidance

Status of production: Under development


One ton of carbon negative Blue Biochar from Sargassum removes 1.9 tons of CO2 from the atmosphere into a stable solid form.

Large scale problems require ambitious solutions. With regions in the Dominican Republic experiencing influxes of 30 tons of Sargassum per kilometer of coastline, Sinkit is working towards processing collected Sargassum into biochar for local soil applications. Throughout the 6-month influx season, Sinkit hopes to utilize over 4200 tons of Sargassum to produce 2000 tons of Blue Biochar.

Our biochar creates both economic and ecological value from an otherwise discarded biomass. On one hand, we turn waste into a valuable agricultural product with incredible soil enhancing properties. On the other, we also turn Sargassum from a carbon source into a carbon sink. By using Sargassum that would have otherwise decomposed, we avoid methane from being emitted into the atmosphere while simultaneously preventing hypoxia in waters vital to the functioning of carbon rich ecosystems including mangroves, seagrass beds, and coral reefs.

Biochar derived from seaweed has unique properties that make it especially interesting for soil applications. It has a very high cation exchange capacity making it an excellent substrate for nutrient exchange and uptake in plants. It’s also a great buffer for soil pH, and only has to be applied once for continuous improvements!

  • Example of usage

  • Co-benefits

  • Economic acceleration impact

  • Audit information

Join our mission

Sinkit is a cooperative organization, which means everyone with a shared vision and mission can become a member and invest in Sinkit projects. Want to join us?