How can storing plants in the sea remove carbon?

One of nature’s ways to remove CO2 from the carbon cycle is by transporting plants through rivers and into the depths of the sea. Since the carbon in plants comes from CO2 in the air (via photosynthesis), plants which accumulate on the seabed form deep reservoirs of organic carbon. This is nature’s way of creating fossil fuels. Rewind mimics and accelerates this process by collecting agriculture & forestry residues and transporting them to the deep Black Sea, effectively removing CO2 for thousands of years.

What’s special about the Black Sea?

The Black Sea is already one of the largest organic carbon sinks in the world. The rivers around it deposit megatons of carbon every year, and in the anoxic bottom, the Black Sea preserves organic carbon for thousands of years. Its volume is big enough to contain all the CO2 humanity needs to remove, and its special chemistry (no oxygen, high sulfide) ensures long-term preservation and environmental safety. Lastly, the Black Sea is also located in the middle of Europe’s bread basket, allowing high availability of residue biomass within reach.

What is biomass, and what types of biomass does Rewind use?

Biomass is a broad term describing all organic materials, from trees, through food, to food waste. Rewind focuses on clean plants that have already been cut down for other uses, are not utilized in agriculture or energy sectors. Usually, these residual plants are burnt or left to decompose in the field. Such sources of organic matter include forestry residue, orchard trimmings, and other agricultural crop residues.

Is it safe to store biomass at the bottom of the Black Sea?

Organic matter deposition and sequestration is a nature-based solution. The large rivers flow to the Black Sea, transporting millions of tons of terrestrial organic matter to the deep bottom of the Black Sea, where it is stored for thousands of years while removing carbon from the atmosphere.Rewind enhances natural processes and is committed to monitoring, reporting, and verifying the organic carbon and ecosystem continuously.

Is it energy intensive to transport biomass to the Black Sea?

Not at all. Based on previous studies and our life cycle assessment calculation, the total transportation energy consumption of biomass to the bottom of the Black Sea is less than 3% of the carbon we fix.

How much can Rewind scale carbon removal?

The Black Sea is surrounded by six countries with fertile land, forests, and agriculture, with millions of tons of biomass residue every year. These conditions allow for an abundant supply of organic matter with low or no commercial value. We aim to tenfold our carbon removal every year, reaching a gigaton scale by 2030.

Is there supporting scientific research for your method?

Several studies have examined the decomposition rate of terrestrial biomass on the seabed, along with studies of wooden shipwrecks preserved at the bottom of the Black Sea for over 2,000 years and how terrestrial biomass is deposited in sediments by rivers and preserved over geological time. Rewind's team also conducts scientific experiments and collaborates with global scientific leaders to ensure that science is solidified.