Our best Ally for climate

Carbon Removal through Ocean Alkalinity Enhancement

High-quality carbon removal with a permanent ocean-based solution

Encouraging the Ocean Alkalinity Enhancement (OAE) represents an innovative strategy in the fight against climate change. Increasing ocean alkalinity strengthens the ocean's capacity to absorb and sequester atmospheric CO₂, over long cycles of more than 20,000 years.

High Sustainability

20,000+ years

The ocean sequesters atmospheric CO₂ in the form of dissolved inorganic carbon (DIC) over the long term.

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Not Volatile

0 risk of reversibility

The CO₂ is sequestered in deep layers with no contact with the atmosphere. Storage in the ocean is without risk of reversibility.

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High Scalability

Megatones of CO₂

In theory, OAE can be deployed on a large scale worldwide, depending on feasibility, availability and local conditions.

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Serious Third-Party

Science based expertise

We strictly follow the scientific recommendations of public scientists, and let them guide the development of the MRV (Measurement, Reporting and Verification) process.

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We engage with marine industries for advancing ocean-based strategies

We are exploring synergies with existing marine infrastructures to advance our ocean-based climate strategies. We focus on identifying deployment sites that fit our mission, particularly activities that require access to the sea. Leveraging these pre-existing operations not only mitigates negative externalities, but also delivers tangible impacts more quickly.

Water Management

  • Desalination Plants: Extracting freshwater from seawater
  • Adjacent Sites: Permitted seawater intake and discharge


  • Oyster farm: Floating structures accumulate organic matter
  • Shellfish nurseries: Beneficial for suitable enhanced bioturbation

Artificial & Natural

  • Artificial Islands: Potential deployment of artificial sites
  • Coastal Protection: High erosion dynamics


  • Dredged Sites : Potential sites post-activity completion
  • Aggregates Mining : Potential sites post-activity completion

What is Ocean Alkalinity Enhancement ?

Ocean Alkalinity Enhancement involves artificially increasing the alkalinity of seawater. This is typically done by adding alkaline materials to the ocean. The added alkalinity enhances the ocean's capacity to absorb and store more CO₂ from the atmosphere.

Ocean Alkalinity Enhancement (OAE) is a nature-inspired method that helps reduce CO₂ levels in the atmosphere. The process involves adding alkalinity to the ocean, activating a series of natural reactions that transform dissolved CO2 into stable bicarbonate and carbonate molecules. This transformation removes CO₂ from the atmosphere, enabling the ocean to absorb more CO₂.

Inspired by geological processes that capture carbon over millennia, OAE accelerates this phenomenon, achieving results in a matter of months to years, depending on the alkaline materials or technologies chosen.

By introducing an antacid-like substance into seawater, the process neutralizes excess CO₂ and mitigates harmful ocean acidity. Some materials are abundant and have already been used in water treatment for decades.

There are several ways of adding alkalinity to the ocean. These include spreading finely ground alkaline substances in the open sea, depositing alkaline sand or gravel on beaches or coastal seabeds, or reacting seawater with alkaline minerals inside specialized fuel cells before discharging it into the ocean.

How to generate alkalinity ?

We have conducted extensive research into various methods of creating alkalinization, each with its advantages and disadvantages. Our priority is to select best approaches that have a positive impact on marine life and are effective for ocean carbon capture.

Our first focus was on alkalinization by rock weathering, and more specifically on olivine material.

Natural Rock Weathering

We harness the power of nature by using minerals such as olivine to reduce ocean acidity and stimulate marine ecosystems. This energy-efficient method focuses on enhancing carbon capture using materials such as carbonates and silicates, but over longer periods due to natural processes.

Electrochemical Approaches

Fast and innovative, electrochemical solutions are designed to reduce the implementation time of existing technologies. Although more energy-intensive, they can be used in synergy and compatibility with existing coastal industries such as desalination or water treatment plants.

Biological Methods

By integrating shellfish into carbon removal efforts, we can create sustainable cycles in marine environments. This emerging new approach not only supports ocean alkalinization, but could also enrich shellfish farming locally, aligning with natural ecosystems for mutual benefit.

Coastal Natural Preservation

Natural ecosystems create alkalinization; preserving and restoring them is a holistic strategy we promote, aimed at supporting carbon removal efforts while safeguarding fragile coastal ecosystems. Ecosystems such as mangroves, seagrass beds and salt marshes are essential to our approach.

Join our strong and pioneering partners to move things forward together

They trust Carbon Time to advance scientific research on Ocean Alkalinity Enhancement. Together we want to guarantee rigorous analysis and credibility of those climate solution, evaluated through public scientists.

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Backed by a global
scale movement

Team for the Planet is a global scale movement of thousands of citizens and companies. We are proud to have been financed by the movement and created the first innovation. Team for the Planet is a non-profit company dedicated to raising 1 billion euros to fund 100 innovative compagnies fighting climate change.

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