What We Do

Captura offers a critical tool in the fight against climate change utilizing unique
gigaton-scalable Direct Ocean Capture (DOC) technology developed at Caltech.

About Captura

Founded in 2021 utilizing technology developed in Caltech’s laboratories, Captura provides low-cost atmospheric carbon removal by leveraging the world’s largest natural CO2 absorber – the ocean. With minimal impacts on the environment and using only renewable electricity and seawater as inputs, our patented electrodialysis process generates a stream of measurable CO2 that can then be permanently and safely stored or utilized to make low-carbon products. 

The clip below shows our first pilot system launch just off the coast of Newport Beach, CA.

The Captura Process

Captura’s DOC technology features a flow of seawater passing through the plant, which is treated to remove its CO2 content and then returned into the ocean. This decarbonized water sits in the top layer of the ocean and will then react with the atmosphere to draw down an equivalent quantity of CO2.

In this way, Captura utilizes the ocean’s natural ability to draw down CO2 from the atmosphere. Without Captura’s technology, this well-known effect causes an increase in ocean acidification, as the ocean absorbs ~30% of the world’s emissions. By removing CO2 from the ocean, Captura’s technology benefits from the ocean’s CO2 absorption capability without increasing ocean acidification.

The Captura process begins by pulling a stream of filtered seawater into our system. Less than 1% of this is pre-treated and converted into softened seawater or brine.

This pre-treated water is then processed in Captura’s proprietary electrodialysis technology that uses renewable energy to split water molecules into an acid and base. The acid is then added to the original flow of seawater in the plant, triggering a chemical process that draws the CO2 out. We accelerate this process using a gas-liquid contactor and vacuum pump. The CO2 is captured as a measurable stream, ready for subsequent storage or utilization.

This leaves a flow of acidic, CO2-depleted seawater in the system. The base we created is then introduced to neutralize the acidity, after which the seawater is returned to the ocean to draw down more atmospheric CO2.

In summary, Captura’s process uses just renewable electricity and seawater as inputs to remove CO2 from the atmosphere. It creates no by-products and adds nothing new to the ocean. It simply removes CO2 that the atmosphere then replaces.

Why Captura?

Captura is able to deliver low-cost carbon removal through the following unique features:

Low capital costs

  • Utilizing the ocean’s natural processes to remove atmospheric CO2 reduces capital costs significantly
  • Captura’s system can reuse existing ocean-based infrastructure for deployment, such as desalination plants

Low operating costs 

  • Volumetrically, CO2 is 150x more concentrated in the ocean compared to air, making DOC an efficient way to remove atmospheric CO2
  • The process avoids the cost of making absorbents, and then regenerating or disposing of them
  • Captura’s system can leverage off-peak renewable energy pricing for the majority of the system’s energy requirements
  • The process creates no by-products that need to be disposed of at large scale


  • The technology requires no precious or rare-earth elements 
  • With the ocean covering ~70% of the world’s surface, Captura systems have the potential to be widely deployed

Storage & utilization 

  • Captura produces a measurable stream of CO2 gas that can be permanently stored for high quality carbon credits 
  • Alternatively, the CO2 stream can be used to make low-carbon products, such as sustainable aviation fuel

Deployment Strategy

Captura’s technology was developed and first demonstrated in laboratories at Caltech with imported seawater. This allowed the Captura team to measure and optimize system performance in advance of an ocean-based pilot. 

In the summer of 2022, Captura installed our first ocean-based, stand-alone pilot facility in Newport Beach, CA. That pilot system is capable of capturing one ton of CO2 per year. The use of a continuous flow of seawater allows our team to measure system performance and implement system improvements.  

Captura has also built its next-generation system which has 100x the capacity of the first. The new, larger system has been successfully operating end-to-end in the company’s lab in Pasadena and Captura plans to move it to AltaSea at the Port of Los Angeles in the summer of 2023 to begin ocean field trials. 

As more corporations seek out strategies for achieving Net Zero, the demand for carbon removal is expected to grow. Captura’s technology is highly scalable, and to facilitate rapid and widespread global deployment we intend to work with partners who will license our technology and build Captura carbon removal plants throughout the world. 

We expect our first commercial facilities to be co-located with existing ocean-based infrastructure, either onshore or offshore. Longer-term, we envisage dedicated, standalone Captura platforms similar to today’s ocean-based energy infrastructure. 

Combining the inherent scalability of Captura’s process with this licensing model allows us to deliver on our mission of providing a globally scalable tool for climate action.