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Version published: 
November 28, 2023 - 10:16am
November 28, 2023 - 10:16am November 16, 2023 - 5:30pm November 13, 2023 - 1:01pm

Projects from Ocean CDR Community

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Examples of Mangrove Forest Restoration Efforts
Version published: 
November 28, 2023 - 10:18am
November 28, 2023 - 10:18am November 28, 2023 - 10:17am November 22, 2023 - 10:30am November 20, 2023 - 12:28pm November 16, 2023 - 2:57pm November 13, 2023 - 1:02pm November 13, 2023 - 10:37am November 10, 2023 - 2:33pm
Microalgae cultivation for carbon dioxide removal (CDR) is emerging as a potential solution to the climate crisis. Microalgae are fast-growing organisms that convert carbon dioxide (CO2) into biomass and various other organic compounds through photosynthesis. Microalgae play a critical role in the global carbon cycle, capable of fixing CO2 10 - 50 times more efficiently than terrestrial plants . Proposed strategies to utilize microalgae for carbon dioxide removal take advantage of the physiology of microalgae and their role in the carbon cycle and seek to achieve long term (>100 years) sequestration and storage of carbon. The two primary strategies for microalgae CDR are:
  1. Open systems where the open ocean is directly manipulated to enhance biological production, capture atmospheric CO2, and export the captured carbon to the deep ocean. In open systems, CO2 fixation is facilitated by the addition of limiting macronutrients (e.g., phosphorus, nitrogen, silica) and/or micronutrients (e.g., iron) to the ocean’s surface to augment biological production . Open system techniques accelerate natural processes already occurring in the ocean. Most approaches in the open ocean fall into the following two categories (some proposals that do not fit into these categories are also explored).
    1. Surface nutrient addition: the direct addition of nutrients (macro or micro) into ocean waters in situ to increase microalgal growth 
    2. Nutrient upwelling: artificial upwelling of nutrient-rich deep ocean waters to the surface to increase microalgal growth
  2. Closed systems where inputs and growth conditions are controlled, and outputs (microalgae) are harvested within the confines of a pond or a photobioreactor. In closed systems, CO2 fixation is facilitated by the mixing of required inputs (sunlight, nutrients, CO2, water) and the introduction of microalgae culture with the intention of reproduction and continuous fixation in a contained system . This can be accomplished on shore in cultivation ponds or photobioreactors, or afloat in photobioreactors either stationary or towed at sea .
    1. Onshore: encompasses more established methods of microalgae cultivation, including photobioreactors, cultivation ponds, and hybrid onshore configurations. In these systems, all inputs are tightly controlled and regulated, and outputs must be directly managed through either storage or utilization of byproducts. While cultivation techniques are well-established and show high technological readiness, storage and utilization pathways remain underdeveloped and scale is a major consideration. Social and environmental risks for closed onshore systems are easier to monitor and mitigate due to the controlled nature of the system. 
    2. Offshore: includes floating photobioreactors (PBRs) that are incorporated into a floating platform which can be stationary or towed behind a ship. In these systems, cultivation occurs in the photobioreactor, inputs are regulated, and outputs can be actively managed or directed. While at sea, these photobioreactors operate much like their onshore counterparts to cultivate microalgae, however nutrients and energy are provided by the ocean water and wave action, respectively. After microalgae are cultivated, they can be sunk into the deep ocean for sequestration or hauled to shore to be used as biomass. This is an area that has garnered much attention in startup communities (see this Y Combinator request for startups), however, little is available about the technologies in the open-sourced or peer reviewed literature.
 

     
Microalgae cultivation for carbon dioxide removal (CDR) is emerging as a potential solution to the climate crisis. Microalgae are fast-growing organisms that convert carbon dioxide (CO2) into biomass and various other organic compounds through photosynthesis. Microalgae play a critical role in the global carbon cycle, capable of fixing CO2 10 - 50 times more efficiently than terrestrial plants . Proposed strategies to utilize microalgae for carbon dioxide removal take advantage of the physiology of microalgae and their role in the carbon cycle and seek to achieve long term (>100 years) sequestration and storage of carbon. The two primary strategies for microalgae CDR are:
  1. Open systems where the open ocean is directly manipulated to enhance biological production, capture atmospheric CO2, and export the captured carbon to the deep ocean. In open systems, CO2 fixation is facilitated by the addition of limiting macronutrients (e.g., phosphorus, nitrogen, silica) and/or micronutrients (e.g., iron) to the ocean’s surface to augment biological production . Open system techniques accelerate natural processes already occurring in the ocean. Most approaches in the open ocean fall into the following two categories (some proposals that do not fit into these categories are also explored).
    1. Surface nutrient addition: the direct addition of nutrients (macro or micro) into ocean waters in situ to increase microalgal growth 
    2. Nutrient upwelling: artificial upwelling of nutrient-rich deep ocean waters to the surface to increase microalgal growth
  2. Closed systems where inputs and growth conditions are controlled, and outputs (microalgae) are harvested within the confines of a pond or a photobioreactor. In closed systems, CO2 fixation is facilitated by the mixing of required inputs (sunlight, nutrients, CO2, water) and the introduction of microalgae culture with the intention of reproduction and continuous fixation in a contained system . This can be accomplished on shore in cultivation ponds or photobioreactors, or afloat in photobioreactors either stationary or towed at sea .
    1. Onshore: encompasses more established methods of microalgae cultivation, including photobioreactors, cultivation ponds, and hybrid onshore configurations. In these systems, all inputs are tightly controlled and regulated, and outputs must be directly managed through either storage or utilization of byproducts. While cultivation techniques are well-established and show high technological readiness, storage and utilization pathways remain underdeveloped and scale is a major consideration. Social and environmental risks for closed onshore systems are easier to monitor and mitigate due to the controlled nature of the system. 
    2. Offshore: includes floating photobioreactors (PBRs) that are incorporated into a floating platform which can be stationary or towed behind a ship. In these systems, cultivation occurs in the photobioreactor, inputs are regulated, and outputs can be actively managed or directed. While at sea, these photobioreactors operate much like their onshore counterparts to cultivate microalgae, however nutrients and energy are provided by the ocean water and wave action, respectively. After microalgae are cultivated, they can be sunk into the deep ocean for sequestration or hauled to shore to be used as biomass. This is an area that has garnered much attention in startup communities (see this Y Combinator request for startups), however, little is available about the technologies in the open-sourced or peer reviewed literature.
 

     

Projects from Ocean CDR Community

No projects listed. Want to add a project to this section? Become a Contributor.
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Examples of Seagrass Restoration Efforts
Version published: 
November 28, 2023 - 10:19am
November 28, 2023 - 10:19am November 22, 2023 - 10:30am November 20, 2023 - 12:28pm November 16, 2023 - 2:58pm November 13, 2023 - 2:48pm November 13, 2023 - 1:03pm

Projects from Ocean CDR Community

No projects listed. Want to add a project to this section? Become a Contributor.
Read More

Examples of Salt Marsh Restoration Efforts
Version published: 
November 28, 2023 - 11:33pm
November 28, 2023 - 11:33pm November 28, 2023 - 10:20am November 22, 2023 - 10:30am November 20, 2023 - 12:30pm November 16, 2023 - 2:58pm November 13, 2023 - 1:03pm November 13, 2023 - 10:39am November 13, 2023 - 10:38am
Microalgae cultivation for carbon dioxide removal (CDR) is emerging as a potential solution to the climate crisis. Microalgae are fast-growing organisms that convert carbon dioxide (CO2) into biomass and various other organic compounds through photosynthesis. Microalgae play a critical role in the global carbon cycle, capable of fixing CO2 10 - 50 times more efficiently than terrestrial plants . Proposed strategies to utilize microalgae for carbon dioxide removal take advantage of the physiology of microalgae and their role in the carbon cycle and seek to achieve long term (>100 years) sequestration and storage of carbon. The two primary strategies for microalgae CDR are:
  1. Open systems where the open ocean is directly manipulated to enhance biological production, capture atmospheric CO2, and export the captured carbon to the deep ocean. In open systems, CO2 fixation is facilitated by the addition of limiting macronutrients (e.g., phosphorus, nitrogen, silica) and/or micronutrients (e.g., iron) to the ocean’s surface to augment biological production . Open system techniques accelerate natural processes already occurring in the ocean. Most approaches in the open ocean fall into the following two categories (some proposals that do not fit into these categories are also explored).
    1. Surface nutrient addition: the direct addition of nutrients (macro or micro) into ocean waters in situ to increase microalgal growth 
    2. Nutrient upwelling: artificial upwelling of nutrient-rich deep ocean waters to the surface to increase microalgal growth
  2. Closed systems where inputs and growth conditions are controlled, and outputs (microalgae) are harvested within the confines of a pond or a photobioreactor. In closed systems, CO2 fixation is facilitated by the mixing of required inputs (sunlight, nutrients, CO2, water) and the introduction of microalgae culture with the intention of reproduction and continuous fixation in a contained system . This can be accomplished on shore in cultivation ponds or photobioreactors, or afloat in photobioreactors either stationary or towed at sea .
    1. Onshore: encompasses more established methods of microalgae cultivation, including photobioreactors, cultivation ponds, and hybrid onshore configurations. In these systems, all inputs are tightly controlled and regulated, and outputs must be directly managed through either storage or utilization of byproducts. While cultivation techniques are well-established and show high technological readiness, storage and utilization pathways remain underdeveloped and scale is a major consideration. Social and environmental risks for closed onshore systems are easier to monitor and mitigate due to the controlled nature of the system. 
    2. Offshore: includes floating photobioreactors (PBRs) that are incorporated into a floating platform which can be stationary or towed behind a ship. In these systems, cultivation occurs in the photobioreactor, inputs are regulated, and outputs can be actively managed or directed. While at sea, these photobioreactors operate much like their onshore counterparts to cultivate microalgae, however nutrients and energy are provided by the ocean water and wave action, respectively. After microalgae are cultivated, they can be sunk into the deep ocean for sequestration or hauled to shore to be used as biomass. This is an area that has garnered much attention in startup communities (see this Y Combinator request for startups), however, little is available about the technologies in the open-sourced or peer reviewed literature.
 

     
Microalgae cultivation for carbon dioxide removal (CDR) is emerging as a potential solution to the climate crisis. Microalgae are fast-growing organisms that convert carbon dioxide (CO2) into biomass and various other organic compounds through photosynthesis. Microalgae play a critical role in the global carbon cycle, capable of fixing CO2 10 - 50 times more efficiently than terrestrial plants . Proposed strategies to utilize microalgae for carbon dioxide removal take advantage of the physiology of microalgae and their role in the carbon cycle and seek to achieve long term (>100 years) sequestration and storage of carbon. The two primary strategies for microalgae CDR are:
  1. Open systems where the open ocean is directly manipulated to enhance biological production, capture atmospheric CO2, and export the captured carbon to the deep ocean. In open systems, CO2 fixation is facilitated by the addition of limiting macronutrients (e.g., phosphorus, nitrogen, silica) and/or micronutrients (e.g., iron) to the ocean’s surface to augment biological production . Open system techniques accelerate natural processes already occurring in the ocean. Most approaches in the open ocean fall into the following two categories (some proposals that do not fit into these categories are also explored).
    1. Surface nutrient addition: the direct addition of nutrients (macro or micro) into ocean waters in situ to increase microalgal growth 
    2. Nutrient upwelling: artificial upwelling of nutrient-rich deep ocean waters to the surface to increase microalgal growth
  2. Closed systems where inputs and growth conditions are controlled, and outputs (microalgae) are harvested within the confines of a pond or a photobioreactor. In closed systems, CO2 fixation is facilitated by the mixing of required inputs (sunlight, nutrients, CO2, water) and the introduction of microalgae culture with the intention of reproduction and continuous fixation in a contained system . This can be accomplished on shore in cultivation ponds or photobioreactors, or afloat in photobioreactors either stationary or towed at sea .
    1. Onshore: encompasses more established methods of microalgae cultivation, including photobioreactors, cultivation ponds, and hybrid onshore configurations. In these systems, all inputs are tightly controlled and regulated, and outputs must be directly managed through either storage or utilization of byproducts. While cultivation techniques are well-established and show high technological readiness, storage and utilization pathways remain underdeveloped and scale is a major consideration. Social and environmental risks for closed onshore systems are easier to monitor and mitigate due to the controlled nature of the system. 
    2. Offshore: includes floating photobioreactors (PBRs) that are incorporated into a floating platform which can be stationary or towed behind a ship. In these systems, cultivation occurs in the photobioreactor, inputs are regulated, and outputs can be actively managed or directed. While at sea, these photobioreactors operate much like their onshore counterparts to cultivate microalgae, however nutrients and energy are provided by the ocean water and wave action, respectively. After microalgae are cultivated, they can be sunk into the deep ocean for sequestration or hauled to shore to be used as biomass. This is an area that has garnered much attention in startup communities (see this Y Combinator request for startups), however, little is available about the technologies in the open-sourced or peer reviewed literature.
 

     

Projects from Ocean CDR Community

No projects listed. Want to add a project to this section? Become a Contributor.
Read More
Help advance Ocean-based CDR road maps. Submit Comments or Content
Suggested Citation:
Ocean Visions. (2024) Ocean-Based Carbon Dioxide Removal: Road Maps. https://www2.oceanvisions.org/roadmaps/ remove/mcdr/ Accessed [insert date].
Change Road Map
Electrochemical
 CDR
Macroalgae Cultivation and Carbon Sequestration
Ocean Alkalinity Enhancement
Microalgae Cultivation and Carbon Sequestration
Blue Carbon Restoration and Carbon Sequestration
Engaging Key Audiences
Expanding Finance and Investment

Blue Carbon Restoration and Carbon Sequestration

Introduction
Coastal Vegetated Ecosystems
Seaweed
Animal Carbon
Governance & Policy
Additional Resources
Help advance Ocean-based CDR road maps. Submit Comments or Content
Suggested Citation:
Ocean Visions. (2024) Ocean-Based Carbon Dioxide Removal: Road Maps. https://www2.oceanvisions.org/roadmaps/ remove/mcdr/ Accessed [insert date].

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