Technical Questions:
1.1 How much seaweed is produced per Marine Permaculture array (MP) per year?Different seaweed species have different harvesting cycles and biomass production. While red seaweed species are smaller than kelp, they are harvested more often (every six weeks). Kelp grows bigger, but is only harvested every three months. Both are capable of peak growth rates of 5-15% per day, under replete conditions. A square kilometer MP (100 hectares) can grow up to 3,500 dry tons of seaweed per year under optimal conditions.
1.2 Why is irrigation of seaweeds important?Irrigation in MP arrays enables replete macronutrients to be provided to the seaweeds. In subtropical locations, where replete light is available year-round, irrigation enables four growing seasons for kelp and up to eight growing seasons for some red seaweeds. Most regions of the world may not have replete nutrients year-round, thus irrigation during the “dry season” (low productivity) with deeper water enables replete growth rates to be maintained. Irrigation also improves the consistency of crops from one harvest to another, and enables thermal management of the seaweeds. It keeps the farm running at 100% capacity factor. Organisms in the ocean mostly rely on the ocean ambient temperature and do not thermally regulate. Peak sea surface temperature anomalies of 2 degrees is analogous to a human body experiencing a fever of 2 degrees. It has a big effect on performance and metabolism. Controlled irrigation enables MP to control temperatures in the seaweed forest. Our organisation was the first to show that irrigation with deep water can reverse coral bleaching in the field and reduce some effects of global warming on marine organisms. We have started with the MP seaweed forests to showcase this capability.
1.3 How does irrigation work?We use on-site solar, wind, thermal or wave energy to bring cooler water up to the mixed layer and bring it into thermal equilibrium with the surface water. Then we pass the cooler water through perforated diffuser pipes that irrigate the attached seaweed forest, supplying nutrients to the seaweed for growth.
1.4 Why is it important to irrigate the seaweed?With global warming, overturning circulation is reduced in subtropical and tropical oceans. As a result, those oceans stably stratify, decimating nutrient levels. Without nutrients, seaweed growth halts, seaweed becomes sickly and it starts to die. Irrigating the seaweed with deeper, cooler water provides nutrients and keeps the seaweed cooler in its target temperature range. This irrigation results in replete conditions for the seaweed to grow, resulting in higher fluxes per hectare and higher yields.
1.5 How do you ensure buoyancy for the cooler water being brought up?We have established a patent-pending buoyancy condition for the cooler water that applies to over half of the subtropical oceans. A heat exchanger with 2 degrees °C approach temperature can establish buoyancy for cooler water that has a salinity 1 part-per-thousand lower than the mixed layer. For the first time, we have established buoyancy criteria for efficient use of upwelled nutrients. Before this discovery, deep water was used to grow kelp, but most of it sank back to the thermocline. With Marine Permaculture, nearly all of the upwelled water grows algae, with over 90% phosphate utilization.
1.6 Does MP seaweed grow faster than naturally occurring seaweed forests?Yes, by understanding the ocean environment and the environmental variables most affecting growth, we expect MPs will enjoy higher yields than in the wild by providing consistent, year-round irrigation, whereas natural kelp forests may experience replete nutrients but may not have replete light in the winter and may be nutrient-limited during the warm summer months, when nutrient levels can be lower. Also, natural kelp forests tend to grow in high latitudes for thermal reasons and thus may be light-limited all winter, whereas Marine Permaculture forests can be grown in subtropical latitudes and get replete light four seasons per year and replete nutrients four seasons per year.
1.7 How much carbon can be sequestered as an ancillary benefit with MPs? Each 100-hectare MP array in subtropical oceans has the potential to draw down 2,500-6,000 tons of carbon dioxide per year from the atmosphere and associated surface ocean waters. At an average of 1 ton CO2e per ton of seaweed, and 50 tons (dry weight) of seaweed per hectare, each hectare can fix an average of 50 tons of CO2e per year.
Research has confirmed that carbon fixation in kelp forests can exceed the carbon fixation per hectare of terrestrial forests, partly because terrestrial plants typically photosynthesize at 0.2-2% efficiency, whereas ocean seaweed efficiency can exceed 8%. With far more open ocean available to us than the available area for old-growth tropical rainforest, the Marine Permaculture approach has distinct advantages of scalability.
1.8 How are we sure this is carbon negative and not just cycling carbon in a loop?We know the MP process is carbon negative by analysing the Redfield ratio for seawater, plankton and seaweed. “The Redfield ratio or Redfield stoichiometry is the atomic ratio of carbon, nitrogen and phosphorus found in phytoplankton and throughout the deep oceans. This empirically developed stoichiometric ratio was originally found to be C:N:P = 106:16:1 (and has more recently been revised to 117:14:1).” However, for seaweeds the C:P redfield ratio can range from 220:1 to 800:1.
We have developed a rigorous methodology for tracking carbon in the ocean. To measure the carbon, we track the phosphorus. That is because the phosphorus, unlike nitrogen and carbon, does not transfer to the air to any significant degree. Thus, in the pelagic ocean, it serves as a reference for tracking the carbon being used. Ultimately, over 90% of the phosphorus will be used by the seaweed. For every atom of phosphorus used 220-800 carbon atoms are used for seaweed growth. This means that for every carbon atom upwelled at least twice as many carbon atoms can be sunk to the bottom of the ocean.
If particulate or dissolved organic carbon is kept at the bottom of the sea for centuries, even if oxidized, it can contribute to long-term C stocks as determined by the UN CDM. The seaweed processed at sea, sinks hundreds of meters per day to the bottom of the sea. In a few days it reaches the seafloor, mostly still intact. In some locations the deep water is anoxic, so the carbon will remain in under-oxidized form for millennia. In other regions, the carbohydrate of the seaweed will be eventually respired and oxidized. There is over 1,000 times more oxygen in the deep ocean than is required to fully oxidize 1,000 gigatons of carbohydrate (carbon) from seaweed. Said another way, if all 1,000 gigatons of carbohydrate (carbon) were oxidized and distributed in the deep ocean, it would only decrease the oxygen level by 0.1%. This deep carbon also remains underwater for millennia. The rule of thumb many physical oceanographers use is once the carbon is sunk >1km below the surface, the median outcropping time is 100 to 2,000 years (Dr. Raymond Schmitt, WHOI Physical Oceanographer, NAS). This timescale is valid whether through the mechanism of vertical eddy diffusion or through lateral advection to western boundary currents. All of Marine Permaculture seaweed residual carbon can be sequestered to depths of more than 1 km in a matter of a couple of days at normal sink rates.
The United Nations grants a carbon credit, if the methodology supports a sequestration time of 100 years or longer. Some of our anticipated deployment sites are among the largest anoxic basins in the world. In these sites, kelp forest Blue Carbon sinks remain on the seafloor for millennia.
1.9 Can you describe core design details of an MP array?Marine Permaculture uses renewable energy to lift colder, denser water bearing nutrients from below the “nutricline”, near the thermocline, to the nominal MP substrate depth of <25m. Wave, solar or ocean thermal power can be sufficient to restore circulation. Under wave energy, a surface buoy connects to a low-stretch, ¼” steel cable going 30-40 meters deep to a flapper valve pump that channels the cool, nutrient-rich water through a flexible, curved high-density polyethylene (HDPE) pipe that reaches depths of 200-400m. Before reaching the seaweed forest, this upwelled water is warmed in the heat exchanger to establish buoyancy. The water then irrigates the kelp forest through perforated diffusion pipes. Cable lengths attached to surface buoys determine the depth of the system.
In one embodiment, a self-adjusting chain system enables the depth of the Marine Permaculture to vary over time in a way consistent with maximal growth rates. HDPE pipe and welds have proven to be highly flexible and resilient in deep ocean deployments at the Natural Energy Lab, Hawaii Authority (NELHA) and other locations for over 40 years.
We also have a technology roadmap in place to develop more cost-effective technologies over the next three years to bring deep nutrient-rich water to the seaweed arrays, as currently upwelling involves several of the MP’s most costly elements. We estimate that such a system will reduce costs significantly.
1.10 Can you compare MP seaweed production to nearshore operations?Most of the world’s seaweed production occurs in coastal zones, which often have multiple, competing uses and little space to increase algae cultivation areas. Intertidal and subtidal zones are in high demand for tourism and development, but epipelagic waters are plentiful, enabling Marine Permaculture deployment and increasing productivity.
Marine Permaculture aims to restore natural upwellingand associated regional macronutrient cycling in offshore waters. This will enable replete macroalgae production in pelagic waters and increasing cultivation areas that are resilient to climate disruption. Unlike traditional mariculture, Marine Permaculture arrays are thermally stabilized with cool, deep water and can survive the greatest heat waves and El Ninos. During these periods, many traditional seaweed beds are lost due to lack of nutrients and high temperatures.
1.11 Is it possible to integrate mussel farming?Integrated mussel farms could be an option and might work best for smaller MPs, close to shore where plankton abundance is higher and advection of nutrients and plankton is slower. Mussels could offer additional income streams for fishers and pose an opportunity for carbon sequestration. However, mussels require higher plankton density than fish for optimal production. These levels are not assured yet on the open ocean, whereas the plankton levels are adequate for finfish such as sardines, anchovies, salmon and game fish. With over half a dozen revenue streams identified for Marine Permaculture with seaweed and fish, we have not focused as much on mussels. Our large-scale deployment in the open ocean will be specifically designed to produce maximum seaweed and fish yields and therefore, mussels are not planned to be part of the system at present.
1.12 Are piracy and overfishing risks?The initial sites will be in partner-managed or protected waters. Piracy and overfishing are risks in some MP locations. However, this will be mitigated by the limited visibility of MP from a distance, and by utilizing existing Marine Protected Area regulations, Admiralty Law, the Law of the Sea, strict fishing policies, remote monitoring technology, and community engagement and relations.
1.13 Are MPs safe from large ocean-going ships and storms?MPs remain at a nominal depth of up to 25 meters to eliminate risks to navigation. This depth also ensures MP resilience under hurricane conditions. Ten-meter hurricane wave swells typically break in 18 meters of water depth. Light quality and quantity (green and blue at 25 m depth) is still sufficient for seaweed and plankton growth in the open ocean.
1.14 How much maintenance is required to keep MPs functional?All components of the MP arrays are durable, with low maintenance profiles, enabling infrequent preventive maintenance intervals of months to years, once fully developed. Marine Permaculture technology will create conditions that enable seaweed to survive in the open ocean, using renewable energy and without additional fertilizer inputs or operation-intensive infrastructure such as tanks, nets, fish feed or deepwater moorings. Seaweed irrigation with nutrient rich water continues automatically and unattended with renewable energy, keeping operation and maintenance costs low. The kelp cutter will harvest each MP once per season and sustainably harvest up to 900 tonnes of kelp in one day, cropping only the top 1-2 meters of the kelp forest to keep the kelp growing at their maximum rate.
1.15 What types of seaweed will be produced? What is the difference among seaweeds?Marine Permaculture enables multiple trophic and spatial niches and increases production per unit area. Judicious selection of local native and compatible fast-growing species, e.g., Macrocystis or Ecklonia, helps to maximize yield and will be the “backbone” of our offshore Marine Permaculture. Further selection of local species depends on seedling availability and market demand. We identified species for fast growth, high-value bioproduct production and improved resiliency of fish habitat. In particular, Macrocystis can grow up to 1/2 meter per day, Eucheuma provides high-quality carrageenan and high-value nutraceuticals, and Asparagopsis provides “supreme seaweed”, for the highly valued limu kohu of Hawaii, and the reduction of enteric methane emissions from ruminant livestock. Eucheuma cottonii (Kappaphycus alvarezii) and E. spinosum (E. denticulatum) have established commercial markets today.
1.16 What are seaweeds used for?Since the 1950’s, seaweed culture has been developed and represents more than 99% of the global seaweed production today. The world production is dominated by Asian countries (99%), with China, Indonesia and Philippines as global production leaders. Seaweed products comprise food, cosmetics, feed supplements, agricultural biostimulants, pharmaceuticals, biofuels and recently fabrics. The biggest industry is the food industry in which seaweeds are directly or indirectly consumed by people as sea vegetables. The second largest industry is hydrocolloid industry, where seaweed contains carrageenan, agars and alginates used in pharmaceutical, cosmetics, textile, paint, edible food coatings, biomedical applications, microbiology, molecular biology or animal feed applications. Other additives are also extracted from seaweed and used in food, cosmetics, healthcare or agrochemistry industries. They can be used also for wastewater treatment.
1.17 How much of the MP seaweed forest do you harvest each season?In the case of a Macrocystis kelp forest, we harvest to a depth of 1.5 meters, leaving the remainder of the 25-meter depth untouched for maximal regrowth in the coming season. In the 90-day season, the kelp can grow another stipe of up to 45 meters. When the kelp reaches 25 meters it begins to grow horizontally along the surface. Thus, approximately half of the seaweed can be harvested when the kelp is harvested at 1.5m depth. This approach is intended to maximize yields while preserving ecosystem function and MP growth. Such growth is regenerative in the sense that the revenue supports increased ecosystem services, and the ecosystem responds with higher yields. The deployment location, specific local market opportunities as well as the economic needs of coastal participating communities will determine which value streams will be initially chosen. If the economic focus lies on fish, little seaweed will be harvested to produce seaweed products, leaving almost all the harvested seaweed for carbon sequestration. While harvesting most of the seaweed for food may leave less for carbon sequestration, extracting high-value products such as phycobiliproteins from seaweed, uses only 1% of the carbon, leaving over 90% of the carbon to go to Blue Carbon sinks to the middle and deep ocean.
1.18 How can MPs benefit from onshore renewable energy projects?Hotels with 5MW air conditioning load or greater, located close to the beach, can use deep seawater cooling for air conditioning in conjunction with Marine Permaculture. This integration also provides a unique opportunity to differentiate from competition and an eco-touristic advantage in having an identity that is cleaner and more environmentally friendly than alternatives. A 5MW system is enough for a few-hectare MP. Larger systems could be 100 MW or more. A 2.5m pipe is sufficient for 100 hectares or more, so the size of the array is a function of how much water is being upwelled. These arrays will also protect the corals near the resorts (the hotel reef) from thermally induced photobleaching.
1.19 What are some objections to the MP approach?Critics have argued that Marine Permaculture does not necessarily restore kelp forest, only creating one offshore in a different place. In response it is helpful to note that Marine Permaculture regenerates regional ecosystem services provided by kelp forests and other seaweed forests. Marine Permaculture provides cooler, deeper waters needed by seaweed and a feeding and breeding ground for forage fish. Through these ecosystem services we can enhance the productivity, climate resilience and survival of local kelp forests and other local ecosystems. In addition, kelp forests reduce ocean acidification, increase oxygen levels and sequester carbon far downstream from the forest locations. The ecosystem service benefits accrue regionally, including increasing oxygen levels, reduced ocean acidification, restored natural upwelling and regional carbon sequestration. The loss of upwelling in the past decades is particularly concerning. Marine Permaculture helps to restore that upwelling while obtaining a sustainable yield.
Critics may also argue that MP would displace some ecosystem offshore. However, the carbon flux of such ecosystems and the biomass density of such pelagic waters is so much lower than the kelp forest, that it is commonly called by Sir David Attenborough “the mostly empty ocean.” Using <1% of such mostly empty regions to ensure global food security, restore regional biological processes and reduce human suffering represents a responsible approach to addressing climate challenges.
Some question whether MP could contribute to harmful algal blooms. There are many factors such as reduced temperature and improved overturning circulation that actually moves the photozone away from harmful algal blooms. We plan to monitor for such blooms, improbable as they may be, as well as other environmental consequences.
Some critics have suggested that we would attract fish so strongly that they will no longer migrate. In a sense, such a development may be better than losing those species entirely. Marine Permaculture aims to produce more fish, not just have the existing fish stay at the MP. In any case, the fish are free to come and go and depart on their annual migrations at will. We can also control how many fish we harvest to ensure sustainability.
1.20 Are larger open-ocean MPs preferable?We envision MPs in the range of one to 100 hectares. The larger MPs may enjoy economies of scale, potentially increasing efficiency, but the optimal size has yet to be proven. Near shore installations compete with other area uses and will be far more bureaucratic to permit and operate. We expect that sustainable seaweed mariculture with deepwater irrigation will be in the 1-100 Ha range.
1.21 Can MPs be “moved” remotely?Multiple associated MPs enable large-scale cultivation of macroalgae in the open ocean. In the long term, self-guided arrays can use shear from mesoscale eddies for propulsion normal to current directions, providing means for navigation and guidance. These mesoscale eddies are analogous to thermals in the sky utilised by soaring birds to achieve navigational goals. The system can be guided using a remotely controlled system similar to those used by Liquid Robotics developed in Silicon Valley and used by Boeing in their DOD programs. Navigational guidance can be done remotely with human intervention/pre-programmed pathways via satellite and predictive mesoscale eddie modelling.
1.22 If our only concern is maximizing the sequestration of carbon, would upwelling the nutrients into an otherwise unchanged mixed layer stimulate the bio-activity that consumes atmospheric carbon?Physically it might be enough, but there are regulatory constraints, that we have carefully analyzed, resulting in the refinement of Marine Permaculture to meet those guidelines. The London dumping convention, for example, states one cannot add matter to the ocean with the primary purpose of stimulating the ocean unless it is mariculture. Mariculture, of which Marine Permaculture is a form, comprises an explicit allowance with the existing regulations of the London Dumping Convention, Annex 4, which allows for mariculture activities in the open ocean.
1.23 How much area would need to be used for MPs to have a meaningful contribution to climate change?Each 100-hectare MP will sequester up to 2,500 - 6,000 tons of CO2 per year. One goal would be to deploy enough MP’s to sequester 3.5 gigatons of CO2e each year, which is roughly equivalent to the United States’ emissions in 2015 (or about 12% of the global total). Our calculations showed that to achieve our vision of 3.5 gigatons of CO2e each year, we would need to deploy ~1M square km of MPs, which is <1% of the subtropical and tropical Pacific Ocean area. Subtropical ocean deserts comprise 100M km2 in the Pacific, 50M km2 in the Atlantic, and 40M km2 in the Indian Ocean. Kelp today comprises less than 80,000 km2 of area, down substantially from pre-industrial levels.
1.24 Which parts of the ocean make the most sense for MP development?Global warming limits circulation of cooler, nutrient-rich ocean waters and increases the prevalence of warmer, nutrient-deficient, desert-like, subtropical waters of the world. As a consequence, regional changes in fish stocks and plankton production are predicted to decrease productivity in subtropical and tropical waters, expanding poleward. Many valuable seaweed species grow in the subtropical oceans such as the Indian Ocean, where seaweed is a major export. This industry is suffering from warmer waters and decreased nutrients associated with global warming. These areas most affected by global warming, and associated declines in ocean productivity, will be our deployment locations as the impact of MPs in these regions is maximised. <back to top>
1.25 How have you validated MPs?Over the last decade, the Climate Foundation engaged in projects to restore fish productivity in subtropical oceans through Marine Permaculture, ensuring food security. We have also combined renewable energy practices and coral reef conservation, by following nature’s example to provide strong benefits to the economy and local ecosystems.
Key technical components have been validated in epipelagic environments. The Climate Foundation and partners successfully conducted an upwelling experiment using wave-driven ocean pumps to restore overturning circulation and grow algae off the coast of Hawaii. Profiles for commercial viability are being developed with the support received from the Blue Economy Challenge with the Australian Department of Foreign Affairs and Trade.
Further work has continued to validate the biological response of commercially relevant seaweeds to deepwater irrigation. Now that this validation was completed in 2020, the Climate Foundation is in a position to scale to the economically sustainable hectare and beyond.
Financial Questions
2.1 What is the cost to sequester 1,000 tons of carbon? To produce 1,000 tons of seaweed?In the long-run, Climate Foundation estimates it will be cost-negative to sequester 1,000 tons of carbon dioxide equivalent (CO2e). To produce 1,000 tons of seaweed in the long-term, it should ultimately cost less than $80K using MPs, if the DOE targets are met in future years.
2.2 How will you become financially viable?Several MP value chains will be ready to produce initial revenues in the first year. These will include food products based on seaweed, bulk commodity dried seaweed sales and biostimulants. While the revenue from carbon credits alone are unlikely to be sufficient to be cash flow positive in the near term alone, we expect that hectare scale MPs can produce high-value food, feed and fertilizer products resulting in seaweed revenue of over half a million dollars per year. Fish revenue is expected to comprise $1-2K per ton (as fishmeal). High-value extracts ultimately could be producing several times more revenue than the whole seaweed.
2.3 What are the near-term businesses that can be developed from MPs?While there are nearly a dozen business value chains to be derived from Marine Permaculture and open ocean seaweed farming, we believe that some of the most promising near-term business opportunities at present include fertilizer, feed and food markets. Later we believe the sale and commissioning of MP structures themselves; marketing to ports, governments, fishing villages, hotels, and commercial farm fishing operations; seaweed feed supplements; liquid seaweed fertilizer; novel markets for edible seaweed for human consumption); and pigments ($3B market) could provide long-term sustainability to businesses.
2.4 What profitable businesses can be developed from MPs?In the longer term, we expect that commercial fish farm, seaweed farm and fishing operations, fishing ports and villages and individual, medium-sized fishers will be interested in buying or leasing MPs to purify operations, help stimulate seaweed and fish production while generating income. Similarly, coastal tourist locations (cities, cooperatives and local governments) as well as individual resorts and hotels may be interested in growing local, seasonal, ecologically-sound fish and seaweed for guest consumption, as the foodie movement of “farm-to-table” expands to include the ocean farm. We expect that the above customer segments will see MPs as core infrastructure investment or capital expenditures.
As MPs enjoy successful seaweed and fish production, carbon sequestration and reduced cost of ownership for larger enterprise customers, we anticipate increasing requests from the middle market than we would be able to serve directly. A franchise model will allow MP to maintain high quality control and conceptual integrity over the engineering, deployment and service levels, while reducing sales and marketing costs. Further, a growing footprint of MPs and MP customers will have a positive impact on carbon sequestration, ecological and economic resilience.
2.5 How are you planning to make money out of the fish you grow on MPs?Marine Permaculture addresses the entire fishing industry and customers: fishers, distributors, end users and governments; wanting high-quality fish with low concentration of contaminants. For example, top cannery companies, who are suffering from declining fisheries stocks due to nutrient collapse and associated domoic acid blooms, are willing to pay a premium when Marine Permaculture can provide a second fishery. We are enthusiastic about developing sustainable revenue streams from forage fisheries created by Marine Permaculture. We recognize that some of the additional fish production may end up as a public good.
Organizational Questions
3.1 What Intellectual Property is Climate Foundation developing?Climate Foundation is filing several international patent applications to protect Climate Foundation’s inventions in key countries including new technological developments of Marine Permaculture.
3.2 How do you think about execution risk for the next few years at the Climate Foundation?We aim to address one or two key risks at a time, as the technology is developed. For example, the first MPs are expected to be at existing tropical and subtropical seaweed farms. Marine Permaculture will provide deepwater irrigation to these seaweed farms.
During our development period, we will deploy several hectare-scale MPs. Each serial deployment will enable us to refine Marine Permaculture and improve performance. Environmental and technical monitoring of deployed MPs will minimize environmental and technical risks.
Nearly a dozen value chains have been identified for seaweed grown on Marine Permaculture arrays. Existing markets provide low-risk returns for early Marine Permaculture value chains. These markets include seaweed for food, feed and fertilizer. Once MPs are fully developed and low-risk markets accessed, we will enter markets with longer development pipelines and potentially higher revenue to further increase the market for MPs.
3.3 What major policy changes are needed for MPs to be developed over large areas?While there are no policy barriers to commercializing MPs now, recognizing kelp forests as a Blue Carbon sink will accelerate the rollout of MPs for drawdown and facilitate future policy initiatives. Marine Permaculture vessels benefit from 500 years of Admiralty Law and thus have rights of safe navigation on the seven seas.
3.4 Why is marketing Blue Carbon so important?
Thanks to our help, the United Nations Environmental Programme is moving closer to recognizing kelp forests as emerging Blue Carbon sinks. The time is right to move this initiative forward. We went to COP23 (United Nations Conference of the Parties regarding Climate Change) in Bonn last year and met with the President of VCS (Verified Carbon Standard) who reviewed our Marine PermacultureTM plan and has encouraged us to develop a Marine Permaculture VCS methodology based on the phosphate accounting system we have refined for macroalgae and microalgae based on C:P and Redfield ratios. If particulate or dissolved organic carbon is kept at the bottom of the sea for centuries, even if oxidized, it can contribute to long-term carbon stocks as determined by the UN CDM (United Nations Clean Development Mechanism). Once this sink has been established, recognition for offshore kelp forest Blue Carbon sinks will follow. The recognition of kelp developing as an emerging carbon sink will result in additional rev
Technical Questions:
1.1 How much seaweed is produced per Marine Permaculture array (MP) per year?Different seaweed species have different harvesting cycles and biomass production. While red seaweed species are smaller than kelp, they are harvested more often (every six weeks). Kelp grows bigger, but is only harvested every three months. Both are capable of peak growth rates of 5-15% per day, under replete conditions. A square kilometer MP (100 hectares) can grow up to 3,500 dry tons of seaweed per year under optimal conditions.
1.2 Why is irrigation of seaweeds important?Irrigation in MP arrays enables replete macronutrients to be provided to the seaweeds. In subtropical locations, where replete light is available year-round, irrigation enables four growing seasons for kelp and up to eight growing seasons for some red seaweeds. Most regions of the world may not have replete nutrients year-round, thus irrigation during the “dry season” (low productivity) with deeper water enables replete growth rates to be maintained. Irrigation also improves the consistency of crops from one harvest to another, and enables thermal management of the seaweeds. It keeps the farm running at 100% capacity factor. Organisms in the ocean mostly rely on the ocean ambient temperature and do not thermally regulate. Peak sea surface temperature anomalies of 2 degrees is analogous to a human body experiencing a fever of 2 degrees. It has a big effect on performance and metabolism. Controlled irrigation enables MP to control temperatures in the seaweed forest. Our organisation was the first to show that irrigation with deep water can reverse coral bleaching in the field and reduce some effects of global warming on marine organisms. We have started with the MP seaweed forests to showcase this capability.
1.3 How does irrigation work?We use on-site solar, wind, thermal or wave energy to bring cooler water up to the mixed layer and bring it into thermal equilibrium with the surface water. Then we pass the cooler water through perforated diffuser pipes that irrigate the attached seaweed forest, supplying nutrients to the seaweed for growth.
1.4 Why is it important to irrigate the seaweed?With global warming, overturning circulation is reduced in subtropical and tropical oceans. As a result, those oceans stably stratify, decimating nutrient levels. Without nutrients, seaweed growth halts, seaweed becomes sickly and it starts to die. Irrigating the seaweed with deeper, cooler water provides nutrients and keeps the seaweed cooler in its target temperature range. This irrigation results in replete conditions for the seaweed to grow, resulting in higher fluxes per hectare and higher yields.
1.5 How do you ensure buoyancy for the cooler water being brought up?We have established a patent-pending buoyancy condition for the cooler water that applies to over half of the subtropical oceans. A heat exchanger with 2 degrees °C approach temperature can establish buoyancy for cooler water that has a salinity 1 part-per-thousand lower than the mixed layer. For the first time, we have established buoyancy criteria for efficient use of upwelled nutrients. Before this discovery, deep water was used to grow kelp, but most of it sank back to the thermocline. With Marine Permaculture, nearly all of the upwelled water grows algae, with over 90% phosphate utilization.
1.6 Does MP seaweed grow faster than naturally occurring seaweed forests?Yes, by understanding the ocean environment and the environmental variables most affecting growth, we expect MPs will enjoy higher yields than in the wild by providing consistent, year-round irrigation, whereas natural kelp forests may experience replete nutrients but may not have replete light in the winter and may be nutrient-limited during the warm summer months, when nutrient levels can be lower. Also, natural kelp forests tend to grow in high latitudes for thermal reasons and thus may be light-limited all winter, whereas Marine Permaculture forests can be grown in subtropical latitudes and get replete light four seasons per year and replete nutrients four seasons per year.
1.7 How much carbon can be sequestered as an ancillary benefit with MPs? Each 100-hectare MP array in subtropical oceans has the potential to draw down 2,500-6,000 tons of carbon dioxide per year from the atmosphere and associated surface ocean waters. At an average of 1 ton CO2e per ton of seaweed, and 50 tons (dry weight) of seaweed per hectare, each hectare can fix an average of 50 tons of CO2e per year.
Research has confirmed that carbon fixation in kelp forests can exceed the carbon fixation per hectare of terrestrial forests, partly because terrestrial plants typically photosynthesize at 0.2-2% efficiency, whereas ocean seaweed efficiency can exceed 8%. With far more open ocean available to us than the available area for old-growth tropical rainforest, the Marine Permaculture approach has distinct advantages of scalability.
1.8 How are we sure this is carbon negative and not just cycling carbon in a loop?We know the MP process is carbon negative by analysing the Redfield ratio for seawater, plankton and seaweed. “The Redfield ratio or Redfield stoichiometry is the atomic ratio of carbon, nitrogen and phosphorus found in phytoplankton and throughout the deep oceans. This empirically developed stoichiometric ratio was originally found to be C:N:P = 106:16:1 (and has more recently been revised to 117:14:1).” However, for seaweeds the C:P redfield ratio can range from 220:1 to 800:1.
We have developed a rigorous methodology for tracking carbon in the ocean. To measure the carbon, we track the phosphorus. That is because the phosphorus, unlike nitrogen and carbon, does not transfer to the air to any significant degree. Thus, in the pelagic ocean, it serves as a reference for tracking the carbon being used. Ultimately, over 90% of the phosphorus will be used by the seaweed. For every atom of phosphorus used 220-800 carbon atoms are used for seaweed growth. This means that for every carbon atom upwelled at least twice as many carbon atoms can be sunk to the bottom of the ocean.
If particulate or dissolved organic carbon is kept at the bottom of the sea for centuries, even if oxidized, it can contribute to long-term C stocks as determined by the UN CDM. The seaweed processed at sea, sinks hundreds of meters per day to the bottom of the sea. In a few days it reaches the seafloor, mostly still intact. In some locations the deep water is anoxic, so the carbon will remain in under-oxidized form for millennia. In other regions, the carbohydrate of the seaweed will be eventually respired and oxidized. There is over 1,000 times more oxygen in the deep ocean than is required to fully oxidize 1,000 gigatons of carbohydrate (carbon) from seaweed. Said another way, if all 1,000 gigatons of carbohydrate (carbon) were oxidized and distributed in the deep ocean, it would only decrease the oxygen level by 0.1%. This deep carbon also remains underwater for millennia. The rule of thumb many physical oceanographers use is once the carbon is sunk >1km below the surface, the median outcropping time is 100 to 2,000 years (Dr. Raymond Schmitt, WHOI Physical Oceanographer, NAS). This timescale is valid whether through the mechanism of vertical eddy diffusion or through lateral advection to western boundary currents. All of Marine Permaculture seaweed residual carbon can be sequestered to depths of more than 1 km in a matter of a couple of days at normal sink rates.
The United Nations grants a carbon credit, if the methodology supports a sequestration time of 100 years or longer. Some of our anticipated deployment sites are among the largest anoxic basins in the world. In these sites, kelp forest Blue Carbon sinks remain on the seafloor for millennia.
1.9 Can you describe core design details of an MP array?Marine Permaculture uses renewable energy to lift colder, denser water bearing nutrients from below the “nutricline”, near the thermocline, to the nominal MP substrate depth of <25m. Wave, solar or ocean thermal power can be sufficient to restore circulation. Under wave energy, a surface buoy connects to a low-stretch, ¼” steel cable going 30-40 meters deep to a flapper valve pump that channels the cool, nutrient-rich water through a flexible, curved high-density polyethylene (HDPE) pipe that reaches depths of 200-400m. Before reaching the seaweed forest, this upwelled water is warmed in the heat exchanger to establish buoyancy. The water then irrigates the kelp forest through perforated diffusion pipes. Cable lengths attached to surface buoys determine the depth of the system.
In one embodiment, a self-adjusting chain system enables the depth of the Marine Permaculture to vary over time in a way consistent with maximal growth rates. HDPE pipe and welds have proven to be highly flexible and resilient in deep ocean deployments at the Natural Energy Lab, Hawaii Authority (NELHA) and other locations for over 40 years.
We also have a technology roadmap in place to develop more cost-effective technologies over the next three years to bring deep nutrient-rich water to the seaweed arrays, as currently upwelling involves several of the MP’s most costly elements. We estimate that such a system will reduce costs significantly.
1.10 Can you compare MP seaweed production to nearshore operations?Most of the world’s seaweed production occurs in coastal zones, which often have multiple, competing uses and little space to increase algae cultivation areas. Intertidal and subtidal zones are in high demand for tourism and development, but epipelagic waters are plentiful, enabling Marine Permaculture deployment and increasing productivity.
Marine Permaculture aims to restore natural upwellingand associated regional macronutrient cycling in offshore waters. This will enable replete macroalgae production in pelagic waters and increasing cultivation areas that are resilient to climate disruption. Unlike traditional mariculture, Marine Permaculture arrays are thermally stabilized with cool, deep water and can survive the greatest heat waves and El Ninos. During these periods, many traditional seaweed beds are lost due to lack of nutrients and high temperatures.
1.11 Is it possible to integrate mussel farming?Integrated mussel farms could be an option and might work best for smaller MPs, close to shore where plankton abundance is higher and advection of nutrients and plankton is slower. Mussels could offer additional income streams for fishers and pose an opportunity for carbon sequestration. However, mussels require higher plankton density than fish for optimal production. These levels are not assured yet on the open ocean, whereas the plankton levels are adequate for finfish such as sardines, anchovies, salmon and game fish. With over half a dozen revenue streams identified for Marine Permaculture with seaweed and fish, we have not focused as much on mussels. Our large-scale deployment in the open ocean will be specifically designed to produce maximum seaweed and fish yields and therefore, mussels are not planned to be part of the system at present.
1.12 Are piracy and overfishing risks?The initial sites will be in partner-managed or protected waters. Piracy and overfishing are risks in some MP locations. However, this will be mitigated by the limited visibility of MP from a distance, and by utilizing existing Marine Protected Area regulations, Admiralty Law, the Law of the Sea, strict fishing policies, remote monitoring technology, and community engagement and relations.
1.13 Are MPs safe from large ocean-going ships and storms?MPs remain at a nominal depth of up to 25 meters to eliminate risks to navigation. This depth also ensures MP resilience under hurricane conditions. Ten-meter hurricane wave swells typically break in 18 meters of water depth. Light quality and quantity (green and blue at 25 m depth) is still sufficient for seaweed and plankton growth in the open ocean.
1.14 How much maintenance is required to keep MPs functional?All components of the MP arrays are durable, with low maintenance profiles, enabling infrequent preventive maintenance intervals of months to years, once fully developed. Marine Permaculture technology will create conditions that enable seaweed to survive in the open ocean, using renewable energy and without additional fertilizer inputs or operation-intensive infrastructure such as tanks, nets, fish feed or deepwater moorings. Seaweed irrigation with nutrient rich water continues automatically and unattended with renewable energy, keeping operation and maintenance costs low. The kelp cutter will harvest each MP once per season and sustainably harvest up to 900 tonnes of kelp in one day, cropping only the top 1-2 meters of the kelp forest to keep the kelp growing at their maximum rate.
1.15 What types of seaweed will be produced? What is the difference among seaweeds?Marine Permaculture enables multiple trophic and spatial niches and increases production per unit area. Judicious selection of local native and compatible fast-growing species, e.g., Macrocystis or Ecklonia, helps to maximize yield and will be the “backbone” of our offshore Marine Permaculture. Further selection of local species depends on seedling availability and market demand. We identified species for fast growth, high-value bioproduct production and improved resiliency of fish habitat. In particular, Macrocystis can grow up to 1/2 meter per day, Eucheuma provides high-quality carrageenan and high-value nutraceuticals, and Asparagopsis provides “supreme seaweed”, for the highly valued limu kohu of Hawaii, and the reduction of enteric methane emissions from ruminant livestock. Eucheuma cottonii (Kappaphycus alvarezii) and E. spinosum (E. denticulatum) have established commercial markets today.
1.16 What are seaweeds used for?Since the 1950’s, seaweed culture has been developed and represents more than 99% of the global seaweed production today. The world production is dominated by Asian countries (99%), with China, Indonesia and Philippines as global production leaders. Seaweed products comprise food, cosmetics, feed supplements, agricultural biostimulants, pharmaceuticals, biofuels and recently fabrics. The biggest industry is the food industry in which seaweeds are directly or indirectly consumed by people as sea vegetables. The second largest industry is hydrocolloid industry, where seaweed contains carrageenan, agars and alginates used in pharmaceutical, cosmetics, textile, paint, edible food coatings, biomedical applications, microbiology, molecular biology or animal feed applications. Other additives are also extracted from seaweed and used in food, cosmetics, healthcare or agrochemistry industries. They can be used also for wastewater treatment.
1.17 How much of the MP seaweed forest do you harvest each season?In the case of a Macrocystis kelp forest, we harvest to a depth of 1.5 meters, leaving the remainder of the 25-meter depth untouched for maximal regrowth in the coming season. In the 90-day season, the kelp can grow another stipe of up to 45 meters. When the kelp reaches 25 meters it begins to grow horizontally along the surface. Thus, approximately half of the seaweed can be harvested when the kelp is harvested at 1.5m depth. This approach is intended to maximize yields while preserving ecosystem function and MP growth. Such growth is regenerative in the sense that the revenue supports increased ecosystem services, and the ecosystem responds with higher yields. The deployment location, specific local market opportunities as well as the economic needs of coastal participating communities will determine which value streams will be initially chosen. If the economic focus lies on fish, little seaweed will be harvested to produce seaweed products, leaving almost all the harvested seaweed for carbon sequestration. While harvesting most of the seaweed for food may leave less for carbon sequestration, extracting high-value products such as phycobiliproteins from seaweed, uses only 1% of the carbon, leaving over 90% of the carbon to go to Blue Carbon sinks to the middle and deep ocean.
1.18 How can MPs benefit from onshore renewable energy projects?Hotels with 5MW air conditioning load or greater, located close to the beach, can use deep seawater cooling for air conditioning in conjunction with Marine Permaculture. This integration also provides a unique opportunity to differentiate from competition and an eco-touristic advantage in having an identity that is cleaner and more environmentally friendly than alternatives. A 5MW system is enough for a few-hectare MP. Larger systems could be 100 MW or more. A 2.5m pipe is sufficient for 100 hectares or more, so the size of the array is a function of how much water is being upwelled. These arrays will also protect the corals near the resorts (the hotel reef) from thermally induced photobleaching.
1.19 What are some objections to the MP approach?Critics have argued that Marine Permaculture does not necessarily restore kelp forest, only creating one offshore in a different place. In response it is helpful to note that Marine Permaculture regenerates regional ecosystem services provided by kelp forests and other seaweed forests. Marine Permaculture provides cooler, deeper waters needed by seaweed and a feeding and breeding ground for forage fish. Through these ecosystem services we can enhance the productivity, climate resilience and survival of local kelp forests and other local ecosystems. In addition, kelp forests reduce ocean acidification, increase oxygen levels and sequester carbon far downstream from the forest locations. The ecosystem service benefits accrue regionally, including increasing oxygen levels, reduced ocean acidification, restored natural upwelling and regional carbon sequestration. The loss of upwelling in the past decades is particularly concerning. Marine Permaculture helps to restore that upwelling while obtaining a sustainable yield.
Critics may also argue that MP would displace some ecosystem offshore. However, the carbon flux of such ecosystems and the biomass density of such pelagic waters is so much lower than the kelp forest, that it is commonly called by Sir David Attenborough “the mostly empty ocean.” Using <1% of such mostly empty regions to ensure global food security, restore regional biological processes and reduce human suffering represents a responsible approach to addressing climate challenges.
Some question whether MP could contribute to harmful algal blooms. There are many factors such as reduced temperature and improved overturning circulation that actually moves the photozone away from harmful algal blooms. We plan to monitor for such blooms, improbable as they may be, as well as other environmental consequences.
Some critics have suggested that we would attract fish so strongly that they will no longer migrate. In a sense, such a development may be better than losing those species entirely. Marine Permaculture aims to produce more fish, not just have the existing fish stay at the MP. In any case, the fish are free to come and go and depart on their annual migrations at will. We can also control how many fish we harvest to ensure sustainability.
1.20 Are larger open-ocean MPs preferable?We envision MPs in the range of one to 100 hectares. The larger MPs may enjoy economies of scale, potentially increasing efficiency, but the optimal size has yet to be proven. Near shore installations compete with other area uses and will be far more bureaucratic to permit and operate. We expect that sustainable seaweed mariculture with deepwater irrigation will be in the 1-100 Ha range.
1.21 Can MPs be “moved” remotely?Multiple associated MPs enable large-scale cultivation of macroalgae in the open ocean. In the long term, self-guided arrays can use shear from mesoscale eddies for propulsion normal to current directions, providing means for navigation and guidance. These mesoscale eddies are analogous to thermals in the sky utilised by soaring birds to achieve navigational goals. The system can be guided using a remotely controlled system similar to those used by Liquid Robotics developed in Silicon Valley and used by Boeing in their DOD programs. Navigational guidance can be done remotely with human intervention/pre-programmed pathways via satellite and predictive mesoscale eddie modelling.
1.22 If our only concern is maximizing the sequestration of carbon, would upwelling the nutrients into an otherwise unchanged mixed layer stimulate the bio-activity that consumes atmospheric carbon?Physically it might be enough, but there are regulatory constraints, that we have carefully analyzed, resulting in the refinement of Marine Permaculture to meet those guidelines. The London dumping convention, for example, states one cannot add matter to the ocean with the primary purpose of stimulating the ocean unless it is mariculture. Mariculture, of which Marine Permaculture is a form, comprises an explicit allowance with the existing regulations of the London Dumping Convention, Annex 4, which allows for mariculture activities in the open ocean.
1.23 How much area would need to be used for MPs to have a meaningful contribution to climate change?Each 100-hectare MP will sequester up to 2,500 - 6,000 tons of CO2 per year. One goal would be to deploy enough MP’s to sequester 3.5 gigatons of CO2e each year, which is roughly equivalent to the United States’ emissions in 2015 (or about 12% of the global total). Our calculations showed that to achieve our vision of 3.5 gigatons of CO2e each year, we would need to deploy ~1M square km of MPs, which is <1% of the subtropical and tropical Pacific Ocean area. Subtropical ocean deserts comprise 100M km2 in the Pacific, 50M km2 in the Atlantic, and 40M km2 in the Indian Ocean. Kelp today comprises less than 80,000 km2 of area, down substantially from pre-industrial levels.
1.24 Which parts of the ocean make the most sense for MP development?Global warming limits circulation of cooler, nutrient-rich ocean waters and increases the prevalence of warmer, nutrient-deficient, desert-like, subtropical waters of the world. As a consequence, regional changes in fish stocks and plankton production are predicted to decrease productivity in subtropical and tropical waters, expanding poleward. Many valuable seaweed species grow in the subtropical oceans such as the Indian Ocean, where seaweed is a major export. This industry is suffering from warmer waters and decreased nutrients associated with global warming. These areas most affected by global warming, and associated declines in ocean productivity, will be our deployment locations as the impact of MPs in these regions is maximised. <back to top>
1.25 How have you validated MPs?Over the last decade, the Climate Foundation engaged in projects to restore fish productivity in subtropical oceans through Marine Permaculture, ensuring food security. We have also combined renewable energy practices and coral reef conservation, by following nature’s example to provide strong benefits to the economy and local ecosystems.
Key technical components have been validated in epipelagic environments. The Climate Foundation and partners successfully conducted an upwelling experiment using wave-driven ocean pumps to restore overturning circulation and grow algae off the coast of Hawaii. Profiles for commercial viability are being developed with the support received from the Blue Economy Challenge with the Australian Department of Foreign Affairs and Trade.
Further work has continued to validate the biological response of commercially relevant seaweeds to deepwater irrigation. Now that this validation was completed in 2020, the Climate Foundation is in a position to scale to the economically sustainable hectare and beyond.
Financial Questions
2.1 What is the cost to sequester 1,000 tons of carbon? To produce 1,000 tons of seaweed?In the long-run, Climate Foundation estimates it will be cost-negative to sequester 1,000 tons of carbon dioxide equivalent (CO2e). To produce 1,000 tons of seaweed in the long-term, it should ultimately cost less than $80K using MPs, if the DOE targets are met in future years.
2.2 How will you become financially viable?Several MP value chains will be ready to produce initial revenues in the first year. These will include food products based on seaweed, bulk commodity dried seaweed sales and biostimulants. While the revenue from carbon credits alone are unlikely to be sufficient to be cash flow positive in the near term alone, we expect that hectare scale MPs can produce high-value food, feed and fertilizer products resulting in seaweed revenue of over half a million dollars per year. Fish revenue is expected to comprise $1-2K per ton (as fishmeal). High-value extracts ultimately could be producing several times more revenue than the whole seaweed.
2.3 What are the near-term businesses that can be developed from MPs?While there are nearly a dozen business value chains to be derived from Marine Permaculture and open ocean seaweed farming, we believe that some of the most promising near-term business opportunities at present include fertilizer, feed and food markets. Later we believe the sale and commissioning of MP structures themselves; marketing to ports, governments, fishing villages, hotels, and commercial farm fishing operations; seaweed feed supplements; liquid seaweed fertilizer; novel markets for edible seaweed for human consumption); and pigments ($3B market) could provide long-term sustainability to businesses.
2.4 What profitable businesses can be developed from MPs?In the longer term, we expect that commercial fish farm, seaweed farm and fishing operations, fishing ports and villages and individual, medium-sized fishers will be interested in buying or leasing MPs to purify operations, help stimulate seaweed and fish production while generating income. Similarly, coastal tourist locations (cities, cooperatives and local governments) as well as individual resorts and hotels may be interested in growing local, seasonal, ecologically-sound fish and seaweed for guest consumption, as the foodie movement of “farm-to-table” expands to include the ocean farm. We expect that the above customer segments will see MPs as core infrastructure investment or capital expenditures.
As MPs enjoy successful seaweed and fish production, carbon sequestration and reduced cost of ownership for larger enterprise customers, we anticipate increasing requests from the middle market than we would be able to serve directly. A franchise model will allow MP to maintain high quality control and conceptual integrity over the engineering, deployment and service levels, while reducing sales and marketing costs. Further, a growing footprint of MPs and MP customers will have a positive impact on carbon sequestration, ecological and economic resilience.
2.5 How are you planning to make money out of the fish you grow on MPs?Marine Permaculture addresses the entire fishing industry and customers: fishers, distributors, end users and governments; wanting high-quality fish with low concentration of contaminants. For example, top cannery companies, who are suffering from declining fisheries stocks due to nutrient collapse and associated domoic acid blooms, are willing to pay a premium when Marine Permaculture can provide a second fishery. We are enthusiastic about developing sustainable revenue streams from forage fisheries created by Marine Permaculture. We recognize that some of the additional fish production may end up as a public good.
Organizational Questions
3.1 What Intellectual Property is Climate Foundation developing?Climate Foundation is filing several international patent applications to protect Climate Foundation’s inventions in key countries including new technological developments of Marine Permaculture.
3.2 How do you think about execution risk for the next few years at the Climate Foundation?We aim to address one or two key risks at a time, as the technology is developed. For example, the first MPs are expected to be at existing tropical and subtropical seaweed farms. Marine Permaculture will provide deepwater irrigation to these seaweed farms.
During our development period, we will deploy several hectare-scale MPs. Each serial deployment will enable us to refine Marine Permaculture and improve performance. Environmental and technical monitoring of deployed MPs will minimize environmental and technical risks.
Nearly a dozen value chains have been identified for seaweed grown on Marine Permaculture arrays. Existing markets provide low-risk returns for early Marine Permaculture value chains. These markets include seaweed for food, feed and fertilizer. Once MPs are fully developed and low-risk markets accessed, we will enter markets with longer development pipelines and potentially higher revenue to further increase the market for MPs.
3.3 What major policy changes are needed for MPs to be developed over large areas?While there are no policy barriers to commercializing MPs now, recognizing kelp forests as a Blue Carbon sink will accelerate the rollout of MPs for drawdown and facilitate future policy initiatives. Marine Permaculture vessels benefit from 500 years of Admiralty Law and thus have rights of safe navigation on the seven seas.
3.4 Why is marketing Blue Carbon so important?
Thanks to our help, the United Nations Environmental Programme is moving closer to recognizing kelp forests as emerging Blue Carbon sinks. The time is right to move this initiative forward. We went to COP23 (United Nations Conference of the Parties regarding Climate Change) in Bonn last year and met with the President of VCS (Verified Carbon Standard) who reviewed our Marine PermacultureTM plan and has encouraged us to develop a Marine Permaculture VCS methodology based on the phosphate accounting system we have refined for macroalgae and microalgae based on C:P and Redfield ratios. If particulate or dissolved organic carbon is kept at the bottom of the sea for centuries, even if oxidized, it can contribute to long-term carbon stocks as determined by the UN CDM (United Nations Clean Development Mechanism). Once this sink has been established, recognition for offshore kelp forest Blue Carbon sinks will follow. The recognition of kelp developing as an emerging carbon sink will result in additional rev