So What's the Plan?

The web pages so far describes the rationale and rough 'vision' for attacking the CO2 problem (big seaweed farms).   Now we go into some specific initiatives.    There are three main initiatives

  1. Make Large Scale Carbon Sequestering Seaweed Farms Possible - this really is the 'big idea' that could really help climate change in a big way.  Unfortunately, it assumes things like bio-engineering seaweed, which we don't know how to do.   Thus while this is the 'ideal' plan, it will also require an indeterminate amount of R&D to make it a reality.  Thus this plan's work stream is a series of research initiatives.  

  2. Build a fleet of Sargassum Mowers - As a fallback, we can start sequestering carbon in a reasonably large scale (millions but not billions of tons per year), by mowing the existing blooms of sargassum.   For this we need a fleet of autonomous catamarans that are powered by wind and sun that can mow the windrows of seaweed.    The business model is carbon credits as well as fees that beach owners will pay to reduce the amount of seaweed washed up on shore (you can tailor where you mow if all owners don't pay).  This plan has risks, but unlike the first option there is nothing that is known to block implementation.  

  3. Make Seaweed Farming for Food Cheap - This is the fallback to the fallback.   It is intentionally very low tech.   Basically we want to make current seaweed farming (for food) as efficient as possible and scale it up as much as possible.   While this does not directly sequester carbon (since we eat the seaweed), growing seaweed is less carbon intensive than growing land crops, and it provides opportunities to really understand what it would take to scale up seaweed farms.   A lot of valuable lessons will be learned.    If we can make this cheap enough, we could simply allow the seaweed to sink instead of harvesting it to sequester the carbon (assuming the sea is deep there).

Lets look at each of these plans in more detail...

Work Streams for Large Carbon Sequestration Farms

Research Needed 

  • Experimental evidence that biomass in the deep ocean stays sequestered.

  • Research categorizing seaweed candidate species for carbon sequestration along with important properties (growth rate, climate, lifetime, vegatative propagation ...)

  • Research gene editing techniques that will work on seaweed (CRISPR Cas9?) Work out all the details.

  • Find out what seaweeds have already had their genome sequenced.  Determine the logistics of getting the genome for a seaweed if we need it (likely the seaweed we pick will not be one that has been sequenced (because only commercial seaweeds have been done so far).  

  • Review seaweeds species for natural structures that could hijacked to make 'pods'.   Could we repurpose pneumatocysts?   Maybe kelp holdfasts could be repurposed.  The more we can 'steal' from nature, the easier/after it will be to bioengineer what we need. 

  • Determine if it is feasible to transfer genes that make microalgae produce large amounts of oil into seaweed.  This may  make biofuel practical (since we can harvest the oil simply by squeezing). 

  • Research how practical it is to get nutrients simply by pumping water up from lower in the ocean (which is more nutrient rich)

  • Research how to integrate nitrogen-fixation into a seaweed farm.   Cyanobaceteria can do it, what else?  Can we splice it into the seaweed itself?  Should we make a little symbiosis (like azolla), or built a larger eco-system?.  

  • Research  issues with pest control (Will micro-algae compete with the seaweed, are there other pests or diseases).  


This is not everything, and you can see that there are plenty of things for hard core researchers.    This is what makes this a longer term project.   In addition some of the items in the Seaweed for Food Project will also be needed (one of the values of that project is the experience is applicable to this project).  


Work Streams for Sargassum Mowers

Research Needed 

  • Determine why the Sargassum blooms are happening (they started in 2011), and estimate if they are likely to continue.

  • Determine bounds on 'collateral damage' to the ecosystem of large scale mowing (however arguably it can't be that bad since it did not exist before 2011).   

  • Make contacts with beach owners to find out if they are interested in a solution, and what they pay now for beach cleaning.   Estimate how 'targeted' the mowing can be (can you determine which beaches benefit from mowing in a particular place).

  • Determine details for carbon credits and whether the combination of carbon credits and beach owner payments could work economically.   

Build a Prototype Sargassum Mower

  • Investigate SailDrone technology and whether a collaboration is possible.  

  • Confirm what kind of cutting is necessary to insure that the Sargassum will sink (thus need real samples from a variety of times and places)
  • Build a small scale prototype (something you can disassemble and carry, probably a meter or so in length). The main purpose is to prototype the cutter assembly and estimate how much power would be needed to run it.   The goal is to make this totally wind/solar powered, but if necessary we could supplement.   This small scale prototype would be human controlled. 

  • Build the full sized (probably 5 meters long) prototype.  

  • Prototype computer vision system that could automatically see the windrows of seaweed in the water and guide the boat to mow it.  

  • Research/Test how the catamaran would work in bad weather (The basic strategy however is to avoid bad weather with good weather reports). 

  • Design/Build a system that estimates the amount of seaweed mowed (we get credits by the ton so we need to know what we should get credit for). 

This is just some highlights.    A fuller list is offline.   Some of the items are already in progress.    Email to address in footer if interested in more detail.    


Work Streams: Seaweed for Food

In theory growing seaweed for food is meant to be 'easy' because we are already doing it.  However there is still plenty research and things to improve upon.

Research Items 

  • Determine the market potential for each of the current commercial seaweeds, and evaluate how much each market could grow.   In particular is it possible to make inroads into selling seaweed in the US market.

  • Currently commercial seaweeds are grown from spores.   This is labor intensive.   Are there alternatives (vegatative growth)?     

  • Research whether there are other species that have good food and growing properties that are not yet commercial.     

  • Experiment with mass automation.   The goal is to get to a degree of automation similar to combines for land crops.    Ideally processing can happen AT SEA (not unlike what has happened with fish processing). 

  • Determine the best sources of fertilizers.    Ideally biosolids could be used for phosphorous and nitrogen.   Is nitrogen fixation by bacteria valuable? 

  • These farms are likely to be close to land (for convenience since we don't need deep waters).   Research the land use rules, and other practical impediments as the farm size grow.

  • Determine if seaweed can be used as feedstocks for industrial food (think textured vegetable protein, tofu, corn syrup ...), or as animal feed.  

Again, this just a sample of the work items.   Even in this 'straightforward' plan, there is plenty to figure out to make something real.  


OK that's the plan(s).   What now?


Congratulation, you have made it through the end of this presentation.       There is  plenty more to say, but that information is not yet on this web site.   Hopefully the ideas presented here have sparked some enthusiasm to get involved.   If so click the 'How to help' button below which will tell you how you can learn more and participate from here.   You can also learn more about related efforts like Project Drawdown to cut our emissions (which we really need to do because it is cheaper than negative carbon).   Click that button for more.