Difference between revisions of "Offshore algae"

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== Description ==
 
== Description ==
  
Algae are bred, provided with a lot of nutrients and allowed to grow rapidly in open water, then harvested before decomposing.
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Algae are bred and provided with a lot of nutrients, then grow rapidly in open water, and are finally harvested and prevented from decomposing.
  
The intention is to utilise the rapid growth rate of algae as well as the resources of open water (including sunlight, nutrients and water) to sequester greenhouse gases, while minimising unwanted impacts. The economics may be improved by using the algae, for example as food, fuel or fertilizer.
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The intention is to utilise the rapid growth rate of algae as well as the resources of open water (sunlight, nutrients and water) to sequester greenhouse gases, while minimising unwanted impacts. The economics may be improved by using some of the algae, for example as food, fuel or fertiliser.
  
To utilize substantial areas while minimising environmental impact and sensitivity to weather, the algae breeding, feeding and deployment could be performed by ships so that any given location is impacted for a short period of time on each occasion.
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The algae breeding, feeding and deployment could be performed in fixed locations with prevailing currents, or with ships. Fixed locations are likely to be more economical and may be particularly palatable in marine deserts. Ships may facilitate utilisation of substantial areas while reducing sensitivity to weather and environmental issues (with any given location being impacted for a short period of time on each occasion).
  
Algae would likely be selectively bred or genetically engineered for the purpose.
+
The harvested algae would be dealt with in a way that prevents the greenhouse gases from re-entering the atmosphere. This is currently being considered as a separate challenge in it's own right, which at least seems more achievable than dealing directly with greenhouse gases in the atmosphere. To illustrate, ideas for dealing with the algae including converting it to oil or drying and burying it - these ideas have not been thoroughly thought through. It might be practical to extract some of the nutrients for re-use in the cycle.
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Algae would likely be selectively bred for the purpose.
  
 
== Feasibility ==
 
== Feasibility ==
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In the areas where the algae is growing, the algae would consume much of the sunlight and nutrients. We hope that the detrimental impacts could be minimised by operating in each area for a short period of time.
 
In the areas where the algae is growing, the algae would consume much of the sunlight and nutrients. We hope that the detrimental impacts could be minimised by operating in each area for a short period of time.
  
There would be risk of failure to sufficiently harvest the algae, which would result in an each receiving prolonged exposure and the algae decomposing in the water (which would be likely to consume much of the oxygen in the water causing other marine life to suffocate). We hope that these risks could be mitigated by safe operating practises, using algae that is easy to harvest, using algae that struggles to reproduce outside the artificial breeding conditions, and perhaps using an algae the decomposes at a rate or in a way that is less harmful to other marine life.
+
There would be risk of failure to sufficiently harvest the algae, which would result in an area receiving prolonged exposure and the algae decomposing in the water (which would be likely to consume much of the oxygen in the water, causing other marine life to suffocate). We hope that these risks could be mitigated by safe operating practises, using algae that is easy to harvest, using algae that struggles to reproduce outside the artificial breeding conditions, and perhaps using an algae the decomposes at a rate or in a way that is less harmful to other marine life.
 +
 
 +
If selective breeding of algae turns out to be inadequate, genetic engineering may be justified. Either way, there is no guarantee that suitable algae would result.
  
 
There may be difficulty in suitably disposing of harvested algae.
 
There may be difficulty in suitably disposing of harvested algae.
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[Please help with any useful information or metrics on current and expected economics.]
 
[Please help with any useful information or metrics on current and expected economics.]
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== See also ==
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* [https://en.m.wikipedia.org/wiki/Algaculture Wikipedia article on aquaculture]
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* [https://en.m.wikipedia.org/wiki/Carbon_capture_and_storage Wikipedia article on carbon capture and storage]
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== Other comments/feedback received ==
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*From [https://wt.social/post/climate-change/zl71wxr5252262581522 Adam Kirk on wt.social]: I'd like to see this idea used in conjunction with deep sea oil wells. Specifically, once extraction is "completed" and the well has run dry, it would be a neat idea to turn the pump upside down and start pumping an algae-water slurry back into the well. As much algae as possible. Use the algae to collect carbon from the atmosphere, and then the pump to sequester the carbon below bedrock. Fill in the line and leave it to turn into oil once again in a few thousand years.
 +
* From [https://wt.social/post/climate-change/zl71wxr5252262581522 Martin Wolterding on wt.social]: (Paraphrased) Rather than genetically engineering algae, it may be possle to bring nutrient right water from great depths to the surface - with the nutrients causing algal growth that will remove CO2 from the atmosphere.
 +
* From [https://wt.social/post/climate-change/zl71wxr5252262581522 Tony Nony on wt.social]: We need to remove CO2 from the air as permanently as we can. So long as the algae remain alive, healthy and growing, then they're another form of plant life 'sequestering' carbon. One form (phytoplankton) does -half- of all photosynthesis on Earth. The WPedia articles says that 40% of them have gone missing since 1950 (possibly due to ocean warming). So to use algae as one carbon solution, you'd need to find out which species are hardiest. Some of them are among the fastest-growing renewable biomass sources (WP:see Algae#Energy_source), a resource that's expected to take off in the next decade.

Latest revision as of 08:08, 12 April 2020

Description[edit]

Algae are bred and provided with a lot of nutrients, then grow rapidly in open water, and are finally harvested and prevented from decomposing.

The intention is to utilise the rapid growth rate of algae as well as the resources of open water (sunlight, nutrients and water) to sequester greenhouse gases, while minimising unwanted impacts. The economics may be improved by using some of the algae, for example as food, fuel or fertiliser.

The algae breeding, feeding and deployment could be performed in fixed locations with prevailing currents, or with ships. Fixed locations are likely to be more economical and may be particularly palatable in marine deserts. Ships may facilitate utilisation of substantial areas while reducing sensitivity to weather and environmental issues (with any given location being impacted for a short period of time on each occasion).

The harvested algae would be dealt with in a way that prevents the greenhouse gases from re-entering the atmosphere. This is currently being considered as a separate challenge in it's own right, which at least seems more achievable than dealing directly with greenhouse gases in the atmosphere. To illustrate, ideas for dealing with the algae including converting it to oil or drying and burying it - these ideas have not been thoroughly thought through. It might be practical to extract some of the nutrients for re-use in the cycle.

Algae would likely be selectively bred for the purpose.

Feasibility[edit]

This is just an idea.

It currently seems physically possible. If it could be proven to work in a test environment and the economics seemed promising, we would still anticipate environmental and political challenges.

There is likely to be difficulty in obtaining appropriate algae.

In the areas where the algae is growing, the algae would consume much of the sunlight and nutrients. We hope that the detrimental impacts could be minimised by operating in each area for a short period of time.

There would be risk of failure to sufficiently harvest the algae, which would result in an area receiving prolonged exposure and the algae decomposing in the water (which would be likely to consume much of the oxygen in the water, causing other marine life to suffocate). We hope that these risks could be mitigated by safe operating practises, using algae that is easy to harvest, using algae that struggles to reproduce outside the artificial breeding conditions, and perhaps using an algae the decomposes at a rate or in a way that is less harmful to other marine life.

If selective breeding of algae turns out to be inadequate, genetic engineering may be justified. Either way, there is no guarantee that suitable algae would result.

There may be difficulty in suitably disposing of harvested algae.

The harvested algae may be sufficiently valuable or desirable that economics or politics facilitate roll-out.

Impact[edit]

If this works and were to be deployed at scale, we think it stands a chance of significantly reducing global greenhouse gas levels.

Economics[edit]

[Please help with any useful information or metrics on current and expected economics.]

See also[edit]

Other comments/feedback received[edit]

  • From Adam Kirk on wt.social: I'd like to see this idea used in conjunction with deep sea oil wells. Specifically, once extraction is "completed" and the well has run dry, it would be a neat idea to turn the pump upside down and start pumping an algae-water slurry back into the well. As much algae as possible. Use the algae to collect carbon from the atmosphere, and then the pump to sequester the carbon below bedrock. Fill in the line and leave it to turn into oil once again in a few thousand years.
  • From Martin Wolterding on wt.social: (Paraphrased) Rather than genetically engineering algae, it may be possle to bring nutrient right water from great depths to the surface - with the nutrients causing algal growth that will remove CO2 from the atmosphere.
  • From Tony Nony on wt.social: We need to remove CO2 from the air as permanently as we can. So long as the algae remain alive, healthy and growing, then they're another form of plant life 'sequestering' carbon. One form (phytoplankton) does -half- of all photosynthesis on Earth. The WPedia articles says that 40% of them have gone missing since 1950 (possibly due to ocean warming). So to use algae as one carbon solution, you'd need to find out which species are hardiest. Some of them are among the fastest-growing renewable biomass sources (WP:see Algae#Energy_source), a resource that's expected to take off in the next decade.